Spatio-temporal dynamics of methane concentration and its association to climatic and vegetation parameters: a case study of the Northern Cape Province, South Africa

Abstract

Methane (CH 4 ) is the second most abundant anthropogenic greenhouse gas after carbon dioxide (CO 2 ), accounting for about 20% of global emissions. CH 4 anthropogenic emission sources include landfills, oil and natural gas systems, agricultural activities, coal mining, stationary and mobile combustion, wastewater treatment and certain industrial processes. In this work, we examine the spatiotemporal dynamics of CH 4 and its relationship to climatic and vegetation parameters in the Northern Cape province in South Africa. Various datasets from the TROPOspheric Monitoring Instrument, Moderate Resolution Imaging Spectroradiometer, Atmospheric Infrared Sounder and the Global Precipitation Climatology Project were used. The results show an increasing trend of CH 4 concentration throughout the entire province. The greatest increase in CH 4 concentration is observed in the western parts of the province during June-July-August (JJA) season. CH 4 concentration shows negligible correlation with most climatic parameters, i.e. Temperature (Temp), Precipitation (Precip) and NDVI for both seasons. The Temp-NDVI relationship shows high correlation values of r -0.71 and r 0.82 for the DJF and JJA seasons, respectively. Seasonality plays a critical role in the relationships of the CH 4 to climatic and vegetation parameters. This study shows that we are in a crisis, and robust mitigation strategies are needed to combat this.