Source: Global Change and Earth System Science Institute
The Northwest Pacific Ocean is the region with the highest frequency and highest intensity of typhoon explosions in the world. This year's frequent typhoon incidents have received wide attention. The size of a typhoon disaster usually depends on two aspects, one is the intensity of the typhoon and the other is the size of the typhoon. Compared with strong typhoons, disasters caused by large-scale typhoons often cause more serious loss of life and property due to the wide coverage. So what are the factors that determine the size of the typhoon? Asia, which is adjacent to the western Pacific, has been seriously polluted in recent years. Is there a relationship with the typhoon?
Professor Zhao Chuanfeng from the Global Institute of Beijing Normal University used satellite observation and meteorological reanalysis data to analyze the impact of human pollution on typhoons in the Northwest Pacific. It was found that aerosols can promote the expansion of typhoon precipitation disasters at the expense of a certain typhoon maximum energy. The results were published in the Journal of the American Geophysical Society, Geophysical Research Letters, entitled "Enlarging Rainfall Area of Tropical Cyclones by Atmospheric Aerosols" (https://agupubs.onlinelibrary.wiley.com/doi/pdf/ 10.1029/2018GL079427). Researcher Yuan Wang, a collaborator at the California Institute of Technology, used model research in 2014 to find that aerosols emitted by Asian models in the model can affect the typhoon precipitation area in the Northwest Pacific, and there has been a lack of observation-based evidence. Professor Zhao Chuanfeng and others in this work based on satellite observation (MODIS) aerosol optical thickness (AOD), satellite observation typhoon path and TRMM precipitation inversion data, combined with re-analysis data (MERRA-2) aerosol optical thickness, for the first time, the relationship between aerosol and typhoon precipitation area was revealed by observation using statistical methods. The study found that aerosols have a very significant impact on the size of the typhoon precipitation area. On average, for every 0.1 increase in aerosols in the Pacific Northwest, the size (radius) of typhoon precipitation increases by 9-20 km. This finding means that the increase in anthropogenic aerosol pollution not only increases the intensity of precipitation, but also leads to a larger area of typhoon precipitation, resulting in more serious disasters.
This research is subject to the National Key Research and Development Program “Significant Natural Disaster Monitoring, Early Warning and Prevention” project “Study on Interaction Mechanism of Aerosol Convective Cloud Precipitation and Application of Beijing-Tianjin-Hebei Regional Model” (2017YFC1501403), National Natural Science Foundation of China (41575143), The Youth 1000-person plan, the State Key Laboratory of Surface Process and Resource Ecology, and the basic research business of the Central University are jointly funded.