Methane Interannual Distribution over Peninsular Malaysia from Atmospheric Infrared Sounder Data: 2003-2009

Received: February 16, 2012
Revised: June 5, 2012
Accepted: June 5, 2012
Download Citation: RIS|BibTeX|https://doi.org/10.4209/aaqr.2012.02.0039  

Cite this article:
Rajab, J.M., MatJafri, M. and Lim, H. (2012). Methane Interannual Distribution over Peninsular Malaysia from Atmospheric Infrared Sounder Data: 2003–2009. Aerosol Air Qual. Res. 12: 1459-1466. https://doi.org/10.4209/aaqr.2012.02.0039

ABSTRACT

Methane (CH₄) is a significant greenhouse gas (GHG's) with a relatively short atmospheric lifetime of about 12 years, and is released to the atmosphere by biological processes occurring in anaerobic environments. The CH₄ is second in importance only to CO₂ with regard to its environmental effects, and its relative global warming ability is 23 times that of CO₂ over a time horizon of 100 years. The interannual distribution of atmospheric CH₄ has been studied in Peninsular Malaysia during the period 2003–2009 using Atmosphere Infrared Sounder (AIRS) data, onboard NASA's Aqua Satellite. The analysis of CH₄ above five dispersed stations in the study area shows that the high CH₄ growth rates observed at the end of each year can be attributed to the increased emissions from biomass burning and wetlands, and the reduced hydroxyl (OH) sink. In particular, we observe a quasi-biennial variation in CH₄ emissions in Peninsular Malaysia, with varying magnitudes in peak emissions occurring in 2004, 2006, and 2008. The seasonal variation in the CH₄ fluctuated significantly between northeast (NEM) and southwest (SWM) monsoon seasons. The CH₄ value in the NEM season was higher than in the SWM season, and higher in the north regions, above the latitude 4°, than in the rest of area throughout the year. To study the CH₄ distribution over peninsular Malaysia for 2009, monthly CH₄ maps were generated using the Kriging interpolation technique. The AIRS data and satellite measurements are able to measure the increase in the atmospheric CH₄ concentrations over different regions.

Keywords: CH4; AIRS; AMSU; Peninsular Malaysia