Sensitivity studies on the impacts of Tibetan Plateau snowpack pollution on the Asian hydrological cycle and monsoon climate

摘要: Abstract. The Tibetan Plateau (TP) has long been identified to be critical in regulating the Asian monsoon climate and hydrological cycle. In this modeling study a series of numerical experiments with global model are designed simulate radiative effect black carbon (BC) dust snow, assess relative impacts anthropogenic CO2 carbonaceous particles atmosphere snow on snowpack over TP subsequent Simulations results show large BC content TP, especially southern slope. Because high aerosol incident solar radiation low latitude elevation, exhibits largest surface flux changes induced by aerosols (e.g. BC, Dust) compared any other snow-covered regions world. Simulation that aerosol-induced albedo perturbations generate 5–25 W m−2 during spring, maximum April or May. BC-in-snow increases air temperature around 1.0 °C averaged reduces spring more than pre-industrial present increase atmosphere. As result, runoff late winter early but decreases summer (i.e. trend toward earlier melt dates). snowmelt efficacy, defined as reduction per unit degree warming forcing agent, is 1–4 times larger for April–July, indicating efficiently accelerates because increased net reduced melts due air. also influences South (SAM) East (EAM) through its dynamical thermal forcing. boreal transported southwesterly, causing some reach higher altitude deposit TP. While Organic Matter (OM) directly absorb sunlight warm air, darkened polluted absorbs skin temperature, which warms above sensible heat flux. Both effects enhance upward motion spur deep convection along pre-monsoon season, resulting onset SAM moisture, cloudiness convective precipitation northern India. significant impact EAM July Contributed both associated latent soil moisture memory, role pump elevated from land-sea contrast strengthen EAM. China become wetter, central Yangtze River Basin) becomes drier – near-zonal anomaly pattern consistent dominant mode variability Asia. impurity reported likely represent upper limits remarkably overestimated excessive precipitation. Improving simulation will important improved estimates pollution future work.