@article{FrimpongMolkenthinKoranteng2022, author = {Frimpong, Bernard Fosu and Molkenthin, Frank and Koranteng, Addo}, title = {Analysis of temperature variability utilising Mann-Kendall and Sen's slope estimator tests in the Accra and Kumasi metropolises in Ghana}, doi = {10.1186/s40068-022-00269-1}, year = {2022}, abstract = {Temperature variability may have direct and indirect impacts on the environments of the Accra and Kumasi Metropolises in Ghana. This study analysed temperature and trends in temperature in both cities using in-situ measurements from one meteorological station in both cities from 1986 to 2015. The temperature indices were computed using the RClimdex package from the Expert Team on Climate Change Detection Monitoring Indices (ETCCDMI). The temperature time series was pre-whitened before the Mann-Kendall trend and Sen's slope estimator analysis were applied. Initial analysis revealed minimal variation in temperature in both cities. The results from the analysed temperature indices revealed an increase in warm days and a general rise in the minimum temperature compared to maximum temperatures. Mann Kendall and Sen's slope revealed significant trends in the annual and seasonal (dry and wet seasons) in minimum temperature in both cities. These might lead to an increased rate of heat-stressed diseases and an overall rise in urban warming in both cities. The analysis of temperature, indices and trends provided comprehensive insights into the temperature of Accra and Kumasi. The results highlight the essence of evaluating temperature indices and trends in light of Climate Change concerns. It is recommended that urban green and blue spaces should be incorporated into land use plans as these policy directions can aid regulate the temperature in both cities.}, subject = {Temperature variability; Mann-Kendall test; Sen's slope estimator; Accra; Kumasi; Temperaturvarabilit{\"a}t; Sen-Slope Sch{\"a}tzer; Accra; Kumasi; Temperatur; Schwankung}, language = {en} } @phdthesis{Frimpong2022, author = {Frimpong, Bernard Fosu}, title = {Analysis of the relationship between spatial urban expansion and temperature utilising remote sensing and GIS techniques in the Accra and Kumasi Metropolises in Ghana}, doi = {10.26127/BTUOpen-6073}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-60730}, school = {BTU Cottbus - Senftenberg}, year = {2022}, abstract = {Accra and Kumasi are the two major cities in Ghana. Spatial urban expansion has been experienced in transforming different non-urban Land Use Land Cover (LULC) types into urban/built-up areas with a potential direct relationship to temperature rise in the cities. Thus, this dissertation aims to establish the relationship between urban spatial expansion and temperature in Accra and Kumasi metropolis. Multi-source datasets such as remote sensing images, different GIS vector layers, reference maps and historical temperature datasets were used for this retrospective study. This research was grouped under three components: environmental science, environmental technology, as well as environmental management and planning. From the environmental science component, LULC maps were produced for different years to assess the trend of temporal change in the various LULC classes in the two metropolises. Remote sensing indices and land surface temperature were retrieved from the remote sensing images to determine their correlations. Temperature time series was analysed by calculating temperature indices and determining temporal trends to reveal changes in air temperature to detect urban warming and its impacts. From the environmental technology, the novel random forest algorithm was utilised to classify the satellite images of both cities since previous works have utilised other traditional classifiers. The satellite imageries were used for point-based estimation of temperature to determine Urban Heat Islands (UHIs) hotspots. For environmental management and planning, spatial urban expansion techniques were utilised to ascertain trends in urban/built-up areas, especially in both cities' sub-metropolitan zones. For prescient purposes, future LULC modelling was implemented to provide insights into the proportions of the various LULC changes in 2025. The analysis identified two salient findings: increased urban/built-up areas at the expense of agricultural and forestlands throughout the study period and the positive correlation between spatial urban expansion and temperature. This indicated warming up of urban temperature in both cities. The major findings in this dissertation provided evidence of how integrated datasets and research techniques can be utilised for LULC changes to determine the relationship between spatial urban expansion and temperature at local scales. Institutions such as metropolitan assemblies and policymakers may adopt the concepts demonstrated in this work to rapidly assess urban environments and investigate the relationship between spatial urban expansion and temperature.}, subject = {Spatial urban expansion; Temperature; Land Use Land Cover; Remote sensing; GIS; Urbane Expansion; Temperatur; Landnutzung; Landbedeckung; Fernerkundung; Ghana; Landnutzung; Großstadt; Temperatur; Fernerkundung; Geoinformationssystem}, language = {en} }