Abstract
The East Asian summer monsoon (EASM) is important for bringing rainfall to large areas of China. Historically, variations in the EASM have had major impacts including flooding and drought. The authors present an analysis of the impact of anthropogenic climate change on EASM rainfall in eastern China using a newly updated attribution system. The results suggest that anthropogenic climate change has led to an overall decrease in total monsoon rainfall over the past 65 years and an increased number of dry days. However, the model also predicts that anthropogenic forcings have caused the most extreme heavy rainfall events to become shorter in duration and more intense. With the potential for future changes in aerosol and greenhouse gas emissions, historical trends in monsoon rainfall may not be indicative of future changes, although extreme rainfall is projected to increase over East Asia with continued warming in the region.
Highlights
The East Asian summer monsoon (EASM) brings much-needed water for agriculture to most of eastern China
The rainfall total on individual days in the tenth decile is likely to be greater in the ALL world—while this change is not statistically significant for the majority of individual grid cells, it is statistically significant when we average over larger areas
Under anthropogenic forcings the model predicts that there is, on average, a decrease in the total monsoon rainfall, an increase in the number of dry days, an increase in the total rain that falls in the first decile of daily totals, and a decrease in the total rainfall in the tenth decile of daily total rain
Summary
The East Asian summer monsoon (EASM) brings much-needed water for agriculture to most of eastern China. In this study we examine changes in the East Asian summer monsoon rainfall over China using an ensemble of simulations from an atmosphere-only climate model representing present-day conditions with anthropogenic influences and comparing these to an ensemble representing conditions without anthropogenic influences. Han and Zhou (2012) compare the APHRODITE dataset to daily rainfall records from 559 rain gauges spread over China They find that the APHRODITE data show very similar rainfall amounts for mean variables, such as seasonal total, and accurately characterize the progression of the seasonal rainband. A large difference is found between the station and APHRODITE data for spatial patterns of trends in intense rainfall, and the APHRODITE data underestimate trends in the recent northern drought– southern flood pattern compared to station data With these limitations in mind, we use the APHRODITE data for model verification of seasonal rainfall characteristics and focus on the model output for examining trends in rainfall and changes in extreme rainfall characteristics.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
