摘 要:运用多种方法分析了苏北地区1960~2009年间旱涝灾害的时空演变特征。结果表明:(1)苏北地区平均降水量为967mm,年际波动较大,但呈增加趋势。春、秋季表现为递减趋势,夏、冬季为增加趋势。(2)各时间尺度SPI对降水敏感性各异,但均能准确监测旱涝事件。年和季节SPI递增(减)趋势与降水量变化相同。(3)各时间尺度SPI周期为2~8个月左右。年、夏季存在3次周期变化,春秋季次之,冬季仅在20世纪60年代出现2~3a的短周期。(4)年SPI变率呈先升后降变化,季节SPI变率中秋季变幅最小、春季最大。淮安的年、季节SPI变率与苏北地区最为贴近。(5)苏北各地以洪涝为主,且2000年后有频发趋势。各地年、季节旱涝状况不一,但淮安的旱涝灾害最为频繁,需重点关注。58656
毕业论文关键词:降水,标准化降水指数,旱涝灾害,时空特征,苏北地区
Abstract: The temporal and spatial characteristics of flood and drought disasters during 1960-2009 in the north of Jiangsu Province are analyzed using many methods. Results show that: (1) The annual average rainfall is 967 mm in the north of Jiangsu, which has large fluctuation amplitude with a trend of increase. Spring and autumn’s rainfall is increasing, but summer and winter’s is decreasing. (2) Flood and drought can be monitored by all multi-scale SPI, even which has different sensitive to the precipitation. The annual and seasonal SPI have the same trend of increase and decrease. (3) A period at about 2-8 mouths can be checked for multi-scale SPI change. There are 3 times’ period changes in annual and summer SPI, and the winter only has a period at about 2-3 years, happened in 1960s. (4) The variation in annual is lowered after the rise. In season, autumn has the large change amplitude though spring has the little change. Variation in Huai’an City is the most suitable to the north of Jiangsu Province. (5) Flood is a primary disaster in this area, which will be more frequent since 2000. Huai’an City should be focused on for its serious flood and drought disasters.
Keywords: precipitation, Standardized Precipitation Index, flood and drought disasters, temporal and spatial characteristics, the north of Jiangsu Province
1 前言 4
2 数据与方法 4
2.1 区域概述 4
2.2 数据来源 5
2.3 研究方法 6
3 结果与分析 9
3.1 降水量的特征分析 9
3.2 旱涝的时间变化分析 10
3.3 旱涝的周期变化分析 14
3.4 旱涝的变率变化分析 16
3.5 旱涝的空间变化分析 20
结 论 23
参考文献 24
致 谢 27
1 前言
所谓干旱,是指某区域内由于一段时间降水量显著减少而引起水分短缺的现象[1,2]。而洪涝则与干旱相反,是一种因降水显著增强致使洪水泛滥、淹没周边地物的自然灾害[3]。由此可见,旱涝事件是水分分布与水文循环的极端情形,因而降水是影响旱涝的主要因素[4,5]。旱涝灾害的发生不仅对农业生产和人身安全构成威胁,更会对生态环境稳定和经济社会发展有着重要影响,故旱涝灾害引起了世界各国的广泛关注[2,3,6,7]。