How to treat the rainy weather phenomenon this year?

It is no accident that there was too much rain this summer, especially the increase in extreme rainfall. This phenomenon is closely related to climate change. According to the statistics of China Meteorological Bureau, the national average precipitation in June this year reached 1 10.9ml, which was more than the same period last year 12%. This data seems to have broken through the historical record, which has added a lot of difficulties to the flood control work this year. According to the statistics of the Emergency Management Department, as of July 3rd this year, 26 provinces (autonomous regions and municipalities) such as Guizhou, Sichuan and Quanta have been seriously affected by floods this year, with * * *19.38 million people affected, 12 1 person dead and missing, and economic losses reaching 4/kloc-0.

So what is the main cause of extreme climate?

First of all, research shows that climate change caused by human activities increases the probability of similar extreme precipitation events.

From April to May of 20 18, severe drought occurred in Guangdong, Fujian and Guizhou. The precipitation in southern areas such as Guangdong and Fujian is 40% less than the annual average 195 1-20 18, and the surface temperature is 2.8 degrees Celsius higher. The analysis results show that the climate change caused by human activities increases the possibility of such events by nearly 17 times.

? Second, global warming increases the probability of extreme weather.

Since 198 1 year, the global annual average temperature has increased at a rate of 0. 18℃ every decade. 20 19 is the second hottest year in the past 140 years, and the global land and ocean surface temperature is 0.95℃ higher than the average. The change of average surface temperature and variability directly affects the change of extreme temperature, which intensifies the water cycle process to some extent and increases the frequency and intensity of disasters such as high temperature, drought, rainstorm and flood in some areas. When the SST in the South China Sea is unusually warm in summer, southerly winds appear in the lower layer of the South China Sea, and an unusually large amount of water vapor is transported to the south of China, floods are prone to occur in the middle and lower reaches of the Yangtze River in China.

Third, the impact of population density on extreme weather, especially in urban areas, because of the high population density, the probability of human activities affecting extreme weather increases.

In the process of urbanization, the natural surface is transformed into a typical urban underlying surface dominated by cement, asphalt and masonry, and the surface albedo, evapotranspiration, energy and water cycle change, resulting in urban heat island and rain island effect, which increases the possibility of high-intensity rainstorm in cities. Especially in large-scale cities and large-scale built-up areas, the balance of atmospheric moisture and energy budget is affected, convection activities are strengthened, and the formation of extreme precipitation is promoted.