Last glacial maximum climate over China from PMIP simulations
article i nfo Using the results of 25 climate models under the framework of the Paleoclimate Modelling Intercomparison Project(PMIP)and available proxydata,thisstudyexaminesthe regionalclimate ofChina during the LastGlacial Maximum (LGM: 21,000 years ago). Compared to the baseline climate, results show that annual surface temperature decreasedby2.00°-7.00 °C inChina during thatperiod,withanaverage of 4.46 °C, forthe ensemble mean of all models. Annual precipitation and evaporation during the LGM were 5-40% less than the baseline values, with an average reduction of 20% (0.60 mm/day) and a reduction of 21% (0.41 mm/day) at the national scale, based on results from 15 out of the 25 models. These models were selected for their ability to simulate the modern precipitation climatology and for the availability of suitable evaporation data. Both the geographical distribution and magnitude of changes in surface temperature, precipitation, and evaporation during the LGM varied with the seasons and with the models, particularly at the sub-regional scale. Model-data comparisons revealed that the 25 models successfully reproduced the surface cooling trend during the LGM, but they failed to reproduce its magnitude in all four regions of comparison, particularly in the Hexi Corridor and in North and NortheastChina.Thesimulationswithcomputedseasurface temperatures(SSTs)wereinbetteragreementwith proxy estimates of surface temperature than those with prescribed SSTs. On the other hand, large-scale LGM- minus-baseline anomalies in annual precipitation minus evaporation agreed well, in a qualitative manner, with lake status-based reconstructions of changes in annual water budgets in East China and the region of 35°-42°N, 74°-97°E. On the eastern Qinghai-Tibetan Plateau, drier climates from the 15 models agreed with pollen-based reconstructions. For most parts of West China excluding the Qinghai-Tibetan Plateau, the simulations with computed (prescribed) SSTs are consistent (inconsistent) with reconstructed moister conditions.