Spatial and Temporal Variability of Atmospheric Methane Concentrations in Bangladesh

We used 2019-2021 TROPOMI satellite observations of atmospheric methane in an analytical inversion to identify methane (CH4) emissions in Bangladesh from 2019 to 2021. Methane is considered as second most important greenhouse gas (GHG) contributor, with nearly 28 times more potential to global climate change next to carbon dioxide. Monitoring and predicting atmospheric methane concentrations is important in global efforts to mitigate and adapt to climate change. This study made an effort to detect existing concentrations of CH4 at the atmospheric level of Bangladesh, hot spot identification, and spatial-temporal pattern detection using remote sensing. The study used daily column-averaged dry air column methane mixing ratio (XCH4) data retrieved from TROPOMI measurements. Weekly/monthly average concentrations were extracted from Sentiniel-5P satellite images. The batch inverse Distance weighting (IDW) interpolation technique was conducted on raw images (excluding October months) to fill in missing values in the images. The emerging hot spot analysis tool (ArcGIS Pro) was applied to the weekly interpolated images to identify statistically significant spatiotemporal hotspots of CH4 concentrations. Results indicate that the persistent hot spot and intensifying hot spot of methane concentrations are prominent within the Dhaka Division. An intensifying hot spot of CH4 was found within the Dhaka district, which indicates that it is a hot spot for the study period. Source point detection and real-time monitoring can be more effective in identifying the methane emission reduction mechanism.