Changes in decadal variability and depositional flux of aerosol constituents recorded in the EPICA Dome C ice core beyond the last interglacial period

Abstract. The last interglacial period (LIG, ∼ 129–116 thousand years ago) provides the most recent case study of multimillennial polar warming above the preindustrial level and a response of the Greenland and Antarctic ice sheets to this warming, as well as a test bed for climate and ice sheet models. Past changes in Greenland ice sheet thickness and surface temperature during this period were recently derived from the North Greenland Eemian Ice Drilling (NEEM) ice core records, northwest Greenland. The NEEM paradox has emerged from an estimated large local warming above the preindustrial level (7.5 ± 1.8 °C at the deposition site 126 kyr ago without correction for any overall ice sheet altitude changes between the LIG and the preindustrial period) based on water isotopes, together with limited local ice thinning, suggesting more resilience of the real Greenland ice sheet than shown in some ice sheet models. Here, we provide an independent assessment of the average LIG Greenland surface warming using ice core air isotopic composition (δ15N) and relationships between accumulation rate and temperature. The LIG surface temperature at the upstream NEEM deposition site without ice sheet altitude correction is estimated to be warmer by +8.5 ± 2.5 °C compared to the preindustrial period. This temperature estimate is consistent with the 7.5 ± 1.8 °C warming initially determined from NEEM water isotopes but at the upper end of the preindustrial period to LIG temperature difference of +5.2 ± 2.3 °C obtained at the NGRIP (North Greenland Ice Core Project) site by the same method. Climate simulations performed with present-day ice sheet topography lead in general to a warming smaller than reconstructed, but sensitivity tests show that larger amplitudes (up to 5 °C) are produced in response to prescribed changes in sea ice extent and ice sheet topography.

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A brief history of ice core science over the last 50 yr

Climate of the Past ◽

10.5194/cp-9-2525-2013 ◽

2013 ◽

Vol 9 (6) ◽

pp. 2525-2547 ◽

Cited By ~ 41

Author(s):

J. Jouzel

Keyword(s):

Time Scales ◽

Environmental Changes ◽

Ice Core ◽

Ice Cores ◽

Future Research ◽

Interglacial Period ◽

Last Interglacial ◽

Last Interglacial Period ◽

History Of ◽

Scientific Results

Abstract. For about 50 yr, ice cores have provided a wealth of information about past climatic and environmental changes. Ice cores from Greenland, Antarctica and other glacier-covered regions now encompass a variety of time scales. However, the longer time scales (e.g. at least back to the Last Glacial period) are covered by deep ice cores, the number of which is still very limited: seven from Greenland, with only one providing an undisturbed record of a part of the last interglacial period, and a dozen from Antarctica, with the longest record covering the last 800 000 yr. This article aims to summarize this successful adventure initiated by a few pioneers and their teams and to review key scientific results by focusing on climate (in particular water isotopes) and climate-related (e.g. greenhouse gases) reconstructions. Future research is well taken into account by the four projects defined by IPICS. However, it remains a challenge to get an intact record of the Last Interglacial in Greenland and to extend the Antarctic record through the mid-Pleistocene transition, if possible back to 1.5 Ma.

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Reconstruction of the last interglacial period from the NEEM ice core

PAGES news ◽

10.22498/pages.21.1.22 ◽

2013 ◽

Vol 21 (1) ◽

pp. 22-23

Author(s):

Dorthe Dahl-Jensen ◽

P Gogineni ◽

JWC White

Keyword(s):

Ice Core ◽

Interglacial Period ◽

Last Interglacial ◽

Last Interglacial Period

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How warm was Greenland during the last interglacial period?

10.5194/cp-2016-28 ◽

2016 ◽

Cited By ~ 4

Author(s):

Amaelle Landais ◽

Valérie Masson-Delmotte ◽

Emilie Capron ◽

Petra M. Langebroek ◽

Pepijn Bakker ◽

...

Keyword(s):

Accumulation Rate ◽

Ice Core ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Water Isotopes ◽

Interglacial Period ◽

Last Interglacial ◽

Surface Warming ◽

Last Interglacial Period ◽

Industrial Level

Abstract. The last interglacial period (LIG, ~ 129–116 thousand years ago) provides the most recent case study for multi-millennial polar warming above pre-industrial level and a respective response of the Greenland and Antarctic ice sheets to this warming, as well as a test bed for climate and ice sheet models. Past changes in Greenland ice sheet thickness and surface temperature during this period were recently derived from the NEEM ice core records, North-West Greenland. The NEEM paradox has emerged from an estimated large local warming above pre-industrial level (7.5 ± 1.8 °C at the deposition site 126 ka ago without correction for any overall ice sheet altitude changes between the LIG and pre-industrial) based on water isotopes, together with limited local ice thinning, suggesting more resilience of the real Greenland ice sheet than shown in some ice sheet models. Here, we provide an independent assessment of the average LIG Greenland surface warming using ice core air isotopic composition (δ15N) and relationships between accumulation rate and temperature. The LIG surface temperature at the upstream NEEM deposition site without ice sheet altitude correction is estimated to be warmer by &plus;7 to &plus;11 °C (&plus;8 °C being the most likely estimate according to constraints on past accumulation rate) compared to the pre-industrial period. This temperature estimate is consistent with the 7.5 ± 1.8 °C warming initially determined from NEEM water isotopes. Moreover, we show that under such warm temperatures, melting of snow probably led to a significant firn shrinking by ~ 15 m. Climate simulations performed with present day ice sheet topography lead to much smaller warming but larger amplitudes (up to 5 °C) can be obtained from changes in sea ice extent and ice sheet topography. Still, ice sheet simulations forced by 5 °C surface warming lead to large ice sheet decay that are not compatible with existing data. Our new, independent temperature constrain therefore reinforces the NEEM paradox.

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The Taylor Dome Antarctic 18O Record and Globally Synchronous Changes in Climate

Quaternary Research ◽

10.1006/qres.2001.2276 ◽

2001 ◽

Vol 56 (3) ◽

pp. 289-298 ◽

Cited By ~ 71

Author(s):

Pieter M. Grootes ◽

Eric J. Steig ◽

Minze Stuiver ◽

Edwin D. Waddington ◽

David L. Morse ◽

...

Keyword(s):

Thermohaline Circulation ◽

Ice Core ◽

Interglacial Period ◽

Last Interglacial ◽

Conflicting Evidence ◽

Last Interglacial Period ◽

Stage 4 ◽

Marine Influence ◽

Atlantic Thermohaline Circulation ◽

The Last Glacial

AbstractThe 18O/16O profile of a 554-m long ice core through Taylor Dome, Antarctica, shows the climate variability of the last glacial–interglacial cycle in detail and extends at least another full cycle. Taylor Dome shares the main features of the Vostok record, including the early climatic optimum with later cool phase of the last interglacial period in Antarctica. Taylor Dome δ18O fluctuations are more abrupt and larger than those at Vostok and Byrd Station, although still less pronounced than those of the Greenland GISP2 and GRIP records. The influence of the Atlantic thermohaline circulation on regional ocean heat transport explains the partly “North Atlantic” character of this Antarctic record. Under full glacial climate (marine isotope stage 4, late stage 3, and stage 2), this marine influence diminished and Taylor Dome became more like Vostok. Varying degrees of marine influence produce climate heterogeneity within Antarctica, which may account for conflicting evidence regarding the relative phasing of Northern and Southern Hemisphere climate change.

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Climate instability during the last interglacial period recorded in the GRIP ice core

Nature ◽

10.1038/364203a0 ◽

1993 ◽

Vol 364 (6434) ◽

pp. 203-207 ◽

Cited By ~ 581

Author(s):

Keyword(s):

Ice Core ◽

Interglacial Period ◽

Last Interglacial ◽

Last Interglacial Period

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A brief history of ice core science over the last 50 yr

Climate of the Past Discussions ◽

10.5194/cpd-9-3711-2013 ◽

2013 ◽

Vol 9 (4) ◽

pp. 3711-3767 ◽

Cited By ~ 2

Author(s):

J. Jouzel

Keyword(s):

Environmental Changes ◽

Ice Core ◽

Ice Cores ◽

Future Research ◽

Interglacial Period ◽

Last Interglacial ◽

Last Interglacial Period ◽

History Of ◽

Scientific Results ◽

The Antarctic

Abstract. For about 50 yr, ice cores have provided a wealth of information about past climatic and environmental changes. Ice cores from Greenland, Antarctica and other glaciers, now emcompass a variety of timescales. However, the longer time scales (e.g. at least back to the Last Glacial period) are covered by deep ice cores the number of which is still very limited, seven from Greenland, with only one providing an undisturbed record of a part of the Last Interglacial Period, and a dozen from Antarctica with the longest record covering the last 800 000 yr. This article aims to summarize this successful adventure initiated by a few pioneers and their teams and to review key scientific results in focusing on climate (in particular water isotopes) and climate related (e.g. greenhouse gases) reconstructions. Future research is well taken into account by the four projects defined by IPICS. However it remains a challenge to get an intact record of the Last Interglacial in Greenland and to extend the Antarctic record through the mid-Pleistocene transition, if possible back to 1.5 Myr.

Download Full-text