An Analysis On The Regionality And Causes Of Climatic Environmental Records Of The Little Ice Age In China

The research on global climate change has already become one of the mostimportant research focuses in areas like politics, economy and science. In the last twodecades of20thcentury, its regional research has acquired extensive and profoundachievements, combining the global and regional problems more explicitly andreaching a common ground that the research of global problems should beaccomplished by the research of regional problems which should represent the globalone. In addition, integration research is a significant means to turn the achievementsof the regional research into global one.The Little Ice Age, roughly consisted of three cool fluctuations, is the latestglobal cold climate event. This paper, by using integration research, analyzes globalindex records which have clear orientation, higher time resolution and thecharacteristics of climate. And it, by using Mapinfo, also traces, describes andcompares the characteristics of environmental evolution of the Little Ice Age withinthe country. It also investigates the starting and ending time and climaticcharacteristics of the cooling fluctuations within the Little Ice Age in China. Throughcombing the atmospheric circulation pattern influencing our country, such as El Nino,La Nina and Pacific Decadal Oscillation, explores weather pattern of our countrytentatively. At the same time, it compares the climatic evolution information of crucialcircumjacent areas like North/South Atlantic Oceans, Pacific Ocean and North/SouthAmericas; systematically elaborates phenomena of climate events in the Little Ice Ageand the mechanism of their possible reasons and social influence. The researchsuggests that:(1) The general trend of changes in warm and cold periods, usually three coldperiods and two warm ones, is consistent. But there are differences in the starting andending time of cool fluctuations during the Little Ice Age. Three cold periods duringthe Little Ice Age in China:1440AD±20~1520AD±20.1610AD±10~1720AD±10and1790AD （1820±10）~1890AD. They correspond to Sprer Minimum, MaunderMinimum and Dalton Minimum of solar radiation respectively;(2) Collects the starting and ending times of different cool fluctuations during theLittle Ice Age in Qinghai Area, the transitional Middle Area and Eastern Arearespectively. Among them, Qinghai Area enters the cold period first and the easternarea last. And their starting and ending times put off20~50a successively, which the Qinghai-Tibet Plateau is the launch area of the weather in our country. And in variousareas, the sub-cold periods during the Little Ice Age are different in strength. Tracingthe records of climate reconstructions shows that the second cold period is thestrongest in most areas, while the third cold period is the strongest in southwest andsouthern China;(3) During the Little Ice Age, the vibration of the precipitation range is frequent,and the distribution of the dry and wet space is various. It analyzes the climate indexrecords of high resolution synthetically, and draws the distribution of dry and wetcondition of our country, which shows that the area of cold and wet type is more thanthat of cold and dry. The regions of cold and wet are the West-North district(including Xinjing province and the west Kunlun Mountains), the Qinghai-TibetPlateau, Northeast China Region, the Yellow River Basin, the middle and lowerreaches of Changjiang River and the south China Region, especially the North-Westdistrict, the Qinghai-Tibet Plateau and the Yangtze-Huaihe river basin. Regions likethe South-West region, the areas of farming and pasturing (Inner Mongolia, the regionof Shaan-Gan-Ning and Qilian Mountain) and the Haihe River basin are lessinfluenced by Indian monsoon and Eastern Asian monsoon, with less precipitation andcolder and drier. This pattern accords with the weather in our country when NorthAtlantic Oscillation increases, the La Nina in the Middle East and the Pacificdominates and the decadal oscillation index in the Pacific is in the positive phase;(4) Studies the data of solar radiation and volcanic aerosol between1100AD to1950AD. In the meantime, it also analyzes the law of the changes of dynasties. Itsuggests that the climatic abnormality under the influence of solar activity and thevesuvian eruption is one of the main causes that changed the dynasties in our history.