On the basis of large amount of historical and measured data, this paper analyzed the regional, periodic, frequency, continuing, and response characteristics of droughts and floods in Zhejiang and proposed the concept...On the basis of large amount of historical and measured data, this paper analyzed the regional, periodic, frequency, continuing, and response characteristics of droughts and floods in Zhejiang and proposed the conception of ratio of peak runoff. Main characteristics of droughts and floods in Zhejiang are as follows: 1) The western Zhejiang region is plum rain major control area, and the eastern coastal region of Zhejiang is typhoon major control area. 2) Within a long period in the future, Zhejiang will be in the long period that features droughts. 3) In Zhejiang the 17th century was frequent drought and flood period, the 16th, 19th, and 20th centuries were normal periods, while the 18th century was spasmodic drought and flood period. 4) The severe and medium floods in Zhejiang were all centered around the M-or m-year of the 11-year sunspot activity period. 5) There are biggish years of annual runoff occurred in E1 Nifio year (E) or the following year (E+1) in Zhejiang. The near future evolution trend of droughts and floods in Zhejiang is as follows: 1) Within a relatively long period in the future, Zhejiang Province will be in the long period of mostly drought years. 2) Between 1999 and 2009 this area will feature drought years mainly, while the period of 2010-2020 will feature flood years mostly. 3) Zhejiang has a good response to the sunspot activities, and the years around 2009, 2015, and 2020 must be given due attention, especially around 2020 there might be an extremely severe flood year in Zhejiang. 4) Floods in Zhejiang have good response to El Nifio events, in El Nifio year or the following year much attention must be paid to. And 5) In the future, the first, second, and third severe typhoon years in Zhejiang will be 2009. 2012. and 2015. resnectivelv.展开更多
A socio-economic data set on China's historical flood losses for the period 1984--2012 was compiled to analyze the exposed population, economy, and crop area as well as the vulnerabilities of the population and econo...A socio-economic data set on China's historical flood losses for the period 1984--2012 was compiled to analyze the exposed population, economy, and crop area as well as the vulnerabilities of the population and economy to floods. The results revealed that the exposed population was approximately 126 persons km-2 per year when taking China as a whole; in terms of the economy, potential losses due to floods were estimated to be approximately 1.49 million C/W4 km 2 and the crop area exposed to floods covered 153 million hm2 per year. China's total exposure to floods significantly increased over the analysis period. The areas that showed the higher exposure were mainly located along the east coast. The population's vulnerability to floods showed a significantly increasing trend, however, the economic vulnerability showed a decreasing trend. The populations and economies that were most vulnerable to floods were in Hunan, Anhui, Chongqing, Jiangxi, and Hubei provinces. The municipalities of Shanghai, Beijing, and Tianjin showed the lowest vulnerabilities to floods.展开更多
基金Under the auspices of Zhejiang Provincial ScienceTechnology Foundation of China(No.2006C23066)
文摘On the basis of large amount of historical and measured data, this paper analyzed the regional, periodic, frequency, continuing, and response characteristics of droughts and floods in Zhejiang and proposed the conception of ratio of peak runoff. Main characteristics of droughts and floods in Zhejiang are as follows: 1) The western Zhejiang region is plum rain major control area, and the eastern coastal region of Zhejiang is typhoon major control area. 2) Within a long period in the future, Zhejiang will be in the long period that features droughts. 3) In Zhejiang the 17th century was frequent drought and flood period, the 16th, 19th, and 20th centuries were normal periods, while the 18th century was spasmodic drought and flood period. 4) The severe and medium floods in Zhejiang were all centered around the M-or m-year of the 11-year sunspot activity period. 5) There are biggish years of annual runoff occurred in E1 Nifio year (E) or the following year (E+1) in Zhejiang. The near future evolution trend of droughts and floods in Zhejiang is as follows: 1) Within a relatively long period in the future, Zhejiang Province will be in the long period of mostly drought years. 2) Between 1999 and 2009 this area will feature drought years mainly, while the period of 2010-2020 will feature flood years mostly. 3) Zhejiang has a good response to the sunspot activities, and the years around 2009, 2015, and 2020 must be given due attention, especially around 2020 there might be an extremely severe flood year in Zhejiang. 4) Floods in Zhejiang have good response to El Nifio events, in El Nifio year or the following year much attention must be paid to. And 5) In the future, the first, second, and third severe typhoon years in Zhejiang will be 2009. 2012. and 2015. resnectivelv.
基金supported by the National Basic Research Program of China(No.2012CB955903)
文摘A socio-economic data set on China's historical flood losses for the period 1984--2012 was compiled to analyze the exposed population, economy, and crop area as well as the vulnerabilities of the population and economy to floods. The results revealed that the exposed population was approximately 126 persons km-2 per year when taking China as a whole; in terms of the economy, potential losses due to floods were estimated to be approximately 1.49 million C/W4 km 2 and the crop area exposed to floods covered 153 million hm2 per year. China's total exposure to floods significantly increased over the analysis period. The areas that showed the higher exposure were mainly located along the east coast. The population's vulnerability to floods showed a significantly increasing trend, however, the economic vulnerability showed a decreasing trend. The populations and economies that were most vulnerable to floods were in Hunan, Anhui, Chongqing, Jiangxi, and Hubei provinces. The municipalities of Shanghai, Beijing, and Tianjin showed the lowest vulnerabilities to floods.