Influence of global climate on freshwater changes in Africa's largest endorheic basin using multi-scaled indicators

被引：16

作者：

Ndehedehe, Christopher E. ^{[1
,2
]}

Ferreira, Vagner G. ^{[3
]}

Onojeghuo, Alex O. ^{[4
]}

Agutu, Nathan O. ^{[5
]}

Emengini, Ebele ^{[6
]}

Getirana, Augusto ^{[7
,8
]}

机构：

[1] Griffith Univ, Australian Rivers Inst, Nathan, Qld 4111, Australia

[2] Griffith Univ, Griffith Sch Environm & Sci, Nathan, Qld 4111, Australia

[3] Hohai Univ, Sch Earth Sci & Engn, Nanjing, Peoples R China

[4] JOLEXY Envirom Serv Ltd, Edmonton, AB, Canada

[5] JKUAT, Dept Geomat Engn & Geospatial Informat Syst, Nairobi, Kenya

[6] Nnamdi Azikiwe Univ, Dept Surveying & Geoinformat, Awka, Anambra State, Nigeria

[7] NASA, Goddard Space Flight Ctr, Hydrol Sci Lab, Greenbelt, MD USA

[8] Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA

来源：

SCIENCE OF THE TOTAL ENVIRONMENT | 2020年 / 737卷

基金：

美国国家航空航天局; 美国海洋和大气管理局;

关键词：

Sentinel-2; Remote sensing; Drought; Surface water; AMO; Climate variability; LAKE CHAD; WEST-AFRICA; VEGETATION DYNAMICS; LOGONE CATCHMENT; GREATER HORN; DROUGHT; VARIABILITY; IMPACT; PRECIPITATION; PATTERNS;

D O I：

10.1016/j.scitotenv.2020.139643

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

The poor investments in gauge measurements for hydro-climatic research in Africa has necessitated the need to investigate how decision makers can leverage on sophisticated space-borne measurements to improve knowledge on surface water hydrology that can feed directly into water accounting processes, and risk assessment from extreme droughts and its impacts. To demonstrate such potential, a suite of satellite earth observations (Sentinel-2, altimetry, Landsat, GRACE, and TRMM) and model data are combined with the standardized precipitation evapotranspiration index to assess the impacts of global climate on freshwater dynamics over the LCD (Lake Chad basin), Africa's largest endorheic basin. As shown in the results of this study, the significant relationship of climate modes (AMO; r=0.68 and 059; and AMM; r=0.42 and 0.47) with drought patterns in the LCB highlights the evidence of global climate influence in the region. The significant declines in drought extents and their intensities (2004 - 2015) over LCB coincide with the rise in surface water extent of the Lake Chad during the same period. Change detection analysis of open water features in the southern pool of Lake Chad during the 2015 - 2019 period shows that on the average, only 28.4% of inundated areas within the vicinity of the Lake persisted during the period. While the association of terrestrial water storage (TWS) with model-derived surface water storage (SWS) is strongest (r=0.89) in the catchments that provide the most nourishment to the Lake Chad, the relationship of rainfall (2002 - 2017) with TWS (r=0.85), model TWS (r=0.87) and SWS (r=0.88) confirm that the LCB's hydrology is predominantly climate-driven. This notion is further reinforced as the predicted SWS over the LCB using a support vector machine regression scheme was found to be strongly correlated (r=0.95 at alpha=0.05) with observed SWS. (C) 2020 Published by Elsevier B.V.

引用

页数：19