GFZ – Science@Bleßberghöhle

First Reconstruction of the Holocene Climate

Posted on 6. May 20213. June 2021 by Norbert in Results

Breitenbach, Sebastian F. M.; Marwan, Norbert

Die Bleßberghöhle – ein Glücksfall für die Klimaforschung Book Section

In: Thüringer Höhlenverein, e. V. (Ed.): Nächster Halt: Bleßberghöhle, Suhl, 2022.

Breitenbach, Sebastian F. M.; Plessen, Birgit; Wenz, Sarah; Leonhardt, Jens; Tjallingii, Rik; Scholz, Denis; Jochum, Klaus-Peter; Marwan, Norbert

A multi-proxy reconstruction of Holocene climate change from Blessberg Cave, Germany Proceedings Article

In: Geophysical Research Abstracts, pp. EGU2016-14213, 2016.

Abstract | Links | BibTeX

@inproceedings{breitenbach2016,

title = {A multi-proxy reconstruction of Holocene climate change from Blessberg Cave, Germany},

author = {Sebastian F. M. Breitenbach and Birgit Plessen and Sarah Wenz and Jens Leonhardt and Rik Tjallingii and Denis Scholz and Klaus-Peter Jochum and Norbert Marwan},

url = {https://bbh.pik-potsdam.de/wp-content/uploads/2021/05/Breitenbach_poster_EGU_2016.pdf},

year  = {2016},

date = {2016-04-01},

booktitle = {Geophysical Research Abstracts},

volume = {18},

pages = {EGU2016-14213},

abstract = {Although Holocene climate dynamics were relatively stable compared to glacial conditions, climatic changes had significant impact on ecosystems and human society on various timescales (Mayewski et al. 2004, Donges et al. 2015, Tan et al. 2015). Precious few high-resolution records on Holocene temperature and precipitation conditions in Central Europe are available (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012).

Here we present a speleothem-based reconstruction of past climate dynamics from Blessberg Cave, Thuringia, central Germany. Three calcitic stalagmites were recovered when the cave was discovered during tunneling operations in 2008. Samples BB-1, -2 and -3 were precisely dated by the 230Th/U-method, with errors between 10 and 160 years (2σ). The combined record covers large parts of the Holocene (10 – 0.4 ka BP). δ13C and δ18O were analysed at 100 μm resolution. To gain additional insights in infiltration conditions, Sr/Ca and S/Ca were measured on BB-1 and BB-3 using an Röntgenanalytik Eagle XXL μXRF scanner.

Differences to other central European records (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012) suggest complex interaction between multiple factors influencing speleothem δ18O in Blessberg Cave. Furthermore, no clear influence of the North Atlantic Oscillation on our proxies is found. However, a link across the N Atlantic realm is indicated by a centennial-scale correlation between Blessberg δ18O values and minerogenic input into lake SS1220 in Greenland over the last 5 ka (Olsen et al. 2012). In addition, recurrence analysis indicates an imprint of Atlantic Bond events on Blessberg δ18O values (Marwan et al. 2014), corroborating the suggested link with high northern latitudes. Larger runoff into the Greenland lake seems to be associated with lower δ18O, higher δ13C and S/Ca ratios, as well as lower Sr/Ca ratios in Blessberg Cave speleothems. This might be linked to lower local temperature and/or changes in precipitation seasonality. Opposing millennial scale trends with lowering S/Ca ratios and δ13C values but increasing Sr/Ca ratios calls for more than one controlling factor. Most likely, δ13C decreased through the Holocene due to afforestation, which in turn might have increased sulphate retention in the thickening soil cover (Frisia et al. 2005) and limited sulphur flux into the cave. Alternatively, marine sulfur flux could have diminished with winter wind intensities. However, additional data is required to clarify this hypothesis. A positive Sr/Ca trend through the Holocene might result from increasing prior calcite precipitation induced by a negative moisture balance in summer.},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

Close

Although Holocene climate dynamics were relatively stable compared to glacial conditions, climatic changes had significant impact on ecosystems and human society on various timescales (Mayewski et al. 2004, Donges et al. 2015, Tan et al. 2015). Precious few high-resolution records on Holocene temperature and precipitation conditions in Central Europe are available (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012).
Here we present a speleothem-based reconstruction of past climate dynamics from Blessberg Cave, Thuringia, central Germany. Three calcitic stalagmites were recovered when the cave was discovered during tunneling operations in 2008. Samples BB-1, -2 and -3 were precisely dated by the 230Th/UU/Th-Datierung Die U/Th-Datierung ist eine sehr präzise radiometrische Altersbestimmung auf Basis der Uran-Thorium-Zerfallsreihe. Das Uran zerfällt mit bekannten Halbwertszeiten (245.500 Jahre) zum Tochterelement Thorium. Stalagmiten bauen bei ihrem Wachstum (fast) nur das wasserlösliche Uran ein, während das schlecht bewegliche Thorium zum größten Teil im Boden und Epikarst über der Höhle verbleibt. Das kann man nutzen, um die Zeit zu berechnen, die seit der Ausfällung der untersuchten Karbonatprobe vergangen ist. Moderne massenspektrometrische Verfahren erlauben Altersbestimmungen mit der U/Th-Methode bis zu 700.000 Jahren vor Heute.-method, with errors between 10 and 160 years (2σ). The combined record covers large parts of the Holocene (10 – 0.4 ka BPka BP Mit "ka BP" sind "Tausend Jahre vor 1950" gemeint. Das "BP" steht für "before present", was in der Paläoklima-Wissenschaft als 1950 festgelegt wurde. "11.000 ka BP" bedeuted also 11 Tausend Jahre vor 1950, oder unter Verwendung unseres gewohnten Kalenders: 9050 v. Chr.). δ13C and δ18O were analysed at 100 μm resolution. To gain additional insights in infiltration conditions, Sr/Ca and S/Ca were measured on BB-1 and BB-3 using an Röntgenanalytik Eagle XXL μXRF scanner.
Differences to other central European records (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012) suggest complex interaction between multiple factors influencing speleothem δ18O in Blessberg Cave. Furthermore, no clear influence of the North Atlantic Oscillation on our proxiesProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. is found. However, a link across the N Atlantic realm is indicated by a centennial-scale correlation between Blessberg δ18O values and minerogenic input into lake SS1220 in Greenland over the last 5 kaka BP Mit "ka BP" sind "Tausend Jahre vor 1950" gemeint. Das "BP" steht für "before present", was in der Paläoklima-Wissenschaft als 1950 festgelegt wurde. "11.000 ka BP" bedeuted also 11 Tausend Jahre vor 1950, oder unter Verwendung unseres gewohnten Kalenders: 9050 v. Chr. (Olsen et al. 2012). In addition, recurrence analysis indicates an imprint of Atlantic Bond events on Blessberg δ18O values (Marwan et al. 2014), corroborating the suggested link with high northern latitudes. Larger runoff into the Greenland lake seems to be associated with lower δ18O, higher δ13C and S/Ca ratios, as well as lower Sr/Ca ratios in Blessberg Cave speleothems. This might be linked to lower local temperature and/or changes in precipitation seasonality. Opposing millennial scale trends with lowering S/Ca ratios and δ13C values but increasing Sr/Ca ratios calls for more than one controlling factor. Most likely, δ13C decreased through the Holocene due to afforestation, which in turn might have increased sulphate retention in the thickening soil cover (Frisia et al. 2005) and limited sulphur flux into the cave. Alternatively, marine sulfur flux could have diminished with winter wind intensities. However, additional data is required to clarify this hypothesis. A positive Sr/Ca trend through the Holocene might result from increasing prior calcite precipitation induced by a negative moisture balance in summer.

Close

The first results of the geochemical analyses of the three stalagmites BB-1 to BB-3 already allow conclusions about the climatic changes of the last 14,000 years. A detailed interpretation can be found in the article Climate zone shift in Central Europe.

First results of analyses of BB-1 to BB-3

Mass spectrometer Northumbria University

Palaeoclimate of the Holocene

Posted on 28. April 202121. May 2021 by Norbert in Project

Project Lead

Northumbria University Newcastle, Geography and Environmental Sciences – Cold and Palaeo Environments Group

Involved Partners

Content

The first three stalagmites from the Bleßberg Cave (BB-1, BB-2, BB-3) grew during the last 10,000 years or so, the Holocene. By analysing stable isotopes and trace elements, various aspects of the past environmental and climatic conditions will be reconstructed. Although there are already first interesting published results, the investigation of these samples continues.

Results

Monitoring

Posted on 27. April 202127. April 2021 by Norbert in Project

Project Lead

Northumbria University Newcastle, Geography and Environmental Sciences – Cold and Palaeo Environments Group

Involved Partners

Content

For the quantitative reconstruction of past moisture regimes, detailed measurements of the environmental conditions in the cave, in the ground, and on the surface are carried out. This programme is led by Northumbria Uni and gets support from all sides, especially from the cavers on site. In the cave, water samples are mainly collected for stable isotopeIsotop Chemische Elemente können aus verschieden aufgebauten Atomen gebildet sein. Die Anzahl Protonen im Atomkern ist zwar dabei gleich, aber die Anzahl der Neutronen kann variieren. Man spricht dann von Isotopen, deren Massen kleine, aber messbare Unterschiede aufweisen. Der Atomkern des Sauerstoffs besteht z. B. aus 8 Protonen und in der Regel aus 8 Neutronen. Es gibt aber auch Sauerstoff, dessen Kerne aus 8 Protonen und 9 oder 10 Neutronen bestehen (neben selteneren, instabilen Sauerstoffisotopen). Um das zu kennzeichnen, gibt man zusätzlich zum chemischen Symbol noch die Massenzahl (Summe aus Protonen und Neutronen) an, also 16O, 17O oder 18O. Die unterschiedlichen Isotope verhalten sich zwar chemisch identisch, physikalisch aber - aufgrund ihres unterschiedlichen Gewichtes - leicht unterschiedlich. Damit stellen sie äusserst wertvolle Marker dar, die uns wichtige Hinweise zur Änderung des Klimas, der Umgebungsvegetation, Bodenaktivität und vielem mehr geben. analysis (δD and δ18O) and a number of parameters are measured, such as air and water temperature in the cave, water pressure, pCO2 and drip rates. At the surface, air temperature and soil temperatures are measured at different depths. In addition, carbonate is collected on watch glasses in the cave to support calibration studies and to better understand the growth dynamics of the stalagmites.

Dating and permafrost in Central Europe

Posted on 27. April 202127. April 2021 by Norbert in Project

Project Lead

Northumbria University Newcastle, Geography and Environmental Sciences – Cold and Palaeo Environments Group

Involved Partners

Content

How are U/ThU/Th-Datierung Die U/Th-Datierung ist eine sehr präzise radiometrische Altersbestimmung auf Basis der Uran-Thorium-Zerfallsreihe. Das Uran zerfällt mit bekannten Halbwertszeiten (245.500 Jahre) zum Tochterelement Thorium. Stalagmiten bauen bei ihrem Wachstum (fast) nur das wasserlösliche Uran ein, während das schlecht bewegliche Thorium zum größten Teil im Boden und Epikarst über der Höhle verbleibt. Das kann man nutzen, um die Zeit zu berechnen, die seit der Ausfällung der untersuchten Karbonatprobe vergangen ist. Moderne massenspektrometrische Verfahren erlauben Altersbestimmungen mit der U/Th-Methode bis zu 700.000 Jahren vor Heute. dating of cave carbonates in Europe distributed over time and space? Can these be used to spatiotemporally constrain permafrostPermafrost Unter Permafrost versteht man dauerhaft gefrorenen Boden, der auch im Sommer nicht auftaut. In Mitteleuropa gab es während den Eiszeiten Permafrost. in Europe?

Geoforschungszentrum Potsdam (GFZ) – Group stable isotopes (sediments and water)

Posted on 27. April 202124. March 2023 by Norbert in Group

The Geoforschungszentrum Potsdam is a non-university research institute that conducts research on the dynamics of the solid earth. It was founded in 1992 and is a member of the Helmholtz Association of German Research Centres.

The GFZ participates in research in the Bleßberg Cave through geochemical analyses of drip water and stalagmites.

Contact

Dr. Birgit Schröder

Web site

https://www.gfz-potsdam.de/

Publications

Klose, J.; Scholz, D.; Weber, M.; Vonhof, H.; Plessen, B.; Breitenbach, S.; Marwan, N.

Timing of Dansgaard-Oeschger events in Central Europe based on three precisely dated speleothems from Bleßberg Cave, Germany Proceedings

Poster, 2023, (Summer School on Speleothem Sciences 2023, Sao Paulo).

Abstract | Links | BibTeX

@proceedings{klose2023poster,

title = {Timing of Dansgaard-Oeschger events in Central Europe based on three precisely dated speleothems from Bleßberg Cave, Germany},

author = {J. Klose and D. Scholz and M. Weber and H. Vonhof and B. Plessen and S. Breitenbach and N. Marwan},

editor = {Summer School on Speleothem Sciences 2023, Sao Paulo},

url = {https://bbh.pik-potsdam.de/wp-content/uploads/2024/09/klose_SummerschoolSaoPaulo2023.pdf},

year  = {2023},

date = {2023-08-07},

urldate = {2023-08-07},

abstract = {The last glacial period and especially Marine Isotope stage 3 (MIS 3, ca. 57 - 27 ka) was characterized by various climate oscillations (i.e., rapid increases in temperature, followed by a gradual cooling, the Dansgaard-Oeschger (D/O) events), which were first discovered in Greenland ice cores. Although their causes are still not fully understood, clear evidence for their supra-regional character was found in various climate records around the globe. However, European speleothem samples, which grew during MIS 3, are limited and mainly restricted to alpine regions, where glacier meltwater enabled speleothem growth, and to south/south-western parts of Europe characterised by a generally warmer climate. This led to the opinion that it was too cold and/or too dry in central Europe for speleothem growth. Here we present three speleothem (flowstone) records from Bleßberg Cave, Germany, which grew during MIS 3. 

All flowstones show episodical growth patterns with distinctive, thin growth phases. Potential contamination deriving form detrital material deposited during hiatuses between individual growth phases, open-system behaviour around the hiatuses and the limited thickness of the growth layers are the biggest challenges during sampling for 230Th/U dating. By combination of different sampling techniques (i.e., laser ablation and micro-milling) in addition to the common approach of handheld drilling and due to the relatively high 238U concentration of the samples (approx. 0.4 – 1 µg/g), we were able to date even the thinnest growth layers (< 2 mm) of the Bleßberg flowstones with a very high precision (i.e., with 2σ-age uncertainties of a few hundred years or even lower).

The timing of the growth phases of the Bleßberg flowstones correlates with several D/O events recorded in the Greenland ice cores. This proves that at least some phases of MIS 3 had favourable climate conditions for speleothem growth in Central Europe. In addition, the analysis of the stable oxygen and carbon isotopes (δ18O and δ13C) for all three flowstones revealed several D/O events, which have not been recorded in any other speleothem from central Europe so far. This will enhance our understanding of climate variability during MIS 3 and specific D/O events in central Europe.},

howpublished = {Poster},

note = {Summer School on Speleothem Sciences 2023, Sao Paulo},

keywords = {},

pubstate = {published},

tppubtype = {proceedings}

}

Close

The last glacial period and especially Marine IsotopeIsotop Chemische Elemente können aus verschieden aufgebauten Atomen gebildet sein. Die Anzahl Protonen im Atomkern ist zwar dabei gleich, aber die Anzahl der Neutronen kann variieren. Man spricht dann von Isotopen, deren Massen kleine, aber messbare Unterschiede aufweisen. Der Atomkern des Sauerstoffs besteht z. B. aus 8 Protonen und in der Regel aus 8 Neutronen. Es gibt aber auch Sauerstoff, dessen Kerne aus 8 Protonen und 9 oder 10 Neutronen bestehen (neben selteneren, instabilen Sauerstoffisotopen). Um das zu kennzeichnen, gibt man zusätzlich zum chemischen Symbol noch die Massenzahl (Summe aus Protonen und Neutronen) an, also 16O, 17O oder 18O. Die unterschiedlichen Isotope verhalten sich zwar chemisch identisch, physikalisch aber - aufgrund ihres unterschiedlichen Gewichtes - leicht unterschiedlich. Damit stellen sie äusserst wertvolle Marker dar, die uns wichtige Hinweise zur Änderung des Klimas, der Umgebungsvegetation, Bodenaktivität und vielem mehr geben. stage 3 (MIS 3MIS 3 "MIS" ist die Abkürzung für "marine isotope stage", übersetzt also "Isotopenstadium mariner Sedimente". Da sich beim Wechsel von Warm- zu Kaltzeiten (und umgekehrt) die Isotopenverhältnisse in den Kalkschalen kleiner Einzeller (Foraminiferen) auf dem Meeresboden ändern, werden diese zur Datierung herangezogen und lassen sich zur Eingruppierung verschiedener Klimazustände in der Vergangenheit nutzen. "MIS 3" bedeutet dabei eine kurzzeitige Warmphase (beginnend vor 57 Tausend Jahren) während der letzten Eiszeit., ca. 57 - 27 kaka BP Mit "ka BP" sind "Tausend Jahre vor 1950" gemeint. Das "BP" steht für "before present", was in der Paläoklima-Wissenschaft als 1950 festgelegt wurde. "11.000 ka BP" bedeuted also 11 Tausend Jahre vor 1950, oder unter Verwendung unseres gewohnten Kalenders: 9050 v. Chr.) was characterized by various climate oscillations (i.e., rapid increases in temperature, followed by a gradual cooling, the Dansgaard-Oeschger (D/O) events), which were first discovered in Greenland ice cores. Although their causes are still not fully understood, clear evidence for their supra-regional character was found in various climate records around the globe. However, European speleothem samples, which grew during MIS 3, are limited and mainly restricted to alpine regions, where glacier meltwater enabled speleothem growth, and to south/south-western parts of Europe characterised by a generally warmer climate. This led to the opinion that it was too cold and/or too dry in central Europe for speleothem growth. Here we present three speleothem (flowstone) records from Bleßberg Cave, Germany, which grew during MIS 3.
All flowstones show episodical growth patterns with distinctive, thin growth phases. Potential contamination deriving form detrital material deposited during hiatuses between individual growth phases, open-system behaviour around the hiatuses and the limited thickness of the growth layers are the biggest challenges during sampling for 230Th/UU/Th-Datierung Die U/Th-Datierung ist eine sehr präzise radiometrische Altersbestimmung auf Basis der Uran-Thorium-Zerfallsreihe. Das Uran zerfällt mit bekannten Halbwertszeiten (245.500 Jahre) zum Tochterelement Thorium. Stalagmiten bauen bei ihrem Wachstum (fast) nur das wasserlösliche Uran ein, während das schlecht bewegliche Thorium zum größten Teil im Boden und Epikarst über der Höhle verbleibt. Das kann man nutzen, um die Zeit zu berechnen, die seit der Ausfällung der untersuchten Karbonatprobe vergangen ist. Moderne massenspektrometrische Verfahren erlauben Altersbestimmungen mit der U/Th-Methode bis zu 700.000 Jahren vor Heute. dating. By combination of different sampling techniques (i.e., laser ablation and micro-milling) in addition to the common approach of handheld drilling and due to the relatively high 238U concentration of the samples (approx. 0.4 – 1 µg/g), we were able to date even the thinnest growth layers (< 2 mm) of the Bleßberg flowstones with a very high precision (i.e., with 2σ-age uncertainties of a few hundred years or even lower).
The timing of the growth phases of the Bleßberg flowstones correlates with several D/O events recorded in the Greenland ice cores. This proves that at least some phases of MIS 3 had favourable climate conditions for speleothem growth in Central Europe. In addition, the analysis of the stable oxygen and carbon isotopes (δ18O and δ13C) for all three flowstones revealed several D/O events, which have not been recorded in any other speleothem from central Europe so far. This will enhance our understanding of climate variability during MIS 3 and specific D/O events in central Europe.

Close

Klose, J.; Weber, M.; Vonhof, H.; Plessen, B.; Breitenbach, S.; Marwan, N.; Scholz, D.

Timing of Dansgaard-Oeschger events in Central Europe based on three precisely dated speleothems from Bleßberg Cave, Germany Proceedings

Poster, 2022, (KR9 Konferenz in Innsbruck).

Abstract | Links | BibTeX

@proceedings{klose2022,

title = {Timing of Dansgaard-Oeschger events in Central Europe based on three precisely dated speleothems from Bleßberg Cave, Germany},

author = {J. Klose and M. Weber and H. Vonhof and B. Plessen and S. Breitenbach and N. Marwan and D. Scholz},

editor = {KR9 in Innsbruck, 2022},

url = {https://bbh.pik-potsdam.de/wp-content/uploads/2024/09/klose_KR9-Innsbruck2022.pdf},

year  = {2022},

date = {2022-07-19},

urldate = {2022-07-19},

abstract = {The last glacial period and especially Marine Isotope stage 3 (MIS 3, ca. 57 - 27 ka) was characterized by various climate oscillations (i.e., rapid increases in temperature, followed by a gradual cooling, the Dansgaard-Oeschger (D/O) events), which were first discovered in Greenland ice cores. Although their causes are still not fully understood, clear evidence for their supra-regional character was found in various climate records around the globe. However, European speleothem samples, which grew during MIS 3, are limited and mainly restricted to alpine regions, where glacier meltwater enabled speleothem growth, and to south/south-western parts of Europe characterised by a generally warmer climate. This led to the opinion that it was too cold and/or too dry in central Europe for speleothem growth. Here we present three speleothem (flowstone) records from Bleßberg Cave, Germany, which grew during MIS 3. 

All flowstones show episodical growth patterns with distinctive, thin growth phases. Potential contamination deriving form detrital material deposited during hiatuses between individual growth phases, open-system behaviour around the hiatuses and the limited thickness of the growth layers are the biggest challenges during sampling for 230Th/U dating. By combination of different sampling techniques (i.e., laser ablation and micro-milling) in addition to the common approach of handheld drilling and due to the relatively high 238U concentration of the samples (approx. 0.4 – 1 µg/g), we were able to date even the thinnest growth layers (< 2 mm) of the Bleßberg flowstones with a very high precision (i.e., with 2σ-age uncertainties of a few hundred years or even lower).

The timing of the growth phases of the Bleßberg flowstones correlates with several D/O events recorded in the Greenland ice cores. This proves that at least some phases of MIS 3 had favourable climate conditions for speleothem growth in Central Europe. In addition, the analysis of the stable oxygen and carbon isotopes (δ18O and δ13C) for all three flowstones revealed several D/O events, which have not been recorded in any other speleothem from central Europe so far. This will enhance our understanding of climate variability during MIS 3 and specific D/O events in central Europe.},

howpublished = {Poster},

note = {KR9 Konferenz in Innsbruck},

keywords = {},

pubstate = {published},

tppubtype = {proceedings}

}

Close

The last glacial period and especially Marine Isotope stage 3 (MIS 3, ca. 57 - 27 ka) was characterized by various climate oscillations (i.e., rapid increases in temperature, followed by a gradual cooling, the Dansgaard-Oeschger (D/O) events), which were first discovered in Greenland ice cores. Although their causes are still not fully understood, clear evidence for their supra-regional character was found in various climate records around the globe. However, European speleothem samples, which grew during MIS 3, are limited and mainly restricted to alpine regions, where glacier meltwater enabled speleothem growth, and to south/south-western parts of Europe characterised by a generally warmer climate. This led to the opinion that it was too cold and/or too dry in central Europe for speleothem growth. Here we present three speleothem (flowstone) records from Bleßberg Cave, Germany, which grew during MIS 3.
All flowstones show episodical growth patterns with distinctive, thin growth phases. Potential contamination deriving form detrital material deposited during hiatuses between individual growth phases, open-system behaviour around the hiatuses and the limited thickness of the growth layers are the biggest challenges during sampling for 230Th/U dating. By combination of different sampling techniques (i.e., laser ablation and micro-milling) in addition to the common approach of handheld drilling and due to the relatively high 238U concentration of the samples (approx. 0.4 – 1 µg/g), we were able to date even the thinnest growth layers (< 2 mm) of the Bleßberg flowstones with a very high precision (i.e., with 2σ-age uncertainties of a few hundred years or even lower).
The timing of the growth phases of the Bleßberg flowstones correlates with several D/O events recorded in the Greenland ice cores. This proves that at least some phases of MIS 3 had favourable climate conditions for speleothem growth in Central Europe. In addition, the analysis of the stable oxygen and carbon isotopes (δ18O and δ13C) for all three flowstones revealed several D/O events, which have not been recorded in any other speleothem from central Europe so far. This will enhance our understanding of climate variability during MIS 3 and specific D/O events in central Europe.

Close

Klose, Jennifer; Scholz, Denis; Breitenbach, Sebastian F. M.; Plessen, Birgit; Vonhof, Hubert

Determination of phases of warm climate during MIS 3 in Central Europe based on precisely dated speleothems from Bleßberg Cave, Germany Proceedings

Poster, 2021, (GeoKarlsruhe 2021: Sustainable Earth – From processes to resources, Karlsruhe).

Abstract | BibTeX

@proceedings{klose2021,

title = {Determination of phases of warm climate during MIS 3 in Central Europe based on precisely dated speleothems from Bleßberg Cave, Germany},

author = {Jennifer Klose and Denis Scholz and Sebastian F. M. Breitenbach and Birgit Plessen and Hubert Vonhof},

editor = {GeoKarlsruhe 2021: Sustainable Earth – From processes to resources},

year  = {2021},

date = {2021-09-22},

urldate = {2021-09-22},

abstract = {Speleothems provide a great opportunity for paleoclimate reconstruction because they occur almost worldwide and can be dated very precisely using the U-series disequilibrium method. The most commonly used climate proxies are stable isotope values (δ18O and δ13C) and trace elements. However, these are influenced by a variety of surface and in-cave processes, which results in a non-trivial interpretation of the speleothem proxy signals.



The last glacial period and in particular the Marine Isotope Stage (MIS) 3 is, compared to the recent warm phase, the Holocene, characterised by larger climate oscillations. These are detectable in δ18O records from Greenland ice cores and also climate archives in Europe, such as pollen or tree ring records. Unfortunately, little direct proxy evidence is available from central Europe, and the climatic and environmental conditions during MIS 3 remain largely enigmatic. Speleothem records from central Europe during MIS 3 are limited due to cold climate conditions and mainly restricted to the warmer southern or alpine regions.



Here we present the first results of two flowstones from Bleßberg Cave in Germany. Preliminary 230Th/U-ages make these flowstones the most northern continental growth of speleothems during MIS 3 in central Europe. Thus, these samples provide the unique opportunity to reconstruct climate variability during parts of the last glacial period. With the combination of several different proxies, such as stable isotopes, trace elements and the results from cave monitoring, we will be able to obtain detailed insights into environmental conditions in central Europe during MIS 3 and the Late Glacial.},

howpublished = {Poster},

note = {GeoKarlsruhe 2021: Sustainable Earth – From processes to resources, Karlsruhe},

keywords = {},

pubstate = {published},

tppubtype = {proceedings}

}

Close

Speleothems provide a great opportunity for paleoclimate reconstruction because they occur almost worldwide and can be dated very precisely using the U-series disequilibrium method. The most commonly used climate proxiesProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. are stable isotope values (δ18O and δ13C) and trace elements. However, these are influenced by a variety of surface and in-cave processes, which results in a non-trivial interpretation of the speleothem proxyProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. signals.

The last glacial period and in particular the Marine Isotope Stage (MISMIS "MIS" ist die Abkürzung für "marine isotope stage", übersetzt also "Isotopenstadium mariner Sedimente". Da sich beim Wechsel von Warm- zu Kaltzeiten (und umgekehrt) die Isotopenverhältnisse in den Kalkschalen kleiner Einzeller (Foraminiferen) auf dem Meeresboden ändern, werden diese zur Datierung herangezogen und lassen sich zur Eingruppierung verschiedener Klimazustände in der Vergangenheit nutzen. Die MIS werden rückwärts nummeriert (also größere Zahl = älter) und ungerade Zahlen stehen für Warmzeiten, gerade für Kaltzeiten.) 3 is, compared to the recent warm phase, the Holocene, characterised by larger climate oscillations. These are detectable in δ18O records from Greenland ice cores and also climate archives in Europe, such as pollen or tree ring records. Unfortunately, little direct proxy evidence is available from central Europe, and the climatic and environmental conditions during MIS 3 remain largely enigmatic. Speleothem records from central Europe during MIS 3 are limited due to cold climate conditions and mainly restricted to the warmer southern or alpine regions.

Here we present the first results of two flowstones from Bleßberg Cave in Germany. Preliminary 230Th/U-ages make these flowstones the most northern continental growth of speleothems during MIS 3 in central Europe. Thus, these samples provide the unique opportunity to reconstruct climate variability during parts of the last glacial period. With the combination of several different proxies, such as stable isotopes, trace elements and the results from cave monitoring, we will be able to obtain detailed insights into environmental conditions in central Europe during MIS 3 and the Late Glacial.

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Breitenbach, Sebastian F. M.; Plessen, Birgit; Waltgenbach, Sarah; Tjallingii, Rik; Leonhardt, Jens; Jochum, Klaus-Peter; Meyer, Hanno; Goswami, Bedartha; Marwan, Norbert; Scholz, Denis

Holocene interaction of maritime and continental climate in Central Europe: New speleothem evidence from Central Germany Journal Article

In: Global and Planetary Change, vol. 176, pp. 144–161, 2019.

Abstract | Links | BibTeX

@article{breitenbach2019,

title = {Holocene interaction of maritime and continental climate in Central Europe: New speleothem evidence from Central Germany},

author = {Sebastian F. M. Breitenbach and Birgit Plessen and Sarah Waltgenbach and Rik Tjallingii and Jens Leonhardt and Klaus-Peter Jochum and Hanno Meyer and Bedartha Goswami and Norbert Marwan and Denis Scholz},

doi = {10.1016/j.gloplacha.2019.03.007},

year  = {2019},

date = {2019-00-00},

journal = {Global and Planetary Change},

volume = {176},

pages = {144–161},

abstract = {Central European climate is strongly influenced by North Atlantic (Westerlies) and Siberian High circulation patterns, which govern precipitation and temperature dynamics and induce heterogeneous climatic conditions, with distinct boundaries between climate zones. These climate boundaries are not stationary and shift geographically, depending on long-term atmospheric conditions. So far, little is known about past shifts of these climate boundaries and the local to regional environmental response prior to the instrumental era.



High resolution multi-proxy data (stable oxygen and carbon isotope ratios, S/Ca and Sr/Ca) from two Holocene stalagmites from Bleßberg Cave (Thuringia) are used here to differentiate local and pan-regional environmental and climatic conditions Central Germany through the Holocene. Carbon isotope and S/Ca and Sr/Ca ratios inform us on local Holocene environmental changes in and around the cave, while δ18O (when combined with independent records) serves as proxy for (pan-)regional atmospheric conditions.



The stable carbon isotope record suggests repeated changes in vegetation density (open vs. dense forest), and increasing forest cover in the late Holocene. Concurrently, decreasing S/Ca values indicate more effective sulfur retention in better developed soils, with a stabilization in the mid-Holocene. This goes in hand with changes in effective summer infiltration, reflected in the Sr/Ca profile. Highest Sr/Ca values between 4 ka and 1 ka BP indicate intensified prior calcite precipitation resulting from reduced effective moisture supply.



The region of Bleßberg Cave is sensitive to shifts of the boundary between maritime (Cfb) and continental (Dfb) climate and ideally suited to reconstruct past meridional shifts of this divide. We combined the Bleßberg Cave δ18O time series with δ18O data from Bunker Cave (western Germany) and a North Atlantic Oscillation (NAO) record from lake SS1220 (SW Greenland) to reconstruct the mean position of the Cfb-Dfb climate boundary. We further estimate the dynamic interplay of the North Atlantic Oscillation and the Siberian High and their influence on Central European climate. Repeated shifts of the Cfb-Dfb boundary over the last 4000 years might explain previously observed discrepancies between proxy records from Europe. Detailed correlation analyses reveal multi-centennial scale alternations of maritime and continental climate and, concurrently, waning and waxing influences of Siberian High and NAO on Central Europe.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

Close

Central European climate is strongly influenced by North Atlantic (Westerlies) and Siberian High circulation patterns, which govern precipitation and temperature dynamics and induce heterogeneous climatic conditions, with distinct boundaries between climate zones. These climate boundaries are not stationary and shift geographically, depending on long-term atmospheric conditions. So far, little is known about past shifts of these climate boundaries and the local to regional environmental response prior to the instrumental era.

High resolution multi-proxyProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. data (stable oxygen and carbon isotope ratios, S/Ca and Sr/Ca) from two Holocene stalagmites from Bleßberg Cave (Thuringia) are used here to differentiate local and pan-regional environmental and climatic conditions Central Germany through the Holocene. Carbon isotope and S/Ca and Sr/Ca ratios inform us on local Holocene environmental changes in and around the cave, while δ18O (when combined with independent records) serves as proxy for (pan-)regional atmospheric conditions.

The stable carbon isotope record suggests repeated changes in vegetation density (open vs. dense forest), and increasing forest cover in the late Holocene. Concurrently, decreasing S/Ca values indicate more effective sulfur retention in better developed soils, with a stabilization in the mid-Holocene. This goes in hand with changes in effective summer infiltration, reflected in the Sr/Ca profile. Highest Sr/Ca values between 4 ka and 1 ka BPka BP Mit "ka BP" sind "Tausend Jahre vor 1950" gemeint. Das "BP" steht für "before present", was in der Paläoklima-Wissenschaft als 1950 festgelegt wurde. "11.000 ka BP" bedeuted also 11 Tausend Jahre vor 1950, oder unter Verwendung unseres gewohnten Kalenders: 9050 v. Chr. indicate intensified prior calcite precipitation resulting from reduced effective moisture supply.

The region of Bleßberg Cave is sensitive to shifts of the boundary between maritime (Cfb) and continental (Dfb) climate and ideally suited to reconstruct past meridional shifts of this divide. We combined the Bleßberg Cave δ18O time series with δ18O data from Bunker Cave (western Germany) and a North Atlantic Oscillation (NAO) record from lake SS1220 (SW Greenland) to reconstruct the mean position of the Cfb-Dfb climate boundary. We further estimate the dynamic interplay of the North Atlantic Oscillation and the Siberian High and their influence on Central European climate. Repeated shifts of the Cfb-Dfb boundary over the last 4000 years might explain previously observed discrepancies between proxy records from Europe. Detailed correlation analyses reveal multi-centennial scale alternations of maritime and continental climate and, concurrently, waning and waxing influences of Siberian High and NAO on Central Europe.

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Breitenbach, Sebastian F. M.; Plessen, Birgit; Waltgenbach, Sarah; Tjallingii, Rik; Leonhardt, Jens; Jochum, Klaus-Peter; Meyer, Hanno; Marwan, Norbert; Scholz, Denis

Tracing past shifts of the boundary between maritime and continental climate over Central Europe Proceedings Article

In: Geophysical Research Abstracts, pp. EGU2018-9046, 2018.

Abstract | Links | BibTeX

@inproceedings{breitenbach2018,

title = {Tracing past shifts of the boundary between maritime and continental climate over Central Europe},

author = {Sebastian F. M. Breitenbach and Birgit Plessen and Sarah Waltgenbach and Rik Tjallingii and Jens Leonhardt and Klaus-Peter Jochum and Hanno Meyer and Norbert Marwan and Denis Scholz},

url = {https://bbh.pik-potsdam.de/wp-content/uploads/2021/04/EGU2018-9046.pdf},

year  = {2018},

date = {2018-04-01},

booktitle = {Geophysical Research Abstracts},

volume = {20},

pages = {EGU2018-9046},

abstract = { European climate is characterized by heterogeneous climate conditions, with distinct boundaries between zones that can be classified according to the Köppen classification (Peel et al. 2007), and detected using climate network techniques (Rheinwalt et al. 2016). These boundaries are not stationary, but shift geographically, depending on large scale atmospheric conditions. Central European climate is strongly influenced by intricately linked North Atlantic Oscillation and Siberian High (SH), which govern precipitation and temperature over Europe. Shifts of these climatic boundaries in response to global warming and circulation changes might lead to more frequent extreme weather patterns like heat waves, with significant repercussions for society (Cohen et al. 2014). Speleothem-based palaeoclimate reconstructions enable us to understand underlying forcing mechanisms and speed of climatic reorganizations. Here we present a first reconstruction of multi-centennial shifts of the boundary between western European maritime Cfb climate and continental Dfb climate through the last ca. 5,000 years using speleothems from Bleßberg Cave, Thuringia, Central Europe. Thanks to its location near the Cfb-Dfb climatic boundary, Bleßberg Cave is ideally suited to reconstruct past W-E shifts of this divide longitudinally crossing Central Europe. We compare a decadally resolved stalagmite δ18O record with data from Bunker Cave (Mischel et al. 2017), western Germany, and an NAO reconstruction from Greenland (Olsen et al. 2012). Over the last 5,000 years, the boundary between Cfb and Dfb climate shifted repeatedly. When the Cfb-Dfb border was east (west) of Bleßberg (Bunker) Cave maritime (continental) climate prevailed at both sites. Discrepancies between investigated proxy records are found when the boundary is located between the two caves. Comparison with the Greenland NAO record shows that a westerly shifted boundary is often associated with a strong SH and a negative NAO. An easterly shift, in contrast, is found to be linked with weak a SH and a positive NAO.},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

Close

European climate is characterized by heterogeneous climate conditions, with distinct boundaries between zones that can be classified according to the Köppen classification (Peel et al. 2007), and detected using climate network techniques (Rheinwalt et al. 2016). These boundaries are not stationary, but shift geographically, depending on large scale atmospheric conditions. Central European climate is strongly influenced by intricately linked North Atlantic Oscillation and Siberian High (SH), which govern precipitation and temperature over Europe. Shifts of these climatic boundaries in response to global warming and circulation changes might lead to more frequent extreme weather patterns like heat waves, with significant repercussions for society (Cohen et al. 2014). Speleothem-based palaeoclimate reconstructions enable us to understand underlying forcing mechanisms and speed of climatic reorganizations. Here we present a first reconstruction of multi-centennial shifts of the boundary between western European maritime Cfb climate and continental Dfb climate through the last ca. 5,000 years using speleothems from Bleßberg Cave, Thuringia, Central Europe. Thanks to its location near the Cfb-Dfb climatic boundary, Bleßberg Cave is ideally suited to reconstruct past W-E shifts of this divide longitudinally crossing Central Europe. We compare a decadally resolved stalagmite δ18O record with data from Bunker Cave (Mischel et al. 2017), western Germany, and an NAO reconstruction from Greenland (Olsen et al. 2012). Over the last 5,000 years, the boundary between Cfb and Dfb climate shifted repeatedly. When the Cfb-Dfb border was east (west) of Bleßberg (Bunker) Cave maritime (continental) climate prevailed at both sites. Discrepancies between investigated proxy records are found when the boundary is located between the two caves. Comparison with the Greenland NAO record shows that a westerly shifted boundary is often associated with a strong SH and a negative NAO. An easterly shift, in contrast, is found to be linked with weak a SH and a positive NAO.

Close

Breitenbach, Sebastian F. M.; Plessen, Birgit; Wenz, Sarah; Leonhardt, Jens; Tjallingii, Rik; Scholz, Denis; Jochum, Klaus-Peter; Marwan, Norbert

A multi-proxy reconstruction of Holocene climate change from Blessberg Cave, Germany Proceedings Article

In: Geophysical Research Abstracts, pp. EGU2016-14213, 2016.

Abstract | Links | BibTeX

@inproceedings{breitenbach2016,

title = {A multi-proxy reconstruction of Holocene climate change from Blessberg Cave, Germany},

author = {Sebastian F. M. Breitenbach and Birgit Plessen and Sarah Wenz and Jens Leonhardt and Rik Tjallingii and Denis Scholz and Klaus-Peter Jochum and Norbert Marwan},

url = {https://bbh.pik-potsdam.de/wp-content/uploads/2021/05/Breitenbach_poster_EGU_2016.pdf},

year  = {2016},

date = {2016-04-01},

booktitle = {Geophysical Research Abstracts},

volume = {18},

pages = {EGU2016-14213},

abstract = {Although Holocene climate dynamics were relatively stable compared to glacial conditions, climatic changes had significant impact on ecosystems and human society on various timescales (Mayewski et al. 2004, Donges et al. 2015, Tan et al. 2015). Precious few high-resolution records on Holocene temperature and precipitation conditions in Central Europe are available (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012).

Here we present a speleothem-based reconstruction of past climate dynamics from Blessberg Cave, Thuringia, central Germany. Three calcitic stalagmites were recovered when the cave was discovered during tunneling operations in 2008. Samples BB-1, -2 and -3 were precisely dated by the 230Th/U-method, with errors between 10 and 160 years (2σ). The combined record covers large parts of the Holocene (10 – 0.4 ka BP). δ13C and δ18O were analysed at 100 μm resolution. To gain additional insights in infiltration conditions, Sr/Ca and S/Ca were measured on BB-1 and BB-3 using an Röntgenanalytik Eagle XXL μXRF scanner.

Differences to other central European records (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012) suggest complex interaction between multiple factors influencing speleothem δ18O in Blessberg Cave. Furthermore, no clear influence of the North Atlantic Oscillation on our proxies is found. However, a link across the N Atlantic realm is indicated by a centennial-scale correlation between Blessberg δ18O values and minerogenic input into lake SS1220 in Greenland over the last 5 ka (Olsen et al. 2012). In addition, recurrence analysis indicates an imprint of Atlantic Bond events on Blessberg δ18O values (Marwan et al. 2014), corroborating the suggested link with high northern latitudes. Larger runoff into the Greenland lake seems to be associated with lower δ18O, higher δ13C and S/Ca ratios, as well as lower Sr/Ca ratios in Blessberg Cave speleothems. This might be linked to lower local temperature and/or changes in precipitation seasonality. Opposing millennial scale trends with lowering S/Ca ratios and δ13C values but increasing Sr/Ca ratios calls for more than one controlling factor. Most likely, δ13C decreased through the Holocene due to afforestation, which in turn might have increased sulphate retention in the thickening soil cover (Frisia et al. 2005) and limited sulphur flux into the cave. Alternatively, marine sulfur flux could have diminished with winter wind intensities. However, additional data is required to clarify this hypothesis. A positive Sr/Ca trend through the Holocene might result from increasing prior calcite precipitation induced by a negative moisture balance in summer.},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

Close

Although Holocene climate dynamics were relatively stable compared to glacial conditions, climatic changes had significant impact on ecosystems and human society on various timescales (Mayewski et al. 2004, Donges et al. 2015, Tan et al. 2015). Precious few high-resolution records on Holocene temperature and precipitation conditions in Central Europe are available (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012).
Here we present a speleothem-based reconstruction of past climate dynamics from Blessberg Cave, Thuringia, central Germany. Three calcitic stalagmites were recovered when the cave was discovered during tunneling operations in 2008. Samples BB-1, -2 and -3 were precisely dated by the 230Th/U-method, with errors between 10 and 160 years (2σ). The combined record covers large parts of the Holocene (10 – 0.4 ka BP). δ13C and δ18O were analysed at 100 μm resolution. To gain additional insights in infiltration conditions, Sr/Ca and S/Ca were measured on BB-1 and BB-3 using an Röntgenanalytik Eagle XXL μXRF scanner.
Differences to other central European records (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012) suggest complex interaction between multiple factors influencing speleothem δ18O in Blessberg Cave. Furthermore, no clear influence of the North Atlantic Oscillation on our proxies is found. However, a link across the N Atlantic realm is indicated by a centennial-scale correlation between Blessberg δ18O values and minerogenic input into lake SS1220 in Greenland over the last 5 ka (Olsen et al. 2012). In addition, recurrence analysis indicates an imprint of Atlantic Bond events on Blessberg δ18O values (Marwan et al. 2014), corroborating the suggested link with high northern latitudes. Larger runoff into the Greenland lake seems to be associated with lower δ18O, higher δ13C and S/Ca ratios, as well as lower Sr/Ca ratios in Blessberg Cave speleothems. This might be linked to lower local temperature and/or changes in precipitation seasonality. Opposing millennial scale trends with lowering S/Ca ratios and δ13C values but increasing Sr/Ca ratios calls for more than one controlling factor. Most likely, δ13C decreased through the Holocene due to afforestation, which in turn might have increased sulphate retention in the thickening soil cover (Frisia et al. 2005) and limited sulphur flux into the cave. Alternatively, marine sulfur flux could have diminished with winter wind intensities. However, additional data is required to clarify this hypothesis. A positive Sr/Ca trend through the Holocene might result from increasing prior calcite precipitation induced by a negative moisture balance in summer.

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Wenz, Sarah; Scholz, Denis; Spötl, Christoph; Plessen, Birgit; Mischel, Simon; Breitenbach, Sebastian F. M.; Jochum, Klaus-Peter; Fohlmeister, Jens

Timing and duration of climate variability during the 8.2 ka event reconstructed from four speleothems from Germany Proceedings Article

In: Geophysical Research Abstracts, pp. EGU2016-12731, 2016.

Abstract | Links | BibTeX

@inproceedings{wenz2016,

title = {Timing and duration of climate variability during the 8.2 ka event reconstructed from four speleothems from Germany},

author = {Sarah Wenz and Denis Scholz and Christoph Spötl and Birgit Plessen and Simon Mischel and Sebastian F. M. Breitenbach and Klaus-Peter Jochum and Jens Fohlmeister },

url = {https://bbh.pik-potsdam.de/wp-content/uploads/2021/04/EGU2016-12731.pdf},

year  = {2016},

date = {2016-04-01},

booktitle = {Geophysical Research Abstracts},

volume = {18},

pages = {EGU2016-12731},

abstract = {The most prominent climate anomaly of the Holocene is the 8.2 ka event, which reflects the impact of a dramatic freshwater influx into the North Atlantic during an interglacial climate state. Thus, it can be considered as a possible analogue for future climate change. Due to the short-lived nature of the event (160.5 ± 5.5 years; Thomas et al., 2007), a detailed investigation requires archives of both high temporal resolution and accurate chronology.

We present high-resolution stable oxygen and carbon isotope (ca. 3-4 years) as well as sub-annually resolved trace element records of the 8.2 ka event from stalagmites (BB-3, Bu4, HLK2 and TV1) from three cave systems in Germany (Blessberg Cave, Bunker Cave and Herbstlabyrinth). The location of these caves in central European is well suited in order to detect changes in temperature and precipitation in relation to changes in the North Atlantic region (Fohlmeister et al., 2012). The 8.2 ka event is clearly recorded as a pronounced negative excursion in the δ18O values of all four speleothems. While stalagmites BB-3 from Blessberg Cave and Bu4 from Bunker Cave also show a negative excursion in the δ13C values during the event, the two speleothems from Herbstlabyrinth show no distinctive features in their δ13C values. The timing, duration and structure of the event differ between the individual records. In BB-3, the event occurs earlier (ca. 8.4 ka) and has a relatively short duration of ca. 90 years. In Bu4, the event occurs later (ca. 8.1 ka) and shows a relatively long duration of more than 200 years. In the two speleothems from the Herbstlabyrinth, the event is replicated and has a timing between 8.3 and 8.1 ka and a duration of ca. 150 years. These differences may at least in part be related to the dating uncertainties of 100-200 years (95 % confidence limits).

},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

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Marwan, Norbert; Breitenbach, Sebastian F. M.; Plessen, Birgit; Scholz, Denis; Leonhardt, Jens

Recurrence properties as signatures for abrupt climate change Proceedings Article

In: Geophysical Research Abstracts, pp. EGU2014-8893, 2014.

Abstract | Links | BibTeX

Quantitative climate reconstruction for Marine Isotope Stage 3

Posted on 15. April 202128. April 2021 by Norbert in Project

DFG Project: Quantitative climate reconstruction for MIS 3MIS 3 "MIS" ist die Abkürzung für "marine isotope stage", übersetzt also "Isotopenstadium mariner Sedimente". Da sich beim Wechsel von Warm- zu Kaltzeiten (und umgekehrt) die Isotopenverhältnisse in den Kalkschalen kleiner Einzeller (Foraminiferen) auf dem Meeresboden ändern, werden diese zur Datierung herangezogen und lassen sich zur Eingruppierung verschiedener Klimazustände in der Vergangenheit nutzen. "MIS 3" bedeutet dabei eine kurzzeitige Warmphase (beginnend vor 57 Tausend Jahren) während der letzten Eiszeit. in Central Europe based on multi-proxyProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. data from precisely dated speleothems (flowstones) from Bleßberg Cave, Germany

Project lead

Johannes Gutenberg University Mainz, Institute of Geosciences – Isotope-geochemical Palaeoclimatology/Speleothem Research

Involved Partners

Content

The last glacial period and in particular the Marine IsotopeIsotop Chemische Elemente können aus verschieden aufgebauten Atomen gebildet sein. Die Anzahl Protonen im Atomkern ist zwar dabei gleich, aber die Anzahl der Neutronen kann variieren. Man spricht dann von Isotopen, deren Massen kleine, aber messbare Unterschiede aufweisen. Der Atomkern des Sauerstoffs besteht z. B. aus 8 Protonen und in der Regel aus 8 Neutronen. Es gibt aber auch Sauerstoff, dessen Kerne aus 8 Protonen und 9 oder 10 Neutronen bestehen (neben selteneren, instabilen Sauerstoffisotopen). Um das zu kennzeichnen, gibt man zusätzlich zum chemischen Symbol noch die Massenzahl (Summe aus Protonen und Neutronen) an, also 16O, 17O oder 18O. Die unterschiedlichen Isotope verhalten sich zwar chemisch identisch, physikalisch aber - aufgrund ihres unterschiedlichen Gewichtes - leicht unterschiedlich. Damit stellen sie äusserst wertvolle Marker dar, die uns wichtige Hinweise zur Änderung des Klimas, der Umgebungsvegetation, Bodenaktivität und vielem mehr geben. Stage (MISMIS "MIS" ist die Abkürzung für "marine isotope stage", übersetzt also "Isotopenstadium mariner Sedimente". Da sich beim Wechsel von Warm- zu Kaltzeiten (und umgekehrt) die Isotopenverhältnisse in den Kalkschalen kleiner Einzeller (Foraminiferen) auf dem Meeresboden ändern, werden diese zur Datierung herangezogen und lassen sich zur Eingruppierung verschiedener Klimazustände in der Vergangenheit nutzen. Die MIS werden rückwärts nummeriert (also größere Zahl = älter) und ungerade Zahlen stehen für Warmzeiten, gerade für Kaltzeiten.) 3 (ca. 57 to 27 kaka BP Mit "ka BP" sind "Tausend Jahre vor 1950" gemeint. Das "BP" steht für "before present", was in der Paläoklima-Wissenschaft als 1950 festgelegt wurde. "11.000 ka BP" bedeuted also 11 Tausend Jahre vor 1950, oder unter Verwendung unseres gewohnten Kalenders: 9050 v. Chr.) is, compared to the recent warm phase, the Holocene, characterised by larger climate oscillations. These are detectable in δ18O records from Greenland ice cores and other climate archives in Europe, such as pollen or tree ring records. Unfortunately, little direct proxyProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. evidence is available from central Europe, and the climatic and environmental conditions during MIS 3 remains largely enigmatic. Speleothem records from central Europe during MIS 3 are limited due to cold climate conditions and mainly restricted to the warmer southern or alpine regions, where meltwater enabled speleothem growth.

Preliminary 230Th/UU/Th-Datierung Die U/Th-Datierung ist eine sehr präzise radiometrische Altersbestimmung auf Basis der Uran-Thorium-Zerfallsreihe. Das Uran zerfällt mit bekannten Halbwertszeiten (245.500 Jahre) zum Tochterelement Thorium. Stalagmiten bauen bei ihrem Wachstum (fast) nur das wasserlösliche Uran ein, während das schlecht bewegliche Thorium zum größten Teil im Boden und Epikarst über der Höhle verbleibt. Das kann man nutzen, um die Zeit zu berechnen, die seit der Ausfällung der untersuchten Karbonatprobe vergangen ist. Moderne massenspektrometrische Verfahren erlauben Altersbestimmungen mit der U/Th-Methode bis zu 700.000 Jahren vor Heute.-dating of further speleothems from Bleßberg Cave (Germany) revealed two flowstones, which grew during MIS 3 and the Late Glacial. Therefore, these flowstones are the most northern continental growth of speleothems during MIS 3 in central Europe.

The main objective of this project is to construct a precisely dated multi-proxy climate record for MIS 3 and the Late Glacial based on the flowstones from Bleßberg Cave. This will provide the unique opportunity to obtain precisely dated information on terrestrial climate variability during selected phases of the last glacial period, which is currently not available for Central Europe based on speleothems. With the combination of several different proxiesProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet., such as stable isotopes and trace elements, the results from a cave monitoring program, the analysis of the δD and δ¹⁸O values of inclusions of fossil water, and isotope-enabled climate modelling, we will be able to obtain detailed insights into environmental conditions in central Europe during MIS 3 and the Late Glacial.

Abrupt Climate Change

Posted on 9. April 20213. June 2021 by Norbert in Results

Klose, J.; Scholz, D.; Weber, M.; Vonhof, H.; Plessen, B.; Breitenbach, S.; Marwan, N.

Timing of Dansgaard-Oeschger events in Central Europe based on three precisely dated speleothems from Bleßberg Cave, Germany Proceedings

Poster, 2023, (Summer School on Speleothem Sciences 2023, Sao Paulo).

Abstract | Links | BibTeX

@proceedings{klose2023poster,

title = {Timing of Dansgaard-Oeschger events in Central Europe based on three precisely dated speleothems from Bleßberg Cave, Germany},

author = {J. Klose and D. Scholz and M. Weber and H. Vonhof and B. Plessen and S. Breitenbach and N. Marwan},

editor = {Summer School on Speleothem Sciences 2023, Sao Paulo},

url = {https://bbh.pik-potsdam.de/wp-content/uploads/2024/09/klose_SummerschoolSaoPaulo2023.pdf},

year  = {2023},

date = {2023-08-07},

urldate = {2023-08-07},

abstract = {The last glacial period and especially Marine Isotope stage 3 (MIS 3, ca. 57 - 27 ka) was characterized by various climate oscillations (i.e., rapid increases in temperature, followed by a gradual cooling, the Dansgaard-Oeschger (D/O) events), which were first discovered in Greenland ice cores. Although their causes are still not fully understood, clear evidence for their supra-regional character was found in various climate records around the globe. However, European speleothem samples, which grew during MIS 3, are limited and mainly restricted to alpine regions, where glacier meltwater enabled speleothem growth, and to south/south-western parts of Europe characterised by a generally warmer climate. This led to the opinion that it was too cold and/or too dry in central Europe for speleothem growth. Here we present three speleothem (flowstone) records from Bleßberg Cave, Germany, which grew during MIS 3. 

All flowstones show episodical growth patterns with distinctive, thin growth phases. Potential contamination deriving form detrital material deposited during hiatuses between individual growth phases, open-system behaviour around the hiatuses and the limited thickness of the growth layers are the biggest challenges during sampling for 230Th/U dating. By combination of different sampling techniques (i.e., laser ablation and micro-milling) in addition to the common approach of handheld drilling and due to the relatively high 238U concentration of the samples (approx. 0.4 – 1 µg/g), we were able to date even the thinnest growth layers (< 2 mm) of the Bleßberg flowstones with a very high precision (i.e., with 2σ-age uncertainties of a few hundred years or even lower).

The timing of the growth phases of the Bleßberg flowstones correlates with several D/O events recorded in the Greenland ice cores. This proves that at least some phases of MIS 3 had favourable climate conditions for speleothem growth in Central Europe. In addition, the analysis of the stable oxygen and carbon isotopes (δ18O and δ13C) for all three flowstones revealed several D/O events, which have not been recorded in any other speleothem from central Europe so far. This will enhance our understanding of climate variability during MIS 3 and specific D/O events in central Europe.},

howpublished = {Poster},

note = {Summer School on Speleothem Sciences 2023, Sao Paulo},

keywords = {},

pubstate = {published},

tppubtype = {proceedings}

}

Close

The last glacial period and especially Marine IsotopeIsotop Chemische Elemente können aus verschieden aufgebauten Atomen gebildet sein. Die Anzahl Protonen im Atomkern ist zwar dabei gleich, aber die Anzahl der Neutronen kann variieren. Man spricht dann von Isotopen, deren Massen kleine, aber messbare Unterschiede aufweisen. Der Atomkern des Sauerstoffs besteht z. B. aus 8 Protonen und in der Regel aus 8 Neutronen. Es gibt aber auch Sauerstoff, dessen Kerne aus 8 Protonen und 9 oder 10 Neutronen bestehen (neben selteneren, instabilen Sauerstoffisotopen). Um das zu kennzeichnen, gibt man zusätzlich zum chemischen Symbol noch die Massenzahl (Summe aus Protonen und Neutronen) an, also 16O, 17O oder 18O. Die unterschiedlichen Isotope verhalten sich zwar chemisch identisch, physikalisch aber - aufgrund ihres unterschiedlichen Gewichtes - leicht unterschiedlich. Damit stellen sie äusserst wertvolle Marker dar, die uns wichtige Hinweise zur Änderung des Klimas, der Umgebungsvegetation, Bodenaktivität und vielem mehr geben. stage 3 (MIS 3MIS 3 "MIS" ist die Abkürzung für "marine isotope stage", übersetzt also "Isotopenstadium mariner Sedimente". Da sich beim Wechsel von Warm- zu Kaltzeiten (und umgekehrt) die Isotopenverhältnisse in den Kalkschalen kleiner Einzeller (Foraminiferen) auf dem Meeresboden ändern, werden diese zur Datierung herangezogen und lassen sich zur Eingruppierung verschiedener Klimazustände in der Vergangenheit nutzen. "MIS 3" bedeutet dabei eine kurzzeitige Warmphase (beginnend vor 57 Tausend Jahren) während der letzten Eiszeit., ca. 57 - 27 kaka BP Mit "ka BP" sind "Tausend Jahre vor 1950" gemeint. Das "BP" steht für "before present", was in der Paläoklima-Wissenschaft als 1950 festgelegt wurde. "11.000 ka BP" bedeuted also 11 Tausend Jahre vor 1950, oder unter Verwendung unseres gewohnten Kalenders: 9050 v. Chr.) was characterized by various climate oscillations (i.e., rapid increases in temperature, followed by a gradual cooling, the Dansgaard-Oeschger (D/O) events), which were first discovered in Greenland ice cores. Although their causes are still not fully understood, clear evidence for their supra-regional character was found in various climate records around the globe. However, European speleothem samples, which grew during MIS 3, are limited and mainly restricted to alpine regions, where glacier meltwater enabled speleothem growth, and to south/south-western parts of Europe characterised by a generally warmer climate. This led to the opinion that it was too cold and/or too dry in central Europe for speleothem growth. Here we present three speleothem (flowstone) records from Bleßberg Cave, Germany, which grew during MIS 3.
All flowstones show episodical growth patterns with distinctive, thin growth phases. Potential contamination deriving form detrital material deposited during hiatuses between individual growth phases, open-system behaviour around the hiatuses and the limited thickness of the growth layers are the biggest challenges during sampling for 230Th/UU/Th-Datierung Die U/Th-Datierung ist eine sehr präzise radiometrische Altersbestimmung auf Basis der Uran-Thorium-Zerfallsreihe. Das Uran zerfällt mit bekannten Halbwertszeiten (245.500 Jahre) zum Tochterelement Thorium. Stalagmiten bauen bei ihrem Wachstum (fast) nur das wasserlösliche Uran ein, während das schlecht bewegliche Thorium zum größten Teil im Boden und Epikarst über der Höhle verbleibt. Das kann man nutzen, um die Zeit zu berechnen, die seit der Ausfällung der untersuchten Karbonatprobe vergangen ist. Moderne massenspektrometrische Verfahren erlauben Altersbestimmungen mit der U/Th-Methode bis zu 700.000 Jahren vor Heute. dating. By combination of different sampling techniques (i.e., laser ablation and micro-milling) in addition to the common approach of handheld drilling and due to the relatively high 238U concentration of the samples (approx. 0.4 – 1 µg/g), we were able to date even the thinnest growth layers (< 2 mm) of the Bleßberg flowstones with a very high precision (i.e., with 2σ-age uncertainties of a few hundred years or even lower).
The timing of the growth phases of the Bleßberg flowstones correlates with several D/O events recorded in the Greenland ice cores. This proves that at least some phases of MIS 3 had favourable climate conditions for speleothem growth in Central Europe. In addition, the analysis of the stable oxygen and carbon isotopes (δ18O and δ13C) for all three flowstones revealed several D/O events, which have not been recorded in any other speleothem from central Europe so far. This will enhance our understanding of climate variability during MIS 3 and specific D/O events in central Europe.

Close

Klose, J.; Scholz, D.; Weber, M.; Vonhof, H.; Plessen, B.; Breitenbach, S.; Marwan, N.

Timing and progression of Dansgaard-Oeschger events in Central Europe based on three precisely dated speleothems from Bleßberg Cave, Germany Proceedings

Poster, 2023, (XXI INQUA Conference, Rome (Italy)).

Abstract | BibTeX

@proceedings{klose2023,

title = {Timing and progression of Dansgaard-Oeschger events in Central Europe based on three precisely dated speleothems from Bleßberg Cave, Germany},

author = {J. Klose and D. Scholz and M. Weber and H. Vonhof and B. Plessen and S. Breitenbach and N. Marwan},

editor = {XXI INQUA Conference, Rome (Italy)},

year  = {2023},

date = {2023-07-19},

urldate = {2023-07-19},

abstract = {Speleothems can be dated with unprecedented precision using U-series disequilibrium methods and provide numerous climate proxies, such as stable oxygen (δ18O) and carbon isotopes (δ13C) or trace elements, resulting in long, sometimes continuous climate proxy records. Therefore, speleothems have great potential for reconstruction of past climate variability during Marine Isotope Stage (MIS) 3 and precise determination of the timing and duration of Dansgaard-Oeschger (D/O) events. While first discovered in Greenland ice cores, various speleothem records around the globe provided clear evidence for the supra-regional character of the D/O events. However, MIS 3 speleothem records from Central Europe are very limited. Here we present three spleothem (flowstone) MIS 3 records from Bleßberg Cave, Germany.



All flowstones show episodic growth with distinctive, partially very thin (<2 mm) growth phases, interrupted by visible hiatuses consisting of detrital material. Precise and accurate 230Th/U dating of the individual growth phases is challenging due to potential detrital contamination from these layers. Combining different sampling and analytical techniques, we were able to date even the thinnest growth layers with very high precision, i.e., 2σ-age uncertainties of at most a few hundred years.



The timing of the growth phases aligns with several D/O events, which have not been recorded in other Central European speleothems yet. The δ18O and δ13C records of all three flowstones are highly correlated which suggests a dominant process influencing both isotope systems. Comparison with the Sr and Mg records provides evidence for a strong influence of Prior Calcite Precipitation (PCP) in the aquifer above and inside the cave on the stable isotope and trace element signals. In addition, all proxy records are interpreted as evidence for past changes in precipitation and vegetation density and document a clear trend from more humid climate during early MIS 3 (ca. 57 – 50 ka) to less humid conditions during mid and late MIS 3 (ca. 45 – 30 ka).



Our multi-proxy approach thus allows us not only to precisely determine the timing, duration, and progression of several D/O events, but also to deepen our general understanding of climate variability during MIS 3 in Central Europe.},

howpublished = {Poster},

note = {XXI INQUA Conference, Rome (Italy)},

keywords = {},

pubstate = {published},

tppubtype = {proceedings}

}

Close

Speleothems can be dated with unprecedented precision using U-series disequilibrium methods and provide numerous climate proxiesProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet., such as stable oxygen (δ18O) and carbon isotopes (δ13C) or trace elements, resulting in long, sometimes continuous climate proxyProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. records. Therefore, speleothems have great potential for reconstruction of past climate variability during Marine Isotope Stage (MISMIS "MIS" ist die Abkürzung für "marine isotope stage", übersetzt also "Isotopenstadium mariner Sedimente". Da sich beim Wechsel von Warm- zu Kaltzeiten (und umgekehrt) die Isotopenverhältnisse in den Kalkschalen kleiner Einzeller (Foraminiferen) auf dem Meeresboden ändern, werden diese zur Datierung herangezogen und lassen sich zur Eingruppierung verschiedener Klimazustände in der Vergangenheit nutzen. Die MIS werden rückwärts nummeriert (also größere Zahl = älter) und ungerade Zahlen stehen für Warmzeiten, gerade für Kaltzeiten.) 3 and precise determination of the timing and duration of Dansgaard-Oeschger (D/O) events. While first discovered in Greenland ice cores, various speleothem records around the globe provided clear evidence for the supra-regional character of the D/O events. However, MIS 3 speleothem records from Central Europe are very limited. Here we present three spleothem (flowstone) MIS 3 records from Bleßberg Cave, Germany.

All flowstones show episodic growth with distinctive, partially very thin (<2 mm) growth phases, interrupted by visible hiatuses consisting of detrital material. Precise and accurate 230Th/U dating of the individual growth phases is challenging due to potential detrital contamination from these layers. Combining different sampling and analytical techniques, we were able to date even the thinnest growth layers with very high precision, i.e., 2σ-age uncertainties of at most a few hundred years.

The timing of the growth phases aligns with several D/O events, which have not been recorded in other Central European speleothems yet. The δ18O and δ13C records of all three flowstones are highly correlated which suggests a dominant process influencing both isotope systems. Comparison with the Sr and Mg records provides evidence for a strong influence of Prior Calcite Precipitation (PCP) in the aquifer above and inside the cave on the stable isotope and trace element signals. In addition, all proxy records are interpreted as evidence for past changes in precipitation and vegetation density and document a clear trend from more humid climate during early MIS 3 (ca. 57 – 50 ka) to less humid conditions during mid and late MIS 3 (ca. 45 – 30 ka).

Our multi-proxyProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. approach thus allows us not only to precisely determine the timing, duration, and progression of several D/O events, but also to deepen our general understanding of climate variability during MIS 3 in Central Europe.

Close

Klose, J.; Weber, M.; Vonhof, H.; Plessen, B.; Breitenbach, S.; Marwan, N.; Scholz, D.

Timing of Dansgaard-Oeschger events in Central Europe based on three precisely dated speleothems from Bleßberg Cave, Germany Proceedings

Poster, 2022, (KR9 Konferenz in Innsbruck).

Abstract | Links | BibTeX

@proceedings{klose2022,

title = {Timing of Dansgaard-Oeschger events in Central Europe based on three precisely dated speleothems from Bleßberg Cave, Germany},

author = {J. Klose and M. Weber and H. Vonhof and B. Plessen and S. Breitenbach and N. Marwan and D. Scholz},

editor = {KR9 in Innsbruck, 2022},

url = {https://bbh.pik-potsdam.de/wp-content/uploads/2024/09/klose_KR9-Innsbruck2022.pdf},

year  = {2022},

date = {2022-07-19},

urldate = {2022-07-19},

abstract = {The last glacial period and especially Marine Isotope stage 3 (MIS 3, ca. 57 - 27 ka) was characterized by various climate oscillations (i.e., rapid increases in temperature, followed by a gradual cooling, the Dansgaard-Oeschger (D/O) events), which were first discovered in Greenland ice cores. Although their causes are still not fully understood, clear evidence for their supra-regional character was found in various climate records around the globe. However, European speleothem samples, which grew during MIS 3, are limited and mainly restricted to alpine regions, where glacier meltwater enabled speleothem growth, and to south/south-western parts of Europe characterised by a generally warmer climate. This led to the opinion that it was too cold and/or too dry in central Europe for speleothem growth. Here we present three speleothem (flowstone) records from Bleßberg Cave, Germany, which grew during MIS 3. 

All flowstones show episodical growth patterns with distinctive, thin growth phases. Potential contamination deriving form detrital material deposited during hiatuses between individual growth phases, open-system behaviour around the hiatuses and the limited thickness of the growth layers are the biggest challenges during sampling for 230Th/U dating. By combination of different sampling techniques (i.e., laser ablation and micro-milling) in addition to the common approach of handheld drilling and due to the relatively high 238U concentration of the samples (approx. 0.4 – 1 µg/g), we were able to date even the thinnest growth layers (< 2 mm) of the Bleßberg flowstones with a very high precision (i.e., with 2σ-age uncertainties of a few hundred years or even lower).

The timing of the growth phases of the Bleßberg flowstones correlates with several D/O events recorded in the Greenland ice cores. This proves that at least some phases of MIS 3 had favourable climate conditions for speleothem growth in Central Europe. In addition, the analysis of the stable oxygen and carbon isotopes (δ18O and δ13C) for all three flowstones revealed several D/O events, which have not been recorded in any other speleothem from central Europe so far. This will enhance our understanding of climate variability during MIS 3 and specific D/O events in central Europe.},

howpublished = {Poster},

note = {KR9 Konferenz in Innsbruck},

keywords = {},

pubstate = {published},

tppubtype = {proceedings}

}

Close

The last glacial period and especially Marine Isotope stage 3 (MIS 3, ca. 57 - 27 ka) was characterized by various climate oscillations (i.e., rapid increases in temperature, followed by a gradual cooling, the Dansgaard-Oeschger (D/O) events), which were first discovered in Greenland ice cores. Although their causes are still not fully understood, clear evidence for their supra-regional character was found in various climate records around the globe. However, European speleothem samples, which grew during MIS 3, are limited and mainly restricted to alpine regions, where glacier meltwater enabled speleothem growth, and to south/south-western parts of Europe characterised by a generally warmer climate. This led to the opinion that it was too cold and/or too dry in central Europe for speleothem growth. Here we present three speleothem (flowstone) records from Bleßberg Cave, Germany, which grew during MIS 3.
All flowstones show episodical growth patterns with distinctive, thin growth phases. Potential contamination deriving form detrital material deposited during hiatuses between individual growth phases, open-system behaviour around the hiatuses and the limited thickness of the growth layers are the biggest challenges during sampling for 230Th/U dating. By combination of different sampling techniques (i.e., laser ablation and micro-milling) in addition to the common approach of handheld drilling and due to the relatively high 238U concentration of the samples (approx. 0.4 – 1 µg/g), we were able to date even the thinnest growth layers (< 2 mm) of the Bleßberg flowstones with a very high precision (i.e., with 2σ-age uncertainties of a few hundred years or even lower).
The timing of the growth phases of the Bleßberg flowstones correlates with several D/O events recorded in the Greenland ice cores. This proves that at least some phases of MIS 3 had favourable climate conditions for speleothem growth in Central Europe. In addition, the analysis of the stable oxygen and carbon isotopes (δ18O and δ13C) for all three flowstones revealed several D/O events, which have not been recorded in any other speleothem from central Europe so far. This will enhance our understanding of climate variability during MIS 3 and specific D/O events in central Europe.

Close

Marwan, Norbert

Bleßberghöhle – Schatzkammer für die Wissenschaft Presentation

15.06.2022, (VdHK-Symposium: Wissenschaft unter Tage – Höhlenforschung im Dialog, Truckenthal (Germany)).

BibTeX

Breitenbach, Sebastian F. M.; Marwan, Norbert

Die Bleßberghöhle – ein Glücksfall für die Klimaforschung Book Section

In: Thüringer Höhlenverein, e. V. (Ed.): Nächster Halt: Bleßberghöhle, Suhl, 2022.

Abstract | BibTeX

Marwan, Norbert; Breitenbach, Sebastian F. M.; Plessen, Birgit; Scholz, Denis; Leonhardt, Jens

Recurrence properties as signatures for abrupt climate change Proceedings Article

In: Geophysical Research Abstracts, pp. EGU2014-8893, 2014.

Abstract | Links | BibTeX

Among other things, new methods are being developed at PIK that, on the one hand, investigate new aspects in palaeoclimate data, but also cope with the difficulties usually associated with palaeoclimate analyses – such as gaps in the data, age uncertainties, or irregularities in the data sampling. While this is basic research, it is also immediately applied to interesting research questions.

One focus is the development and application of methods that specifically investigate recurring patterns. These methods are very successful for finding abrupt changes, but also for comparing different data sets, e.g., to detect mutual influences.

In one of our first analyses of the three stalagmites BB-1 to BB-3, we had looked at the oxygen isotopes of BB-1 with recurrence based methods. Thereby we had explicitly considered dating uncertainties. Due to the dating uncertainties there are small shifts of the time series along the x-axis. Therefore, within the uncertainties, different realizations of the course of the measured oxygen isotopes are possible.

Sauerstoffisotope von BB-1 — Oxygen isotopes of BB-1. Due to the dating uncertainties, there are several possibilities when changes in this climate archive happened. The stalagmite grew from about 6,000 years ago to about 400 years ago.

The recurrence patterns are examined with a special analysis tool, the so-called “recurrence plot”. This can be used to plot times when similar states have occurred. The patterns seen in such a recurrence plot have a deeper meaning and can be further analyzed and quantified to find changes in the dynamics of the underlying process.

Recurrence plot der Sauerstoffisotope von BB-1 — Recurrence plot of one realization of the measured oxygen isotopes in BB-1.

The numerical analysis of recurrence plots yields various results that shed light on different aspects of climate dynamics. Two such results are briefly presented here: on the one hand, the complexity of climate variability (“transitivityTransitivity Ein Maß aus der Netzwerktheorie, welches quantifiziert, wie stark sich Zustände zu kleinen Gruppen zusammenfinden.”) and, on the other hand, how well such a climate signal would be predictable (“determinismDeterminism Ein Maß aus der Wiederkehr-Analyse, welches beschreibt, wie gut sich die Veränderung eines Systems vorhersagen läßt.”). Both results show a general tendency towards greater complexity and lower predictability for younger ages. However, they also show short-lived increases to better predictability for certain time points, namely about 4,200, 2,800, and 1,400 years ago. It was precisely at these times that short-lived and rapid glaciations occurred in the North Atlantic, the so-called “Bond events.” Moreover, there are variations in the complexity of the climate signal (“transitivity”), but these variations are within the range of uncertainty (confidence interval), so we cannot really interpret them.

Recurrence quantification der Sauerstoffisotope von BB-1 — Quantitative analysis of recurrence patterns in oxygen isotope measurements of BB-1.

Climate Zone Shift in central Europe

Posted on 9. April 20213. June 2021 by Norbert in Results

Marwan, Norbert

Bleßberghöhle – Schatzkammer für die Wissenschaft Presentation

15.06.2022, (VdHK-Symposium: Wissenschaft unter Tage – Höhlenforschung im Dialog, Truckenthal (Germany)).

BibTeX

Breitenbach, Sebastian F. M.; Marwan, Norbert

Die Bleßberghöhle – ein Glücksfall für die Klimaforschung Book Section

In: Thüringer Höhlenverein, e. V. (Ed.): Nächster Halt: Bleßberghöhle, Suhl, 2022.

Abstract | BibTeX

Breitenbach, Sebastian F. M.; Plessen, Birgit; Waltgenbach, Sarah; Tjallingii, Rik; Leonhardt, Jens; Jochum, Klaus-Peter; Meyer, Hanno; Goswami, Bedartha; Marwan, Norbert; Scholz, Denis

Holocene interaction of maritime and continental climate in Central Europe: New speleothem evidence from Central Germany Journal Article

In: Global and Planetary Change, vol. 176, pp. 144–161, 2019.

Abstract | Links | BibTeX

@article{breitenbach2019,

title = {Holocene interaction of maritime and continental climate in Central Europe: New speleothem evidence from Central Germany},

author = {Sebastian F. M. Breitenbach and Birgit Plessen and Sarah Waltgenbach and Rik Tjallingii and Jens Leonhardt and Klaus-Peter Jochum and Hanno Meyer and Bedartha Goswami and Norbert Marwan and Denis Scholz},

doi = {10.1016/j.gloplacha.2019.03.007},

year  = {2019},

date = {2019-00-00},

journal = {Global and Planetary Change},

volume = {176},

pages = {144–161},

abstract = {Central European climate is strongly influenced by North Atlantic (Westerlies) and Siberian High circulation patterns, which govern precipitation and temperature dynamics and induce heterogeneous climatic conditions, with distinct boundaries between climate zones. These climate boundaries are not stationary and shift geographically, depending on long-term atmospheric conditions. So far, little is known about past shifts of these climate boundaries and the local to regional environmental response prior to the instrumental era.



High resolution multi-proxy data (stable oxygen and carbon isotope ratios, S/Ca and Sr/Ca) from two Holocene stalagmites from Bleßberg Cave (Thuringia) are used here to differentiate local and pan-regional environmental and climatic conditions Central Germany through the Holocene. Carbon isotope and S/Ca and Sr/Ca ratios inform us on local Holocene environmental changes in and around the cave, while δ18O (when combined with independent records) serves as proxy for (pan-)regional atmospheric conditions.



The stable carbon isotope record suggests repeated changes in vegetation density (open vs. dense forest), and increasing forest cover in the late Holocene. Concurrently, decreasing S/Ca values indicate more effective sulfur retention in better developed soils, with a stabilization in the mid-Holocene. This goes in hand with changes in effective summer infiltration, reflected in the Sr/Ca profile. Highest Sr/Ca values between 4 ka and 1 ka BP indicate intensified prior calcite precipitation resulting from reduced effective moisture supply.



The region of Bleßberg Cave is sensitive to shifts of the boundary between maritime (Cfb) and continental (Dfb) climate and ideally suited to reconstruct past meridional shifts of this divide. We combined the Bleßberg Cave δ18O time series with δ18O data from Bunker Cave (western Germany) and a North Atlantic Oscillation (NAO) record from lake SS1220 (SW Greenland) to reconstruct the mean position of the Cfb-Dfb climate boundary. We further estimate the dynamic interplay of the North Atlantic Oscillation and the Siberian High and their influence on Central European climate. Repeated shifts of the Cfb-Dfb boundary over the last 4000 years might explain previously observed discrepancies between proxy records from Europe. Detailed correlation analyses reveal multi-centennial scale alternations of maritime and continental climate and, concurrently, waning and waxing influences of Siberian High and NAO on Central Europe.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

Close

Central European climate is strongly influenced by North Atlantic (Westerlies) and Siberian High circulation patterns, which govern precipitation and temperature dynamics and induce heterogeneous climatic conditions, with distinct boundaries between climate zones. These climate boundaries are not stationary and shift geographically, depending on long-term atmospheric conditions. So far, little is known about past shifts of these climate boundaries and the local to regional environmental response prior to the instrumental era.

High resolution multi-proxyProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. data (stable oxygen and carbon isotopeIsotop Chemische Elemente können aus verschieden aufgebauten Atomen gebildet sein. Die Anzahl Protonen im Atomkern ist zwar dabei gleich, aber die Anzahl der Neutronen kann variieren. Man spricht dann von Isotopen, deren Massen kleine, aber messbare Unterschiede aufweisen. Der Atomkern des Sauerstoffs besteht z. B. aus 8 Protonen und in der Regel aus 8 Neutronen. Es gibt aber auch Sauerstoff, dessen Kerne aus 8 Protonen und 9 oder 10 Neutronen bestehen (neben selteneren, instabilen Sauerstoffisotopen). Um das zu kennzeichnen, gibt man zusätzlich zum chemischen Symbol noch die Massenzahl (Summe aus Protonen und Neutronen) an, also 16O, 17O oder 18O. Die unterschiedlichen Isotope verhalten sich zwar chemisch identisch, physikalisch aber - aufgrund ihres unterschiedlichen Gewichtes - leicht unterschiedlich. Damit stellen sie äusserst wertvolle Marker dar, die uns wichtige Hinweise zur Änderung des Klimas, der Umgebungsvegetation, Bodenaktivität und vielem mehr geben. ratios, S/Ca and Sr/Ca) from two Holocene stalagmites from Bleßberg Cave (Thuringia) are used here to differentiate local and pan-regional environmental and climatic conditions Central Germany through the Holocene. Carbon isotope and S/Ca and Sr/Ca ratios inform us on local Holocene environmental changes in and around the cave, while δ18O (when combined with independent records) serves as proxyProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. for (pan-)regional atmospheric conditions.

The stable carbon isotope record suggests repeated changes in vegetation density (open vs. dense forest), and increasing forest cover in the late Holocene. Concurrently, decreasing S/Ca values indicate more effective sulfur retention in better developed soils, with a stabilization in the mid-Holocene. This goes in hand with changes in effective summer infiltration, reflected in the Sr/Ca profile. Highest Sr/Ca values between 4 kaka BP Mit "ka BP" sind "Tausend Jahre vor 1950" gemeint. Das "BP" steht für "before present", was in der Paläoklima-Wissenschaft als 1950 festgelegt wurde. "11.000 ka BP" bedeuted also 11 Tausend Jahre vor 1950, oder unter Verwendung unseres gewohnten Kalenders: 9050 v. Chr. and 1 ka BPka BP Mit "ka BP" sind "Tausend Jahre vor 1950" gemeint. Das "BP" steht für "before present", was in der Paläoklima-Wissenschaft als 1950 festgelegt wurde. "11.000 ka BP" bedeuted also 11 Tausend Jahre vor 1950, oder unter Verwendung unseres gewohnten Kalenders: 9050 v. Chr. indicate intensified prior calcite precipitation resulting from reduced effective moisture supply.

The region of Bleßberg Cave is sensitive to shifts of the boundary between maritime (Cfb) and continental (Dfb) climate and ideally suited to reconstruct past meridional shifts of this divide. We combined the Bleßberg Cave δ18O time series with δ18O data from Bunker Cave (western Germany) and a North Atlantic Oscillation (NAO) record from lake SS1220 (SW Greenland) to reconstruct the mean position of the Cfb-Dfb climate boundary. We further estimate the dynamic interplay of the North Atlantic Oscillation and the Siberian High and their influence on Central European climate. Repeated shifts of the Cfb-Dfb boundary over the last 4000 years might explain previously observed discrepancies between proxy records from Europe. Detailed correlation analyses reveal multi-centennial scale alternations of maritime and continental climate and, concurrently, waning and waxing influences of Siberian High and NAO on Central Europe.

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Breitenbach, Sebastian F. M.; Plessen, Birgit; Wenz, Sarah; Leonhardt, Jens; Tjallingii, Rik; Scholz, Denis; Jochum, Klaus-Peter; Marwan, Norbert

A multi-proxy reconstruction of Holocene climate change from Blessberg Cave, Germany Proceedings Article

In: Geophysical Research Abstracts, pp. EGU2016-14213, 2016.

Abstract | Links | BibTeX

@inproceedings{breitenbach2016,

title = {A multi-proxy reconstruction of Holocene climate change from Blessberg Cave, Germany},

author = {Sebastian F. M. Breitenbach and Birgit Plessen and Sarah Wenz and Jens Leonhardt and Rik Tjallingii and Denis Scholz and Klaus-Peter Jochum and Norbert Marwan},

url = {https://bbh.pik-potsdam.de/wp-content/uploads/2021/05/Breitenbach_poster_EGU_2016.pdf},

year  = {2016},

date = {2016-04-01},

booktitle = {Geophysical Research Abstracts},

volume = {18},

pages = {EGU2016-14213},

abstract = {Although Holocene climate dynamics were relatively stable compared to glacial conditions, climatic changes had significant impact on ecosystems and human society on various timescales (Mayewski et al. 2004, Donges et al. 2015, Tan et al. 2015). Precious few high-resolution records on Holocene temperature and precipitation conditions in Central Europe are available (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012).

Here we present a speleothem-based reconstruction of past climate dynamics from Blessberg Cave, Thuringia, central Germany. Three calcitic stalagmites were recovered when the cave was discovered during tunneling operations in 2008. Samples BB-1, -2 and -3 were precisely dated by the 230Th/U-method, with errors between 10 and 160 years (2σ). The combined record covers large parts of the Holocene (10 – 0.4 ka BP). δ13C and δ18O were analysed at 100 μm resolution. To gain additional insights in infiltration conditions, Sr/Ca and S/Ca were measured on BB-1 and BB-3 using an Röntgenanalytik Eagle XXL μXRF scanner.

Differences to other central European records (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012) suggest complex interaction between multiple factors influencing speleothem δ18O in Blessberg Cave. Furthermore, no clear influence of the North Atlantic Oscillation on our proxies is found. However, a link across the N Atlantic realm is indicated by a centennial-scale correlation between Blessberg δ18O values and minerogenic input into lake SS1220 in Greenland over the last 5 ka (Olsen et al. 2012). In addition, recurrence analysis indicates an imprint of Atlantic Bond events on Blessberg δ18O values (Marwan et al. 2014), corroborating the suggested link with high northern latitudes. Larger runoff into the Greenland lake seems to be associated with lower δ18O, higher δ13C and S/Ca ratios, as well as lower Sr/Ca ratios in Blessberg Cave speleothems. This might be linked to lower local temperature and/or changes in precipitation seasonality. Opposing millennial scale trends with lowering S/Ca ratios and δ13C values but increasing Sr/Ca ratios calls for more than one controlling factor. Most likely, δ13C decreased through the Holocene due to afforestation, which in turn might have increased sulphate retention in the thickening soil cover (Frisia et al. 2005) and limited sulphur flux into the cave. Alternatively, marine sulfur flux could have diminished with winter wind intensities. However, additional data is required to clarify this hypothesis. A positive Sr/Ca trend through the Holocene might result from increasing prior calcite precipitation induced by a negative moisture balance in summer.},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

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Although Holocene climate dynamics were relatively stable compared to glacial conditions, climatic changes had significant impact on ecosystems and human society on various timescales (Mayewski et al. 2004, Donges et al. 2015, Tan et al. 2015). Precious few high-resolution records on Holocene temperature and precipitation conditions in Central Europe are available (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012).
Here we present a speleothem-based reconstruction of past climate dynamics from Blessberg Cave, Thuringia, central Germany. Three calcitic stalagmites were recovered when the cave was discovered during tunneling operations in 2008. Samples BB-1, -2 and -3 were precisely dated by the 230Th/UU/Th-Datierung Die U/Th-Datierung ist eine sehr präzise radiometrische Altersbestimmung auf Basis der Uran-Thorium-Zerfallsreihe. Das Uran zerfällt mit bekannten Halbwertszeiten (245.500 Jahre) zum Tochterelement Thorium. Stalagmiten bauen bei ihrem Wachstum (fast) nur das wasserlösliche Uran ein, während das schlecht bewegliche Thorium zum größten Teil im Boden und Epikarst über der Höhle verbleibt. Das kann man nutzen, um die Zeit zu berechnen, die seit der Ausfällung der untersuchten Karbonatprobe vergangen ist. Moderne massenspektrometrische Verfahren erlauben Altersbestimmungen mit der U/Th-Methode bis zu 700.000 Jahren vor Heute.-method, with errors between 10 and 160 years (2σ). The combined record covers large parts of the Holocene (10 – 0.4 ka BP). δ13C and δ18O were analysed at 100 μm resolution. To gain additional insights in infiltration conditions, Sr/Ca and S/Ca were measured on BB-1 and BB-3 using an Röntgenanalytik Eagle XXL μXRF scanner.
Differences to other central European records (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012) suggest complex interaction between multiple factors influencing speleothem δ18O in Blessberg Cave. Furthermore, no clear influence of the North Atlantic Oscillation on our proxiesProxy Umwelt- und Klimainformationen aus der Vergangenheit sind nicht direkt verfügbar, weil niemand da war, der diese messen und aufzeichnen konnte. Daher ist man darauf angewiesen, diese Informationen indirekt aus anderen Informationen abzuleiten, wie z. B. Baumringe, das Verhältnis von Sauerstoffisotopen, Spurenelementen, Mächtigkeit von Sedimentschichten usw. Diese Art von Daten nennt man Proxies, was aus dem englischen stammt und „Stellvertreter“ bedeutet. is found. However, a link across the N Atlantic realm is indicated by a centennial-scale correlation between Blessberg δ18O values and minerogenic input into lake SS1220 in Greenland over the last 5 ka (Olsen et al. 2012). In addition, recurrence analysis indicates an imprint of Atlantic Bond events on Blessberg δ18O values (Marwan et al. 2014), corroborating the suggested link with high northern latitudes. Larger runoff into the Greenland lake seems to be associated with lower δ18O, higher δ13C and S/Ca ratios, as well as lower Sr/Ca ratios in Blessberg Cave speleothems. This might be linked to lower local temperature and/or changes in precipitation seasonality. Opposing millennial scale trends with lowering S/Ca ratios and δ13C values but increasing Sr/Ca ratios calls for more than one controlling factor. Most likely, δ13C decreased through the Holocene due to afforestation, which in turn might have increased sulphate retention in the thickening soil cover (Frisia et al. 2005) and limited sulphur flux into the cave. Alternatively, marine sulfur flux could have diminished with winter wind intensities. However, additional data is required to clarify this hypothesis. A positive Sr/Ca trend through the Holocene might result from increasing prior calcite precipitation induced by a negative moisture balance in summer.

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The three stalagmites BB-1 to BB-3 were geochemically investigated by GFZ Potsdam, Ruhr-Uni Bochum, PIK Potsdam, Uni Mainz and Northumbria University.

The dating was done at the University of Mainz. Stalagmite BB-1 grew 5,600 to 600 years ago, BB-2 6,200 to 3,700 years ago, and BB-3 (although the shortest) 11,200 to 5,300 years ago. At GFZ, carbon and oxygen isotopes (δ¹³C and δ¹⁸O) were measured in over 1,000 samples in BB-1, and about 400 and 540 samples each in BB-2 and BB-3. In parallel, the distribution of various elements was measured by X-ray analysis. Age modelling and statistical analysis were carried out at Ruhr-Uni Bochum, PIK Potsdam and Northumbria University.

In the age models of stalagmites BB-1 and BB-3, abrupt changes from slow to fast growth are evident at about 5,900 BC and from fast to more slow growth at about 2,600 BC.

Age models of stalagmites BB-1 and BB-3. Changes in growth rates at around 6,200 BC and between 5,900 and 2,600 BC can clearly be seen, for which climatic changes are responsible.

The temporal changes in isotope ratios were compared with palaeoclimate data from the Bunker Cave in North Rhine-Westphalia and from Greenland.

Isotope ratios in stalagmites BB-1 and BB-3 (combined). The longer-term trends probably reflect a change in solar influence. The short-term climate cooling around 6,200 BC is clearly visible in the isotope ratios. The abrupt drop in δ18O values around 900 to 1,200 AD coincides with the Medieval Warm Period.

This comparison allows an estimation of the spatial distribution of the influence of the maritime, humid and warm Atlantic climate in Central Europe. The Blessberg cave is located at the border between the influence of the Atlantic climate and the continental, drier and colder climate from the east. From the alternation between stronger similarities and greater differences in the regional climate at the Blessberg Cave and the Bunker Cave it can be determined when the climate zone boundary was east or west of the Bleßberg Cave, i.e. when the Atlantic, wetter and warmer climate and when the colder and drier continental climate prevailed over the Bleßberg Cave. This analysis could be carried out back to about 4,000 years ago (i.e. about 2050 BC). Before this time, due to the lack of data from Greenland, it is not yet possible to make conclusions regarding the location of the climate zone boundary, but at least around this time the Bleßberg Cave was probably under the influence of the Atlantic climate. Around 1850 BC it then changed to a continental climate (in the late Aunjetitz culture, known from the Nebra sky disc). Between 950 and 850 BC, the Atlantic influence became more dominant again (towards the end of the Urnfield Culture).

Shift of the climate zone boundary (dashed) to the east with hypothetical course (dotted) at the time of the Urnfield Culture (BU – Bunker Cave, BBH – Blessberg Cave).