RECENT RESULTS FROM EO STUDIES ON INDIAN CARBON CYCLE ASSESSMENT

摘要

The monsoon based climate system, diverse land use and land cover distribution and cultural practices poses complex issues in monitoring, assessment and simulation of Indian carbon cycle. Several studies reported lack of spatially and temporally consist ent databases, need for calibration and validation of models, and development of national frame work to maintain consistency and completeness in efforts and reduction of uncertainty. Considering the need, as part of ISRO Geosphere Biosphere Programme, Nati onal Carbon Project (NCP) initiative was taken up to understand and assess land, atmosphere and oceanic components of carbon cycle with a significant scope for integration of remote sensing, geospatial and process based models. The results from the initial studies are discussed in the paper. An increase of the country’s forest carbon stocks from 6244.8 to 6621.6 Mt with an annual increment of 37.7 Mt of the carbon from 1995 to 2005 is reported. In the national scale, CASA model based average a nnual NPP is estimated to be 1.5 Pg C Yr~(-1) and is increasing at the rate of 0.005 Pg C Yr~(-2) during past 25 years from 1981-2006. Analysis of Mid tropospheric CO_2 levels retrieved from AIRS data since 2002 till now revealed increasing rate of CO_2 at 2.14 ppmv yr~(-1). It was also o found that biosphere uptake over India and oceanic uptake over the south Indian Ocean could play positive role on the control of seasonal variability of atmospheric carbon dioxide growth rate The paper presents further details on different sub components, recent results and challenges ahead of the project.