Spatio-temporal dynamics of water level of the African Great Lakes in the past three decades

Keywords: Remote Sensing, GIS, Satellite Radar Altimetry, Lake Water Level/Storage
Abstract Type: Paper Abstract

Abstract

The African Great Lakes are a series of lakes located in and around the East African Rift Valley. Collectively, these lakes constitute about 25% of the planet's unfrozen surface fresh water and provide drinking water for tens of millions of people in Africa. It is one of the most important regions for conservation in Africa. The water levels and storage volume of the African Great Lakes have rapidly changed over the past century. Monitoring lake water level and storage change is essential for predicting possible droughts, floods, and for assessing water resources for drinking, agriculture, aquaculture, fisheries and food security. Most lakes in this region do not have gauge stations to measure their water levels. In this research, we will utilize satellite radar altimetry to measure and analyze the lake water level/storage variability in the past three decades. Based on satellite radar altimetry observations during 1992-2022, we can decompose the temporal lake water level variations into the trend, seasonal, and noise components using the Bfast (Breaks for Additive Season and Trend) model. The long-term trends, trend breaks, and seasonal pattern of lake water level variations have been examined for 19 largest lakes in the region, and the underlying drivers for the spatio-temporal dynamics of the lake water level in East South Africa are explored.