Estimation of methane emission from rice fields using satellite data in Thiruvarur district

Abstract

Climate change is one of the most pressing modern day environmental issues. Agricultural activities are associated with the emission of greenhouse gases, notably methane (CH4) and nitrous oxide (N2O), which are important for anthropogenically influenced climate change. Among all of atmospheric components, methane (CH4) is a major greenhouse gases (GHG).Rice cultivation has been recognized as one of the major anthropogenic source for CH4 emissions. A rule-based classification approach and parameter selection approach is available for rice mapping in which the rules and parameters are derived from agronomic knowledge of the rice crop and its management. SAR-based operational mapping of rice crop across a diverse range of environments is possible with the increasing availability multi temporal Sentinel 1A satellite data at VH polarisation with 20 m spatial resolution was acquired and processed using MAPscape-RICE software. Precise estimation of methane emission from rice fields at regional scale depends on accurate assessment of rice area and the corresponding time of flooding in those fields with IPCC emission factor were used for spatial estimation of methane emission from Thiruvarur district. The total rice area in Thiruvarur district was 135237 ha during samba season 2017-18.The rate of methane emission based on IPCC factor ranged from 35.88 to 41.49 kg/ha for a period of 80 to 108 days of flooding. The total methane emission from Thiruvarur district was 1.32Gg during Samba season 2017-18.