||Monitoring the Surface Temperature of Lake Victoria Using Modis Imagery
||M.W. Muhindo, A. Gidudu
||MODIS, Remote Sensing, Lake Surface Temperature, Bio-Optical Algorithms.
||The temperature cycle of Lake Victoria is not well documented as only a limited number of in-situ measurements are available. Hence they cannot account for the spatial distribution of the temperature pattern within a lake and more importantly they are not monitored regularly because of the high costs involved. Satellite technology has improved the ability to measure Lake Surface Temperature (LST) by enabling frequent coverage. The satellite-measured LST provides both the synoptic view of the lake and a high frequency of repeated views allowing the examination of basin-wide upper lake dynamics that is not possible with conventional methods. This paper demonstrates the use of MODIS Level 2 imagery of Lake Victoria to monitor LST. The MODIS data available was for the year 2009. LST was extracted from the MODIS imagery using the Long Wave algorithm developed by the National Aeronautics and Space Administration (NASA). From the results, it is evident that there was irregular variation of LST over Lake Victoria. It was characterized by high LSTs from April to May and October to November and low LST values in June to September. It was observed that these high LST coincided with the rainy season, high Inter Tropical Convergence Zone (ITCZ) and low wind speeds. Conversely, low LST coincided with the dry seasons, low ITCZ and high wind speeds. The algorithms implemented in this study are generic and ocean water based, therefore unique and site specific bio-optical algorithms or models need to be developed specifically for monitoring LST on Lake Victoria. This paper furthermore recommends the exploration of a bigger dataset to improve the understanding long term LST variations.
||The first Conference on Advances in Geomatics Research (2011)