气候变化与自然灾害

气候变化与自然灾害是当今科学研究的两大热点，两者之间在一定程度上具有相关性，但目前要确切地定量计算气候变化对自然灾害的强度和出现频率的影响还很困难。本文在分析气候变化与自然灾害关系的基础上，研究了气候变化对我国自然灾害的影响。研究结果显示：１．在千年尺度上，长江流域的大旱和气候变冷成正相关，而长江流域的大涝以及黄河流域的大旱和大涝与气候冷暖过渡期成正相关；２．在百年尽度上，近１０４２年来，共出现２８１次全国性大旱和大涝，平均每百年出现２７次，在地域分布上以南涝北旱为主；３．就百年至千年尺度的气候变化对自然灾害的影响而言，气候冷冷组合期（１３０１～１９００）易发生全国性大涝，而冷暖组合期（９５０～１３００年，１９０１～１９９１年）易发生全国性大旱。总的来说，冷冷组合期的大旱大涝发生频率明显大于暖期，但不同地区有差异；４．在其它影响方面，台风、地震与海啸灾害在冷暖组合期（２０世纪）均有比冷冷组合期（１４和１９世纪）多的趋势。因此，气候变暖将使防灾任务更加艰巨。

CLIMATE CHANGE AND NATURAL DISASTER

Climate change and natural disaster are two fundamental aspects concerned by international scientific circles.General speaking,there exists relationship between climate change and natural disaster in certain extend.However,at present,people do not exactly know in quantity how climate change would inluenec natural disaster in terms of strungth and occurring rfequency. In this paper,the relationship between climate change and natural disaster,as well as impacts of climate change on China has been studied,the priliminary results show as follows: 1 On time scale of thousand years,there exist positive relationships between severe drought years in the Yangtze River and climate tending towards cold, and between severe flood in the yagntze River and drought and flood in the Yellow River and cold/warm climate transitive period; 2 On time scale of hundred years,during past 1042 years there totally occurred 281 times country wide severe droughts and follds with rfequency of 27 times every hundred years,which were mainly characterized by drought in the North and flood in the South; 3 Impacts of climate change on natural disaster combining hundred and thousand years time scale,it seems that country wide floods occurred more often in the period of cold warm combination,and on the whole, frequency of country wide droughts and follds occurred in the period of cold cold climate combination were much hingher than that occurred in the period of cole warm combination,but the response of the regions to climate change are quite different; 4 As for the impacts of chimate change on other matural disasters,it seems that typhoon landed on China in the period of cold warm climate combination(20th century) were more than that occured in the period of cold cold climate combination,and earthquake and tsunami occurred in the period of cold warm climate combination(20th century)were more than that occurred in the period of cold cold climate combination(from 14th to 19th century).It reminds us to draw attention on prevention of natural disasters during the period of climate warming.