柴达木盆地气候变化的区域显著性及其成因研究

Regional Differences of Climate Change in Qaidam Basin and Its Contributing Factors

利用1961—2013年柴达木盆地气温、降水等气象资料和高原季风、西风环流等相关大气环流及植被覆盖数据分析了柴达木盆地气候变化时空规律,揭示了其区域气候变化显著性的成因。研究表明:近53 a来柴达木盆地气候变化呈显著增暖趋势,年平均气温气候倾向率达0.48℃/10 a,增幅明显高于整个青藏高原乃至全国和全球平均水平;滞后于变暖,柴达木盆地气候趋于明显变湿,其降水量和降水日数均呈增多趋势,达到95%以上信度的显著性水平;气候暖湿化具有明显的经向地带性分布规律,气候变暖显著的区域气候变湿相对不甚明显,反之亦然;在全球变化背景下,太阳辐射减小、高原季风趋于强劲、西风环流略弱和盆地植被覆盖恢复并具有明显的经向地带性变化特征,是造成柴达木盆地气候变化具有上述区域特征的气候成因。

By analyzing the spatial and temporal characteristics of the meteorological data such as temperature and precipitation, and the information of plateau monsoon, atmospheric circulation, and vegetation cover from 1961 to 2013, the climate contributing factors of regional differences are revealed. It is found that the climate change showed a significant warming trend in recent 53 years in Qaidam Basin. The climate trend rate of annual mean temperature attained0.48 ℃/10 a, that the amplitude is higher than that of the whole Qinghai-Tibet Plateau obviously, even that of the national and global levels. Lagging behind the warming, it is apparently becoming wetter in Qaidam Basin. The precipitation and the rainfall days showed a tendency of increase at more than 95% confidence level. The distribution of warm and humid change showed distinct longitudinal zonality. The regions getting warmer significantly usually did not turn wetter obviously, and vice versa. In the global warming situation, solar radiation reduction,the tendency of the plateau monsoon being stronger, the weaker westerly circulation, and the recovery of the vegetation, which all have the distinct characteristics of longitudinal zonality, are the contributing factors to the regional differentiation of the climate change in Qaidam Basin.