Simulations Of Aerosol And Greenhouse Gas Influences On The East Asian Winter Monsoon

In the context of climate change,due to the influence of human activities,the increase of aerosols and greenhouse gases in the atmosphere,both affect the atmosphere's radiation balance,cloud and precipitation,thus affecting the thermodynamic differences of the underlying surface.Taking East Asia as an example,the influence of aerosols and greenhouse gases on the thermal differences between the Asian continent and the Indian Ocean Pacific will change the dynamic conditions for the formation of the East Asian winter monsoon,and the East Asian winter monsoon will affect the climate of East Asian countries.This paper uses NCEP/NCAR reanalysis data from 2001 to 2010 to test the ability of the atmospheric module CAM5 in the global climate system model CESM to simulate the East Asian monsoon of winter monsoon.The results show that the model can reproduce the main features of the East Asian winter monsoon.Through sensitive experiments,the mechanism of aerosols and greenhouse gases affecting the East Asian winter monsoon was explored.The effects of non-uniform heating caused by aerosols and greenhouse gases on the divergence and non-divergence wind intensity were analyzed and discussed.East Asian winter monsoon was discussed.The reason for the weakening has deepened the understanding of the causes of the weakening of the East Asian winter monsoon and has important implications for the study of aerosols,greenhouse gases,and the East Asian winter monsoon.The main conclusions are as follows:(1)The increase in aerosols and greenhouse gases has weakened the winter monsoon in the eastern part of China,the Korean peninsula and the Japanese islands.The aerosols weakened the northerly winds in East Asia,and the greenhouse gases weakened the westerlies and the north winds of East Asia.Under the combined effect of the two,the north wind weakened significantly.At the same time,precipitation changes in the southeast of China are reduced under the influence of aerosols and are also reduced under the influence of greenhouse gases.Precipitation is related to changes in heat sources,greenhouse gases warm the surface,and aerosols cool the surface.(2)Increases in aerosols and greenhouse gases have changed the distribution of atmospheric heat sources,resulting in weakened heat sources or enhanced heat transfer in some areas.Heating in the warm area and cooling in the cold area will produce full potential energy,and vice versa.The increase of aerosols and greenhouse gases caused the heat sources in the southeastern China(warm areas)to weaken and heat sinks to increase;the heat sinks in northeast China(cold areas)weakened and heat sources strengthened.Both make the potential energy in these areas decrease and consume more.(3)Both test A and test B confirm that the change of atmospheric heat source is mainly caused by the change of latent heat of condensation,and the change of latent heat of condensation produced by the large-scale process plays a major role.Compared to aerosols,greenhouse gases have a greater impact on the latent heat of condensation in large-scale processes and have a greater impact on heat sources.(4)Changes in the atmospheric heat source change the thermal structure in the monsoon region and change the potential energy and kinetic energy as well as the conversion between them.Both aerosols and greenhouse gases have increased the conversion of divergent wind kinetic energy to full-position energy near the southeastern part of China,the Korean Peninsula,and the Japanese islands,resulting in weakened divergent winds.At the same time,under the influence of both,the conversion of divergent winds without divergent winds in most parts of East Asia weakened,resulting in the weakening of non-divergent winds.Consistent with the previous wind field difference plot,it was proved that the non-divergent wind was weakened.Eventually the East Asian monsoon weakened...