对印度-恒河流域地表变量季节性趋势及其驱动因素的多方面分析。

Multi-faceted analyses of seasonal trends and drivers of land surface variables in Indo-Gangetic river basins.

机构信息

German Remote Sensing Data Center (DFD), German Aerospace Center (DLR), Muenchener Strasse 20, 82234 Wessling, Germany.

German Remote Sensing Data Center (DFD), German Aerospace Center (DLR), Muenchener Strasse 20, 82234 Wessling, Germany.

出版信息

Sci Total Environ. 2022 Nov 15;847:157515. doi: 10.1016/j.scitotenv.2022.157515. Epub 2022 Jul 22.

Abstract

The Indo-Gangetic river basins feature a wide range of climatic, topographic, and land cover characteristics providing a suitable setting for the exploration of multivariate time series. Here, we collocated a comprehensive feature space for these river basins including Earth observation time series on the normalized difference vegetation index (NDVI), surface water area (SWA), and snow cover area (SCA) in combination with driving variables between December 2002 and November 2020. First, we evaluated changes using multi-faceted trend analyses. Second, we employed the causal discovery algorithm Peter and Clark Momentary Conditional Independence (PCMCI) to disentangle interactions within the feature space. PCMCI quantifies direct and indirect relationships between variables and has been rarely applied to remote sensing applications. The results showed that vegetation greening continues significantly. Irrigated croplands in the Indus basin indicated the highest trend magnitude (0.042 NDVI/decade). At annual and basin scale, positive trends were also identified for SWA in the Indus (837 km/decade) and Ganges basin (677 km/decade). Annual trends in SCA were insignificant at basin scale. Considering elevation zones, negative SCA trends were found in high altitudes of the Ganges and Brahmaputra river basins. Similarly, NDVI and SWA showed positive trends in high elevations. Furthermore, the causal analysis revealed that NDVI was controlled by water availability. SWA was directly influenced by river discharge and indirectly by precipitation. In high altitudes, SWA was controlled by SCA and temperature. Precipitation and temperature were identified as important drivers of SCA with spatio-temporal variations. With amplified climate change, the joint exploitation of time series will be of increasing importance to further enhance the understanding of land surface change and complex interplays across the spheres of the Earth system. The insights of this study and used methods could greatly support the development of climate change adaptation strategies for the investigated region.

摘要

印度-恒河流域具有广泛的气候、地形和土地覆盖特征,为探索多元时间序列提供了适宜的环境。在这里,我们为这些流域配置了一个综合的特征空间,包括地球观测时间序列的归一化差异植被指数(NDVI)、地表水面积(SWA)和雪盖面积(SCA),以及 2002 年 12 月至 2020 年 11 月期间的驱动变量。首先,我们使用多方面的趋势分析来评估变化。其次,我们采用因果发现算法 Peter 和 Clark 瞬时条件独立性(PCMCI)来分解特征空间内的相互作用。PCMCI 量化了变量之间的直接和间接关系,并且很少应用于遥感应用。结果表明,植被持续明显变绿。印度河流域的灌溉耕地表现出最大的趋势幅度(0.042 NDVI/decade)。在年际和流域尺度上,印度河(837 km/decade)和恒河(677 km/decade)流域的 SWA 也呈现出正趋势。在流域尺度上,SCA 的年际趋势不显著。考虑海拔区域,恒河和雅鲁藏布江流域的高海拔地区出现了负 SCA 趋势。同样,NDVI 和 SWA 在高海拔地区呈现出正趋势。此外,因果分析表明,NDVI 受水可用性控制。SWA 直接受河川径流量影响,间接受降水影响。在高海拔地区,SWA 受 SCA 和温度控制。降水和温度是 SCA 的重要驱动因素,具有时空变化。随着气候变化的加剧,对时间序列的联合开发将变得越来越重要,以进一步增强对陆地表面变化和地球系统各领域复杂相互作用的理解。本研究的见解和所使用的方法将极大地支持为研究区域制定气候变化适应战略。

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索