Water-stable isotopes in the LMDZ4 general circulation model: Model evaluation for present-day and past climates and applications to climatic interpretations of tropical isotopic records

摘要: We present simulations of water-stable isotopes from the LMDZ general circulation model (the LMDZ-iso GCM) and evaluate them at different time scales (synoptic to interannual). reproduces reasonably well spatial seasonal variations both delta O-18 deuterium excess. When nudged with reanalyses, is able capture synoptic variability in winter a midlatitude station, interannual mid high latitudes strongly improved. The degree equilibration between vapor precipitation sensitive kinetic effects during rain reevaporation, calling for more synchronous measurements. then two past climates: Last Glacial Maximum (21 ka) Mid-Holocene (6 ka). A particularity compared other isotopic GCMs that it simulates lower d excess LGM over most high-latitude regions, consistent observations. Finally, we use explore relationship tropics, discuss its paleoclimatic implications. show imprint uniform temperature changes on tropical weak. Large regional can, however, be associated dynamical precipitation. Using as test bed reconstructing through local records, can reconstructed qualitatively but not quantitatively. Over continents, nonlocal make reconstruction even less accurate.