摘要：South Asian monsoons were analyzed within the context of increasing emissions of black carbon (BC) aerosols using a global atmospheric general circulation model. The BC aerosols were allowed to increase only over the south Asian domain to analyze the impacts of regional black carbon over the climatological patterns of monsoons. The black carbon significantly absorbed the incoming short wave radiation in the atmosphere, a result that is consistent with previous studies. Pre-monsoon (March-April-May) rainfall showed positive anomalies, particularly for some coastal regions of India. The summer (June-July-August) rainfall anomalies were negative over the northern Himalayas, Myanmar, southern China, and most of the regions below 20°N due to the decrease in temperature gradients induced by the absorption of radiation by BC aerosols. The vertical wind speed anomalies indicated that these regions experienced less convection, which reduces the precipitation efficiency of the monsoon system in South Asia.
关键词：South Asia; monsoon; BC aerosols; convection; temperature gradients
