Abstract: This paper documents the effects of development in Kenya and its subsequent influence on surface temperatures. The assumption is that deforestation leads to a decrease in evapotranspiration, and causes an observed temperature increase. The study was realised in the Mau Forest of Central Kenya, where extensive deforestation over the past 20 years has caused changes in climate and hydrology. The analyses are based on processing of Landsat satellite images. Field observations during the ‘dry’ rainy season in October 2008, and testimonies of local people and scientists, confirm the decline of precipitation, low water level in lakes and discharge of rivers.