干旱区生态环境知识资源中心(Arid): 中国西北气候由暖干向暖湿转型的特征和趋势探讨

Arid

	中国西北气候由暖干向暖湿转型的特征和趋势探讨
其他题名	Discussion on the present climate change from warm-dry to warm-wet in northwest china
	施雅风 1; 沈永平 1; 李栋梁 1; 张国威 2; 丁永建 1; 胡汝骥 3; 康尔泗 1
来源期刊	第四纪研究
ISSN	1001-7410
出版年	2003
卷号	23 期号:2 页码:152-164
中文摘要	由于全球显著变暖和水循环加快，使得中国西北主要是新疆地区于1987年气候发生突然变化，随着温度上升，降水量、冰川消融量和径流量连续多年增加，内陆湖泊水位显著上升，洪水灾害也迅猛增加，同时，植被有所改善，沙尘暴日数锐减，从而改变了19世纪末期至20世纪70年代的变暖变干趋势。以降水量增加超过蒸发量增加所导致的径流量增长及湖泊水位上升作为气候向暖湿转型的主要标准，西北地区目前的气候变化可分为3个区域，即1）显著转型区；2）轻度转型区；3）未转型区。作者初步认为，西北气候向暖湿转型可能是世纪性的，预期西北东部在21世纪上半期也会向暖湿转变，但预测有较大的不确定性。
英文摘要	Under the global warming, mainly in northwest China, the climate was basically characterized by the development of warm-dry since the end of the little ice age until 1980s. A climatic mutation to warm-wet happened in 1987. Since 1980s, air temperature has been increasing more rapidly.The average annual temperature during 1987 to 2000 had risen by 0.7℃ as compared with that during 1961 to 1986. Nevertheless, with the rising of temperature, precipitation and glacial melt water increase rapidly widespread. As compared with the period from 1961 to 1986, the average precipitation during 1987 to 2000 increased by 22% in the north Xinjiang, 33% in the south Xinjiang, and 10% to 20% , the middle and west Hexi Corridor area and some areas in the Qinghai-Xizang Plateau, but most of the increasing precipitation failed on the Tianshan Mountains, the Qilian Mountains and other mountains with few actual records. For the increase of glacial melt water, No. One glacier at the source area of the Urumqi River which has had field measurements and monitoring for several decades is taken as an example, the average annual melt water from 1985 to 2001 increased by 84.2 % as compared with that during the years from 1958 to 1985. Whereas in the east region of northwest China, the conditions were in the opposite, it was still under the warm-dry climate, precipitation decreasesd by 5% to 15% and the draught occurred frequently during the compared periods as above mentioned.Along with the increase of precipitation, the hydrological conditions and ecological environment were also correspondently changed. Most rivers in Xinjiang, the rivers at the middle and west Qilian Mountains of Gansu Province and at the southeast Qaidam Basin of Qinghai Province had experienced the trend of annual runoff increase since 1987, and the increase range was averaged at more than 5% , and was above 20 % in most regions and the maximum increase range arrived at 40% from the years of 1956 to 1986 to the years of 1987 to 2000. The lake-levels of the most influenced inland lakes by the increase of precipitation, such as the Bosten Lake and the Ebinur Lake, had continuously and rapidly risen since 1987. The lake-level of Bosten Lake was risen with 4.5m from 1987 to 2002, exceeding the highest lake-level during 1950s. The area of wide and shallow Ebinur Lake had been enlarged from 499km~2 in 1987 to 1064km~2 in 2002, resuming the high lake-level in 1957. Along with increase of precipitation, flood disasters happened frequently. In the existing records of flood disasters, the most serious ones occurred in 1987, 1996 and 2002, and the damage of 1996 flood disaster was extremely serious in Xinjiang. However, the climate change from warm-dry to warm-wet brings much more benefits than harms. The mean annual mountain water resources of Xinjiang during the years from 1987 to 2000 was increased by 7% , about 62.1*10~8m~3/a, as compared with that during the years from 1956 to 1986. The vegetation index was obviously increased in the area of north and west Xinjiang, where precipitation increased in a larger amount. In northern part of China, especially in the Xinjiang area, the days of sand-dust storms were rapidly decreased because of the reduction of strong windy days.Above-mentioned evidences indicate that the regional climate of northwest China had showed the trend climate change from the warm-dry pattern to the warm-wet pattern. Through comprehensive evaluation and analysis of the evidences and signals, the present climate change of northwest China can be classified into three regions. The first is the notable change region of climatic pattern with marked becoming wet, mainly in the north Xinjiang, the Tianshan Mountains and their both sides, the west Tarim Basin, the down course area of the Yarkant River, west and central part of the Qilian Mountains, and the area of southwest Qaidam Basin. The west boundary of this region should go into the Central Asia countries where the range is difficult to determine because of the lack of information. The second is the slight change region of climatic pattern with some trend of becoming wet, mainly in the grand Taklimakan Desert, the desert area at the east Xinjiang, the west Gansu and inside the Qaidam Basin, where it is extremely dry and the actual evaporation is also limited, and it is estimated that the precipitation is impossible to increase largely there. The third is the unchanged region of climatic pattern with persistent drought, mainly in the east area of northwest China, and less precipitation was still in the years of 1990s.Through the analysis of the moisture transportation and atmospheric circulation, it is considered that northwest China is affected by various atmospheric circulation patterns. In the Xinjiang area, the climate is affected mostly by the westerly current coming from the Atlantic Ocean and the Arctic Ocean. However during 1980s and 1990s, the atmospheric moisture content increased obviously, caused by the rapid global warming which enhances the northwards transportation of moisture mainly from the Indian Oceans, and also partly from the westerly current.By means of modeling, statistical and period analysis, similarity and comparison analysis of paleoclimatology, a speculation is made, in despite of large uncertainties. Most probably, the time scale of present climate change from warm-dry to warm-wet in northwest China would be the centenary with the decadal fluctuation at a new warm-wet level of climatic pattern. Spatially, under the global warming, the still warm-dry climatic pattern in the east area of northwest China could be changed into the warm-wet pattern not long, and it would become wet in the whole area of northwest China to 2050.
中文关键词	中国 ; 气候变化 ; 暖干气候 ; 暖湿气候 ; 气候转型 ; 西北地区 ; 气温 ; 降水量
英文关键词	climate change warm-dry warm-wet change of climatic pattern
语种	中文
国家	中国
收录类别	CSCD
WOS类目	GEOLOGY
WOS研究方向	Geology
CSCD记录号	CSCD:1332658
来源机构	中国科学院新疆生态与地理研究所
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/203953
作者单位	1.中国科学院寒区旱区环境与工程研究所, 兰州, 甘肃 730000, 中国; 2.新疆维吾尔自治区水文水资源局, 乌鲁木齐, 新疆 830010, 中国; 3.中国科学院新疆生态与地理研究所, 乌鲁木齐, 新疆 830011, 中国
推荐引用方式 GB/T 7714	施雅风,沈永平,李栋梁,等. 中国西北气候由暖干向暖湿转型的特征和趋势探讨[J]. 中国科学院新疆生态与地理研究所,2003,23(2):152-164.
APA	施雅风.,沈永平.,李栋梁.,张国威.,丁永建.,...&康尔泗.(2003).中国西北气候由暖干向暖湿转型的特征和趋势探讨.第四纪研究,23(2),152-164.
MLA	施雅风,et al."中国西北气候由暖干向暖湿转型的特征和趋势探讨".第四纪研究 23.2(2003):152-164.