杜佳玉,陶丽. 2022. 中国降水的年代际变化及全球变暖、IPO、AMO对其的相对贡献[J]. 气象学报, (0):-, doi:[doi]
中国降水的年代际变化及全球变暖、IPO、AMO对其的相对贡献
Interdecadal Variation of Land Precipitation in China and the Relative Contribution of Global Warming, IPO and AMO to It
投稿时间:2021-10-24  修订日期:2022-02-19
DOI:
中文关键词:  全球变暖,IPO,AMO,相对贡献,华北降水机制
英文关键词:GW, IPO, AMO, Relative contribution, Precipitation mechanism in North China
基金项目:国家重点研发计划
作者单位邮编
杜佳玉 南京信息工程大学 210044
陶丽 南京信息工程大学 210044
摘要点击次数: 21
全文下载次数: 19
中文摘要:
      虽然我国降水以年际变化为主,但可利用奇异谱分析(SSA,Singular Spectrum Analysis)辨析出10-20年、20-50年年代际变化的显著性区域以及>50年的长期趋势的显著性区域。并通过奇异值分解(SVD,Singular Value Decomposition)、多元线性回归等多种方法,探究了1934-2018年期间不同海洋模态对6-8月和12-2月我国陆地降水的趋势以及年代际振荡的相对贡献。通过对中国降水及中低纬地区海温(SST,Sea Surface Temperature)进行SVD分析发现,不论冬夏影响中国降水的主要模态是全球变暖(GW, Global Warming),其次是太平洋年代际振荡(IPO,Interdecadal Pacific Oscillation)。利用多元线性回归模型定量评估GW、IPO、大西洋多年代际振荡(AMO,Atlantic Multidecadal Oscillation)对中国不同区域降水的方差贡献及各因子的相对贡献,结果表明:夏季, 三者可以解释西北和华北大约30%的年代际降水,其中GW的相对贡献最大、IPO次之;冬季,三者可以解释东北42%、西北和华北30%左右的年代际降水,东北和西北以GW的相对贡献为主、AMO为辅,华北仍以GW影响为主、IPO为辅。鉴于华北不论冬夏均以GW趋势为主、IPO影响次之,聚焦华北,探究其夏季降水减少机制,GW会导致环贝加尔湖地区气温异常增暖,相应低层有反气旋性环流,华北地区有异常偏北风和下沉气流,从而华北降水减少,这与前人研究一致。
英文摘要:
      Although the interannual variability of land precipitation across China are more important, we use singular spectrum analysis (SSA) to obtain the areas of significant variability of decadal (10–20 a), multidecadal (20–50 a) and secular trends (>50 a). In addition, the relative contribution of different SST modes to the trend and decadal variability of precipitation over China during JJA/DJF of 1934-2018 was investigated by singular value decomposition (SVD) and multiple linear regression methods. Based on SVD analysis of precipitation in China and SST in middle and low latitudes, it is found that global warming (GW) is the primary SST mode affecting precipitation of China whether in winter or summer. Pacific Interdecadal Oscillation (IPO) play a second role. Then multivariate linear regression model is applied to quantitatively evaluate the variance contribution and relative contribution of GW, IPO and AMO to precipitation in different regions of China. The results show that GW, IPO and AMO can explain about 30% of the interdecadal precipitation in Northwest China and North China in summer, and the relative contribution of GW is the largest, followed by IPO. In winter, the three factors can explain 42% of that in Northeast China and about 30% in Northwest China and North China. In Northeast China and Northwest China, the relative contribution of GW is dominant, second to it is AMO. While in North China, GW is still dominant, second to it is IPO. Considering that GW is the dominant contributor over North China both in winter and summer, we further explore the mechanism of the downward trend of summer precipitation over North China. The results show that the increase of the air temperature cause an anomalous low-level anticyclone over the Lake Baikal region and lead to abnormal northerly wind and abnormal downward motion in North China which response to the decreased precipitation there. It is consistent with other studies.
查看全文   查看/发表评论  下载PDF阅读器
分享按钮