Open AccessSimulating climate and stable water isotopes during the L ast I nterglacial using a coupled climate‐isotope model
Author(s) -
Gierz Paul,
Werner Martin,
Lohmann Gerrit
Publication year - 2017
Publication title -
journal of advances in modeling earth systems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.03
H-Index - 58
ISSN - 1942-2466
DOI - 10.1002/2017ms001056
Subject(s) - interglacial , climatology , paleoclimatology , environmental science , climate model , proxy (statistics) , climate change , climate state , forcing (mathematics) , isotope , ice core , atmospheric sciences , stable isotope ratio , climate system , global warming , glacial period , geology , effects of global warming , oceanography , geomorphology , machine learning , computer science , physics , quantum mechanics
Understanding the dynamics of warm climate states has gained increasing importance in the face of anthropogenic climate change, and while it is possible to simulate warm interglacial climates, these simulated results cannot be evaluated without the aid of geochemical proxies. One such proxy is δ 18 O, which allows for inference about both a climate state's hydrology and temperature. We utilize a stable water isotope equipped climate model to simulate three stages during the Last Interglacial (LIG), corresponding to 130, 125, and 120 kyr before present, using forcings for orbital configuration as well as greenhouse gases. We discover heterogeneous responses in the mean δ 18 O signal to the climate forcing, with large areas of depletion in the LIG δ 18 O signal over the tropical Atlantic, the Sahel, and the Indian subcontinent, and with enrichment over the Pacific and Arctic Oceans. While we find that the climatology mean relationship between δ 18 O and temperature remains stable during the LIG, we also discover that this relationship is not spatially consistent. Our results suggest that great care must be taken when comparing δ 18 O records of different paleoclimate archives with the results of climate models as both the qualitative and quantitative interpretation of δ 18 O variations as a proxy for past temperature changes may be problematic due to the complexity of the signals.