基于GCM的蒙古高原降水稳定同位素模拟

his study used five atmospheric circulation models (GCM) from SWING2 and the second stable water isotope comparison group, to analyze the atmospheric water line equations of precipitation isotopes, spatial and temporal variations, and temperature relationships in the Mongolian Plateau. They were compared with the data from the Global Network for Isotope Observation and Information on Precipitation (GNIP), to provide detailed precipitation isotope information for the Mongolian Plateau, which lacks measurement stations. The results show that the local atmospheric water equation D=7.78318O+3.011 simulated by LMDZ (ECMWF) was closer to the measured values; the 18O and D simulated by the five GCM models had significant seasonal variations, and the best simulation of their average monthly values were LMDZ (free) and LMDZ (ECMWF); and the results are based on the latitudinal effect. Only the CAM2 (free), LMDZ (ECMWF), and MIROC (free) models demon strated the latitudinal effect in the Mongolian Plateau. In terms of longitude, the LMDZ (ECMWF) and isoGSM(NCEP) models showed that the 18O values during precipitation in the western section of the region (87~107E) were higher than those in the eastern section (107~127E). Except for LMDZ (free), which demonstrated a weak temperature effect, others showed a robust impact. The LMDZ (ECMWF) model simulated the highest correlation coefficient between 18O and temperature during precipitation in the two areas, with the strongest temperature effect.