全球气候变化将对农田、林地、草原等生态系统产生不同程度的影响，而制定科学合理的气候变化应对策略，需要准确把握区域气候变化的时空特征与规律。为了全面了解西藏地区温度和降水指标的时空格局，深入分析了1971—2010年间的年平均温度和降水量年值及季节值的变化趋势和时空格局。结果表明，（1）年平均温度普遍升高，有39.72%的地区累计升高1.6~2.4℃，10.72%的地区累计升高2.4~3.2℃，局部地区累计升高4℃以上，在空间分布上，仅错那县、墨脱县和察隅县三县的南部地区年平均温度下降，其余地区年平均温度升高。从降水量变化来看，有42.09%的区域变化在±1 mm∙a-1之间，与40年前相比，有12.41%的地区年降水减少40 mm以上，45.49%的地区呈增加趋势。从空间分布来看，降水量减少区域主要分布在阿里东北到那曲西北一带、日喀则西部到阿里狮泉河一带、日喀则南部以及林芝东南部。（2）从季节平均温度、降水量的变化来看，4个季节温度均以升高为主，增幅高低顺序为秋季>春季>冬季>夏季；四季降水量差异较大，春季和夏季以增多为主，秋季和冬季以减少为主，其中，冬季减少最多，面积占比达96.78%。（3）近40年来，温度变化存在显著的突变点，突变时间存在空间分异性。（4）温度的明显升高和降水量的时空差异将导致局部地区气候干湿变化。藏西地区易发生全年干旱，藏南和藏东南地区易发生季节干旱，这将给农业生产、天然草地牧草生长和草原畜牧业带来不利影响。研究认为相关部门和农牧民都应该重视并尽快制定科学合理的应对策略和方案，以应对不确定性的气候变化。%In the context of global climate change, climate change will affect the ecological environment of agriculture, forestry and grassland to varying degrees. To formulate a scientific and reasonable climate change response strategy, we need to accurately grasp the temporal and spatial characteristics and laws of regional climate change. In order to comprehensively analyze and understand the spatial and temporal pattern of temperature and precipitation in Tibet, the annual mean temperature and annual precipitation value and the seasonal variation trend and spatial-temporal pattern of 1971—2010 were analyzed. The results show that: (1) The annual average temperature increased in general, 39.72% of the total area increased 1.6~2.4℃, 10.72% of the total area increased 2.4~3.2℃, some areas increased by 4℃ above.The spatial distribution:only the average annual temperature in the southern region of the three counties (Cuona, Medog and Zayu counties) decreased, while the average temperature in other areas increased. Precipitation change: 42.09% of the area changes in ±1 mm∙a-1, 12.41% of the area (compared with 40 years ago), the annual precipitation decreased by 40mm above, 45.49% area shows an increasing trend. The spatial distribution of precipitation: precipitation reduction area is mainly distributed in the northeast of Ali to the northwest of Naqu, Shigatse west to Ali Shiquanhe area, south of Shigatse and southeast of Nyingchi. (2) The seasonal mean temperature and precipitation of the four seasons showed that the temperature increased in all four seasons, the order of increase was autumn>spring>winter>summer; The precipitation in the four seasons is greatly different, and the increase is mainly in the spring and summer, and the decrease is mainly in the autumn and winter, among the four seasons the precipitation of winter decreased the most reached an area of 96.78%. (3) During the recent 40 years, the temperature change has obvious mutation point, and the mutation time has spatial differentiation. (4) Due to the obvious increase of temperature and the difference of precipitation, it will lead to the change of dry and wet climate in some areas. The drought in the western part of Tibet is easy to occur throughout the year. Seasonal drought is easy to occur in southern Tibet and southeastern Tibet, which will adversely affect agricultural production, natural grassland forage growth and grassland animal husbandry. The study suggests that the relevant departments and farmers and herdsmen should pay attention to and formulate scientific and reasonable response strategies and programs as soon as possible to deal with the uncertainty of climate change.
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