1. Using Ice Cores and Gaussian Process Emulation to Recover Changes in the Greenland Ice Sheet During the Last Interglacial
- Author
-
Louise C. Sime, Jochen Voss, Emilie Capron, Dario Domingo, and Irene Malmierca-Vallet
- Subjects
010504 meteorology & atmospheric sciences ,Greenland Ice Sheet ,Greenland ice sheet ,SEA-LEVEL RISE ,Last Interglacial ,01 natural sciences ,Physics::Geophysics ,symbols.namesake ,Ice core ,Range (statistics) ,Gaussian process emulation ,GLACIAL MAXIMUM ,Gaussian process ,Gaussian process emulator ,Physics::Atmospheric and Oceanic Physics ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Remote sensing ,COUPLED MODEL ,CHRONOLOGY AICC2012 ,Probabilistic logic ,CONSTRAINTS ,ANTARCTIC ICE ,SIMULATIONS ,OXYGEN-ISOTOPE ,CLIMATE ,Geophysics ,13. Climate action ,AIR CONTENT ,Interglacial ,symbols ,Climate model ,Geology - Abstract
The shape and extent of the Greenland Ice Sheet (GIS) during the Last Interglacial (LIG) is a matter of controversy, with different studies proposing a wide range of reconstructions. Here, for the first time, we combine stable water isotopic information from ice cores with isotope-enabled climate model outputs to investigate the problem. Exploring the space of possible ice sheet geometries by simulation is prohibitively expensive. We address this problem by using a Gaussian process emulator as a statistical surrogate of the full climate model. The emulator is calibrated using the results of a small number of carefully chosen simulations and then permits fast, probabilistic predictions of the simulator outputs at untried inputs. The inputs are GIS morphologies, parameterized through a dimension-reduction technique adapted to the spherical geometry of the setting. Based on the emulator predictions, the characteristics of morphologies compatible with the available ice core measurements are explored, leading to a reduction in uncertainty on the LIG GIS morphology. Moreover, a scenario-based approach allows to assess the gains in uncertainty reduction which would result from the availability of better dated LIG measurements in Greenland ice cores.
- Published
- 2020