N Saigusa*
*Center for Global Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan


There is an increase in number of observational platforms, such as satellites, aircrafts, ships, and ground stations, for monitoring atmospheric greenhouse gases (GHGs) and their surface fluxes. National or regional inventories of GHG emissions have also been prepared at greater resolution in space and time. However, due to uncertainties in modeling tools, and limited observational data coverage, high uncertainty still remains in global or regional sources/sinks estimations.

The Center for Global Environmental Research, National Institute for Environmental Studies has been developing an integrated carbon observation and analysis systems based on satellite, airborne and ground-based observations, and atmospheric and terrestrial carbon cycle models. Atmospheric observations are greatly enhanced using GHG observing satellites and aircraft observations recently. Transport modeling, inverse modeling, and assimilation methods are being developed and improved for better utilization of observational data from the Asia-Pacific region. Global and regional surface fluxes are estimated and constrained by both "top-down” approach using inverse models and "bottom-up” approach using surface flux observation network data (e.g. AsiaFlux) and upscaling with terrestrial ecosystem models.

Current progress will be presented in better constraints of global, continental, and regional carbon budgets, and detection of carbon cycle change particularly in the Asia-Pacific. Discussions are included how to solve the following questions in the next steps: 1) How can the current capabilities of top-down and bottom-up approaches contribute to reduce uncertainties in the estimates of large anthropogenic emissions?; 2) What are the key target regions or events in the Asia-Pacific that we need to focus on? (e.g. El Niño-induced droughts, extreme forest fires in Southeast Asia, and peat degradations in tropical and boreal regions); 3) How should the current capabilities of observation, modeling and analysis systems be integrated into an operational system for long-term monitoring of changes in regional, continental, and global GHGs budgets?; and 4) How can we provide scientific knowledge and data timely for evaluating mitigation and adaptation policies?


This is based on the outcomes of a three-year project (FY2014-2016) conducted by members from National Institute for Environmental Studies (NIES), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Meteorological Research Institute (MRI), and Center for Environmental Remote Sensing, Chiba University with a financial support from the Environment Research and Technology Development Fund (No. 2-1401) by the Ministry of the Environment, Japan.


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