Temporal and spatial distribution of the mid-tropospheric CO2 concentrations in Malaysia

Abstract

Satellite observations of CO2 offer a unique opportunities to improve our understanding of the carbon sources and sinks. Due to the lack of studies of carbon dioxide (CO2) concentration in this region, we first confirmed the reliability of the mid-tropospheric Atmospheric Infrared Sounder (AIRS) CO2 data using atmospheric CO2 concentration data from the only available Global Atmospheric Watch (GAW) ground-based station observation in Malaysia. In this study, the spatial and temporal distribution of mid-troposphere CO2 in Malaysia from January 2009 to December 2012 was analyzed based on AIRS satellite product. The results show that the average CO2 concentrations were high in the eastern part of the study area and lower in the west. From January 2009 to December 2012, the mid-tropospheric CO2 concentrations increased gradually with annual growth rate about 1.293 ppmv/a. There was a significant seasonal CO2 variation with peak concentration was observed during the North-East monsoon (NEM) and the lowest was during South-West monsoon (SWM). The temporal distribution of CO2 concentrations was mainly affected by the amount of sunlight and precipitation received during both monsoons. The study suggested that mid-tropospheric AIRS CO2 data product was able to help in understanding the variations of atmospheric CO2 concentrations comprehensively.