| 摘要: |
| 本文基于长时间中国雪深长时间序列数据集（1979-2021）以及中国区域地面气象要素驱动数据集（1979-2018）分析了青藏高原地区近40年雪深的时空变化特征以及其与近地面气温、降水的偏相关性。时空变化分析结果显示，青藏高原地区雪深在年尺度上呈现出以高原内部及南部边缘区域的雪深减少为主的变化趋势，而这种趋势在月尺度以及秋冬两季更为显著；受东亚季风影响的高原东部是雪深显著增加的主要区域。偏相关分析发现，雪深在月、季和年尺度上均与气温有着较大的负相关性，最大负偏相关系数均在-0.8上下；而雪深与降水在年、月尺度上以正相关为主且有着相似的空间分布，二者的相关性在春、夏两季共同呈现出“东正西负”的分布格局，而大范围的正相关性（偏相关系数在0.4以上）集中在秋季。雪深与降水间的偏相关性在季节上的显著差异主要体现在受印度季风以及西风影响的高原西北部。在日尺度上，气温与延迟10天后的雪深呈现出最大负相关性（相关系数为-0.733）；而降水则与延迟3天后的雪深呈现出最高的正相关性（相关系数为0.064）。青藏高原雪深与气象要素的相关性表现出明显的时空异质性，地形、融积时间乃至高原周围的季风与西风都可能是导致这种时空差异性的原因。 |
| 关键词: 积雪深度 青藏高原 时空变化 偏相关分析 |
| DOI： |
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| 基金项目:国家重点研发计划项目 |
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| Temporal and spatial variation of snow depth and its partial correlation with meteorological factors on the Qinghai-Tibet Plateau during the recent 40 years |
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She Wangkang1, Yang Qinli1, Wang Guoqing2, Jin Shuangyan3
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1.School of Resources and Environment,University of Electronic Science and Technology of China;2.State Key Laboratory of Hydraulic-Water Resources and Hydraulic Engineering,Nanjing Hydraulic Research Institute;3.Bureau of Hydrology,Yellow River Conservancy Commission
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| Abstract: |
| Based on long-term series of daily snow depth dataset in China (1979-2021) and China meteorological forcing dataset (1979-2018), this study presents the temporal and spatial variation characteristics of snow depth on the Qinghai-Tibet Plateau in the past 40 years and further analyzes its partial correlation with near-surface temperature and average precipitation. The results of spatiotemporal variation analysis show that the snow depth on the Qinghai-Tibet Plateau exhibits a decreasing trend mainly in the interior and southern edge areas of the plateau, and this trend is more significant on monthly scale and in autumn and winter. The eastern part of the plateau, affected by the East Asian monsoon, is the main area for the significant increase in snow depth. Partial correlation analysis shows that snow depth has a large negative correlation with temperature on all scales, and the maximum negative partial correlation coefficient is around -0.8, while snow depth and precipitation have similar spatial distribution and different correlation ranges on annual and monthly scales. As a whole, the correlation between snow depth and precipitation shows a distribution pattern of "positive in east and negative in west" in spring and summer, and the more common positive correlation is concentrated in autumn, during which most areas have a positive correlation of above 0.4. The significant seasonal differences between the two are reflected in the northwestern plateau affected by the Indian monsoon and westerlies. On the diurnal scale, temperature has the largest negative partial correlation (-0.733) with snow depth after a delay of 10 days, while precipitation has the highest positive correlation (0.064) with snow depth after a delay of 3 days. The variation characteristics of snow depth and meteorological correlation on the Qinghai-Tibet Plateau show obvious spatiotemporal heterogeneity. Topography, ablation and accumulation time, and monsoons and westerlies around the plateau may be the reasons for this spatiotemporal difference. |
| Key words: snow depth Qinghai-Tibet Plateau spatiotemporal variation partial correlation analysis |
