关于长江数次洪灾成因的思考

长江流域近年来发生了数次特大洪灾，危害甚巨，我们虽已战胜了这一场灾害，然而，我们对洪水成因的思考却显得更加重要了，如何让长江不再发生类似灾害，从生态学角度寻找洪灾成因并提出解决措施。     

Monitoring of the 2011 spring low ozone events in the Arctic region

Data from FY-3B SBUS and NOAA SBUV/2 were used to monitor ozone levels in the Arctic region from March 1 to April 5, 2011. Results revealed a significant ozone depletion in the area, with total ozone levels between 200–250 DU. The ozone levels recorded were 100–200 DU below normal, and in some parts the levels were as low as 200 DU, indicating a mini ozone-hole. During the sampling period, the ozone depletion area underwent identifiable expansion and detraction, a rotation around the North Pole from the west to the east, and a longitudinal movement from the Pole, spreading to the mid latitudes. The effects of these rare low ozone events were not only felt in the Arctic, but also extended to densely populated areas between Europe and the middle of Russia. In this region, rapidly increasing levels of ultraviolet radiation were detected at the Earth’s surface. Given the significant risk that this poses to both the environment and people’s health, this occurrence has significant global implications.