Abstract:
Urban Heat Island (UHI) is a phenomenon characterized by higher surface
and atmospheric temperatures in urbanized areas as compared to the surrounding
rural areas. This phenomenon is a consequence of increase in Land
Surface Temperatures (LST) as a result of trapped heat energy on the surface.
The objective of this study is establishing the trends in and relationship between
LST and land use/land cover in Nakuru County as it seeks to achieve
the ultimate goal to contain the UHI effect. Urban heat island inference was
based on the generation of a time series set of Landsat imagery, with particular
emphasis on the thermal band. Land use/land cover mapping was conducted
using maximum likelihood classification techniques, and this, like the
LST, is generated in a time series fashion from 1989 to 2015. Accuracy assessment
was conducted in order to give confidence in the classification results.
The accuracy of the development was assessed using observed temperature
data as recorded by the ground stations at the Kenya Meteorological Department.
This study employed Normalized NDVI and NDBI to investigate
the variation land use/land cover. Results revealed that over the years, settlement
has been on an upward trend in terms of area whereas forests have been
decreasing due to deforestation. Also, the land surface temperatures have been
increasing over the years. In order to qualify this, the correlation between LST
and Land Use change was conducted and it indicated that changes to settlement/urban
increased proportionately with Land Surface Temperature.
