Paper Info
Title
Evapotranspiration Variability and Its Association with Vegetation Dynamics in the Nile Basin, 2002-2011.
Abstract
Evapotranspiration (ET) is a vital component in land-atmosphere interactions. In drylands, over 90% of annual rainfall evaporates. The Nile Basin in Africa is about 42% dryland in a region experiencing rapid population growth and development. The relationship of ET with climate, vegetation and land cover in the basin during 2002-2011 is analyzed using thermal-based Simplified Surface Energy Balance Operational (SSEBop) ET, Normalized Difference Vegetation Index (NDVI)-based MODIS Terrestrial (MOD16) ET, MODIS-derived NDVI as a proxy for vegetation productivity and rainfall from Tropical Rainfall Measuring Mission (TRMM). Interannual variability and trends are analyzed using established statistical methods. Analysis based on thermal-based ET revealed that >50% of the study area exhibited negative ET anomalies for 7 years (2009, driest), while >60% exhibited positive ET anomalies for 3 years (2007, wettest). NDVI-based monthly ET correlated strongly (r > 0.77) with vegetation than thermal-based ET (0.52 < r < 0.73) at p < 0.001. Climate-zone averaged thermal-based ET anomalies positively correlated (r = 0.6, p < 0.05) with rainfall in 4 of the 9 investigated climate zones. Thermal-based and NDVI-based ET estimates revealed minor discrepancies over rainfed croplands (60 mm/yr higher for thermal-based ET), but a significant divergence over wetlands (440 mm/yr higher for thermal-based ET). Only 5% of the study area exhibited statistically significant trends in ET.
Year
DOI
Venue
2014
10.3390/rs6075885
REMOTE SENSING
Keywords
Field
DocType
evapotranspiration,vegetation productivity,NDVI,land cover,climate,rainfall,trend analysis,Nile Basin
Vegetation,Normalized Difference Vegetation Index,Vegetation dynamics,Geology,Climatology,Evapotranspiration,Land cover,Surface energy balance,Structural basin,Precipitation
Journal
Volume
Issue
Citations 
6
7
3
PageRank 
References 
Authors
0.88
2
4
Name
Order
Citations
PageRank
Henok Alemu130.88
Gabriel B. Senay2279.85
Armel T. Kaptué330.88
valeriy kovalskyy4152.77