Remote sensing lake level fluctuations in response to a changing climate

摘要

Lakes and reservoirs have long been regarded as a solution to the water problems of semi-arid regions, as well as a mitigation measure against the impacts of climate change and climate variability. However, the ability of these lakes to mitigate the impacts of climate change itself has largely been untested. In this study, we tested the utility of remote sensing in monitoring fluctuations in Lake Mutirikwi's surface area. Furthermore, we determined the nature and strength of the relationship between Lake Mutirikwi's surface area and annual rainfall total with a view to understanding the sensitivity of the lake volume to the main input of water in the lake - precipitation. Results of the study show that the volume of the lake fluctuated by between 1% and as much as 90% of the lake's capacity. We also found a significant relationship (r = 0.84, p = 0.002) between the surface area of the lake and the amount of rainfall received in the second half of the rainfall season. We conclude that Lake Mutirikwi is so sensitive to fluctuations in rainfall amounts that it does not offer much mitigation cover in the face of a changing and highly variable climate.