Abrupt Climate Change at the End of the Last Glacial Period Inferred from Trapped Air in Polar Ice

Science ◽  
1999 ◽  
Vol 286 (5441) ◽  
pp. 930-934 ◽  
Author(s):  
J. P. Severinghaus
Keyword(s):  
Climate Change ◽  
Abrupt Climate Change ◽  
Glacial Period ◽  
Polar Ice ◽  
Last Glacial Period ◽  
Last Glacial ◽  
Trapped Air ◽  
The Last Glacial

Diatom assemblage dynamics during abrupt climate change: the response of lacustrine diatoms to Dansgaard–Oeschger cycles during the last glacial period

2009 ◽  
Vol 44 (2) ◽  
pp. 397-404 ◽  
Author(s):  
Linda Ampel ◽  
Barbara Wohlfarth ◽  
Jan Risberg ◽  
Daniel Veres ◽  
Melanie J. Leng ◽  
...  
Keyword(s):  
Climate Change ◽  
Diatom Assemblage ◽  
Abrupt Climate Change ◽  
Glacial Period ◽  
Last Glacial Period ◽  
Last Glacial ◽  
The Last Glacial

Possible role of dust-induced regional warming in abrupt climate change during the last glacial period

Nature ◽  
1996 ◽  
Vol 384 (6608) ◽  
pp. 447-449 ◽  
Author(s):  
Jonathan Overpeck ◽  
David Rind ◽  
Andrew Lacis ◽  
Richard Healy
Keyword(s):  
Climate Change ◽  
Abrupt Climate Change ◽  
Glacial Period ◽  
Regional Warming ◽  
Last Glacial Period ◽  
Last Glacial ◽  
The Last Glacial

scholarly journals Bipolar volcanic synchronization of abrupt climate change in Greenland and Antarctic ice cores during the last glacial period

2020 ◽  
Author(s):  
Anders Svensson ◽  
Dorthe Dahl-Jensen ◽  
Jørgen Peder Steffensen ◽  
Thomas Blunier ◽  
Sune O. Rasmussen ◽  
...  
Keyword(s):  
Climate Change ◽  
Ice Core ◽  
Ice Cores ◽  
Volcanic Eruptions ◽  
Abrupt Climate Change ◽  
Glacial Period ◽  
Deuterium Excess ◽  
Last Glacial Period ◽  
Last Glacial ◽  
The Last Glacial

Abstract. The last glacial period is characterized by a number of abrupt climate events that have been identified in both Greenland and Antarctic ice cores. The mechanisms governing this climate variability remain a puzzle that requires a precise synchronization of ice cores from the two Hemispheres to be resolved. Previously, Greenland and Antarctic ice cores have been synchronized primarily via their common records of gas concentrations or isotopes from the trapped air and via cosmogenic isotopes measured on the ice. In this work, we apply ice-core volcanic proxies and annual layer counting to identify large volcanic eruptions that have left a signature in both Greenland and Antarctica. Generally, no tephra is associated with those eruptions in the ice cores, so the source of the eruptions cannot be identified. Instead, we identify and match sequences of volcanic eruptions with bipolar distribution of sulfate, i.e. unique patterns of volcanic events separated by the same number of years at the two poles. Using this approach, we pinpoint 80 large bipolar volcanic eruptions throughout the second half of the last glacial period (12–60 ka before present). This improved ice-core synchronization is applied to determine the bipolar phasing of abrupt climate change events at decadal-scale precision. During abrupt transitions, we find more coherent Antarctic water isotopic signals (δ18O and deuterium excess) than was obtained from previous gas-based synchronizations, providing additional support for our volcanic framework. On average, the Antarctic bipolar seesaw climate response lags the midpoint of Greenland abrupt δ18O transitions by 122 ± 24 years. The time difference between Antarctic signals in deuterium excess and δ18O, which is less sensitive to synchronization errors, suggests an Antarctic δ18O lag of 152 ± 37 years. These estimates are shorter than the 200 years suggested by earlier gas-based synchronizations. As before, we find variations in the timing and duration between the response at different sites and for different events suggesting an interaction of oceanic and atmospheric teleconnection patterns as well as internal climate variability.

scholarly journals <i>δ</i><sup>13</sup>C decreases in the upper western South Atlantic during Heinrich Stadials 3 and 2

2017 ◽  
Vol 13 (4) ◽  
pp. 345-358 ◽  
Author(s):  
Marília C. Campos ◽  
Cristiano M. Chiessi ◽  
Ines Voigt ◽  
Alberto R. Piola ◽  
Henning Kuhnert ◽  
...  
Keyword(s):  
Climate Change ◽  
South Atlantic ◽  
Meridional Overturning Circulation ◽  
Glacial Period ◽  
Last Deglaciation ◽  
Last Glacial Period ◽  
Last Glacial ◽  
Change Events ◽  
The Last Glacial ◽  
Millennial Scale

Abstract. Abrupt millennial-scale climate change events of the last deglaciation (i.e. Heinrich Stadial 1 and the Younger Dryas) were accompanied by marked increases in atmospheric CO2 (CO2atm) and decreases in its stable carbon isotopic ratios (δ13C), i.e. δ13CO2atm, presumably due to outgassing from the ocean. However, information on the preceding Heinrich Stadials during the last glacial period is scarce. Here we present δ13C records from two species of planktonic foraminifera from the western South Atlantic that reveal major decreases (up to 1 ‰) during Heinrich Stadials 3 and 2. These δ13C decreases are most likely related to millennial-scale periods of weakening of the Atlantic meridional overturning circulation and the consequent increase (decrease) in CO2atm (δ13CO2atm). We hypothesise two mechanisms that could account for the decreases observed in our records, namely strengthening of Southern Ocean deep-water ventilation and weakening of the biological pump. Additionally, we suggest that air–sea gas exchange could have contributed to the observed δ13C decreases. Together with other lines of evidence, our data are consistent with the hypothesis that the CO2 added to the atmosphere during abrupt millennial-scale climate change events of the last glacial period also originated in the ocean and reached the atmosphere by outgassing. The temporal evolution of δ13C during Heinrich Stadials 3 and 2 in our records is characterized by two relative minima separated by a relative maximum. This w structure is also found in North Atlantic and South American records, further suggesting that such a structure is a pervasive feature of Heinrich Stadial 2 and, possibly, also Heinrich Stadial 3.

Sign in / Sign up

Export Citation Format

Share Document