报告题目：Dust activities and their associated climate variability in Syria and the United States

　　报 告 人：Dr. Bing Pu (濮冰)

　　单  位：Princeton University, NOAA Geophysical Fluid Dynamics Laboratory

　　时  间：2017年4月10日上午9:30

　　地  点：大气所40号楼319会议室

　　摘  要：In this talk I will discuss 1) the springtime dust activity in Syria controlled by a remote forcing, the Pacific decadal oscillation (PDO), and 2) how droughts may intensify dust activity in the United States in the late 21st century based on observations and climate model output.

　　Dust aerosols play an important role in the climate system by modulating Earth’s radiation balance and hydrological cycle as well as ocean biogeochemical cycle. Strong dust storms also have severe social and health impacts. The 2015 severe dust storm in Syria raised concerns as whether dust activities will increase in the region. First step toward answering this question is to understand the dust activities driven by the natural climate variability. Here we used MODIS Deep Blue aerosol products and GFDL AM3 model to examine the influence of the PDO on Syrian dust activities in spring.

　　Climate models projected rising drought risks over the southwestern and central U.S. in the 21st century due to increasing greenhouse gases. The predicted drier regions largely overlay the major dust sources in the United States. However, whether dust activity in U.S. will increase in the future is not clear due to large uncertainties of dust modeling. This study found that changes of dust activity in the U.S. are largely associated with the variations of precipitation, bareness, and surface wind speed.Using satelliteobservation and multi-model output we project that under the Representative Concentration Pathways 8.5 scenario dust activitywill increase in the southern Great Plains from spring to fallin the late half of the 21stcentury but will decrease in the northern Great Plains in spring.