Introducing Satellite Data Based Biosphere Model BEAMS to Improve Regional Transport Model AIST-MM for Estimating Carbon Dioxide Emission from Mega-city Tokyo

Together with modelling system improvements, satellite carbon dioxide (CO2) observation developments such as GOSAT (Greenhouse gases Observing SATellite) and GOSAT-2 offer new possibilities of finer CO2 emission estimations via top-down approach, particularly, in mega-cities such as Tokyo, where the largest anthropogenic carbon source occurs. In summer, forests west and north of Tokyo Metropolis in the Kant¯o plain cause significant CO2 fluxes (photosynthesis uptake + respiration release). These land-atmosphere CO2 exchanges, however, have yet to be realistically simulated in the regional transport model AIST-MM (National Institute of Advanced Industrial Science and Technology-Mesoscale Model)[1,2]. This study plans to improve regional CO2 concentration simulations by integrating BEAMS (Biosphere model integrating Eco-physiological And Mechanistic approaches using Satellite data)[3,4] photosynthesis and respiration components, MODIS and GCOM-C (Global Change Observation Mission-Climate) satellite data to our transport model and then introduce GOSAT data to the inversion analysis for emission inventory update. We expect the optimized model to better simulate both seasonal and diurnal CO2 variations in Greater Tokyo, which have been observed from ground CO2 monitoring data[5]. References [1] Kondo, H., "A numerical experiment of the" Extended Sea Breeze" over the Kanto Plain." Journal of the Meteorological Society of Japan. Ser. II, 68(4), pp.419-434. 1990 [2] Kondo, H., Saigusa, N., Murayama, S., Yamamoto, S. and Kannari, A., "A Numerical Simulation of the Daily Variation of CO2 in the Central Part of Japan—Summer Case—." Journal of the Meteorological Society of Japan. Ser. II, 79(1), pp.11-21. 2001 [3] Sasai, T., Ichii, K., Yamaguchi, Y. and Nemani, R., "Simulating terrestrial carbon fluxes using the new biosphere model "biosphere model integrating eco-physiological and mechanistic approaches using satellite data"(BEAMS)." Journal of Geophysical Research: Biogeosciences, 110(G2). 2005 [4] Sasai, T., Saigusa, N., Nasahara, K.N., Ito, A., Hashimoto, H., Nemani, R., Hirata, R., Ichii, K., Takagi, K., Saitoh, T.M. and Ohta, T., "Satellite-driven estimation of terrestrial carbon flux over Far East Asia with 1-km grid resolution." Remote Sensing of Environment, 115(7), pp.1758-1771. 2011 [5] Imasu, R. and Tanabe, Y., "Diurnal and Seasonal Variations of Carbon Dioxide (CO2) Concentration in Urban, Suburban, and Rural Areas around Tokyo." Atmosphere, 9(10), p.367. 2018