基于帕默尔干旱指数的中国春季区域干旱特征比较研究

Compare research of the regional arid characteristic base on Palmer drought severity index in spring over China

利用全国515个站(1957-2000年)气象资料,修正计算帕默尔干旱指数(Palmer drought severity index),进行干旱区划和研究春季区域演变特征。结果表明:中国干旱变化全区一致性程度低,干旱演变的区域差别大,存在着以内蒙古高原、南岭、华北北部及长白山脉、长江中下游、黄土高原、黄淮地区、天山北部、东北平原、河西走廊、云贵高原、塔里木盆地、青藏高原等为代表的12个干旱特征区。内蒙古高原区、华北北部及长白山脉区、黄土高原区、天山北部区域、东北平原区、河西走廊及其沙漠戈壁区春季干旱指数趋势变化呈下降趋势。南岭区、长江中下游区、黄淮区域、云贵高原区、塔里木盆地区、青藏高原区春季干旱指数趋势变化呈上升趋势。中国春季干旱指数大多存在5～8年的短周期年际周期变化,12～13年、15～16年的长周年际周期变化存在于部分区域,个别区域还存在20年长周期年际周期变化。中国干旱的区域特征差别显著。

By modifying Palmer drought severity index base on the 515 stations meteorological data from 1957 to 2000 over China, regional arid evolution characteristic were analyzed in spring. Results show that the consistent degree of arid change is low in China, and the regional different of arid evolution was obvious, it was divided into following twelve add characteristic regions： the inner Mongolian plateau area, the Nanling mountain areas, the north of north China and Changhaishan mountain area, the Yangtze river area, the loess plateau area, the Yellow river and Huaihe area, the north of Tianshan area, the plain of northeast China area, the corridor of Hexi area, the Yunnan-Guizhou plateau area, the basin of Tarim area and Qinghai-Tibet plateau area. It is found that the spring drought index takes on descendant trend in the inner Mongolian plateau area, the north of north China and Changbaishan mountain area, the loess plateau area, the north of Tianshan area, the plain of northeast China area and the corridor of Hexi area, but it takes on ascendant trend in the Nanling mountain areas, the Yangtze river area, the Yellow river and Huaihe area, the Yunnan-Guizhou plateau area, the basin of Tarim area and Qinghai-Tibet plateau area. It is proved that the drought index exists 5 -8 a period in the most areas, it exists 12 -13 a and 15 - 16 a period in some areas, it also exists 20 a period in specific area. The regional different of add characteristic in China was obvious.