Investigation of Potential Prevailing Wind Impact on Land Surface Temperature at Gas Flaring Sites in the Niger Delta, Nigeria.

Authors : Barnabas MORAKINYO, Samantha LAVENDER, Vıctor ABBOTT

Pages : 179-190

Doi:10.30897/ijegeo.968687

View : 14 | Download : 8

Publication Date : 2022-03-06

Article Type : Research Paper

Abstract :This research examines the effects of South prevailing wind on Land Surface Temperature insert ignore into journalissuearticles values(LST); retrieved from Earth Observation insert ignore into journalissuearticles values(EO); Satellites at 11 gas flaring sites in Rivers State, Niger Delta region, Nigeria. 7 Landsat 5 Thematic Mapper insert ignore into journalissuearticles values(TM); and 18 Landsat 7 Enhanced Thematic Mapper Plus insert ignore into journalissuearticles values(ETM+); from 17/01/1986 to 08/03/2013 with < 5 % cloud contamination were considered. All sites are located within a single Landsat scene insert ignore into journalissuearticles values(Path 188, Row 057);. The atmospherically corrected reflectance was used for the classification of 4 land cover insert ignore into journalissuearticles values(LC); types at each site. The emissivity insert ignore into journalissuearticles values(ε); for each site is estimated by using standard values for determined LC from Look Up Table insert ignore into journalissuearticles values(LUT);. The surface-leaving radiance insert ignore into journalissuearticles values(Lλ); is computed from the atmospherically corrected thermal band 6 insert ignore into journalissuearticles values(High gain); and the emissivity insert ignore into journalissuearticles values(ε); values. The Planck equation was inverted using Landsat calibration constants to derive LST. Geospatial analysis of LST results using ArcGIS show 6 ranges of LST values for all sites. For both sensors LST retrieved for the flare stack sources are the highest values compared to other locations within the sites. Wind directions and wind speeds for Landsat data acquisitions dates and the South prevailing wind were applied to the LST for assessing their effects on it. The results show that for Eleme I and II, and Onne, the p-values results showed that no statistically significant relationships between δLST values in different directions insert ignore into journalissuearticles values(δLSTNE, δLSTNS and δLSTNW); existed. For Obigbo site, the wind direction insert ignore into journalissuearticles values(South); for data acquisition date combined with the South prevailing wind to generate a noticeable impact on the LST towards the North-East and the North-West directions. For Alua, Bonny, Chokocho, Rukpokwu, Umurolu and Sara sites, the p-value obtained is statistically significant for all the 3 insert ignore into journalissuearticles values(δLSTNE, δLSTNS and δLSTNW); relationships; therefore, producing a circle flare δLST footprint. For Umudioga site, only δLSTN versus δLSTW is statistically significant, causing a noticeable effect on the flare δLST in the North-West direction. Based on these results, it can be concluded that the volume and rate of burning gas, and the speed of the South wind at the time of satellite overpass are major factors that determine the influence of the South prevailing wind on the LST retrieved at the flaring sites in the Niger Delta.
Keywords : Investigation, prevailing, wind, land surface temperature, gas flaring, Niger Delta