[A-CG35] Global Carbon Cycle Observation and Analysis

[ACG35-P06] Diurnal and Seasonal Net Ecosystem Exchange in the Kantō and Chūbu Region of Japan Calculated by BEAMS-diurnal Model

*Qiao Wang¹, Ryoichi Imasu¹, Yutaka Arai¹, Yasuko Mizoguchi² (1.Atmosphere and Ocean Research Institute, The University of Tokyo, 2.Hokkaido Research Center, Forestry and Forest Products Research Institute)

Keywords:Diurnal cycle, Seasonal variations, Gross Primary Production, Respiration

Cities emit 50% – 80% of the global total anthropogenic CO₂ emissions. Terrestrial ecosystems (forests, grasslands, and croplands) in and around cities induce biogenic CO₂ fluxes via photosynthesis, autotrophic and heterotrophic respiration, such fluxes complicate the characterizing of CO₂ concentration diurnally and seasonally. We developed a diurnal version of BEAMS model (Sasai et al., 2005; 2012; and 2016) to calculate Gross Primary Production (GPP) and Ecosystem Respiration (R_e). The objective of this model development is for future model coupling with regional transport models to analyze changes of CO₂ concentration over urban area. In this study, we modeled hourly GPP and R_e in the Kantō and Chūbu Region of Japan during the period of 2015 – 2021. We summed our hourly GPP results to 8-day average for comparison with satellite-based GPP products, such as Moderate Resolution Imaging Spectroradiometer (MODIS) Terra/Aqua GPP, Global Land Surface Satellite (GLASS) GPP, Global OCO-2 Solar-Induced Chlorophyll Fluorescence (GOSIF) GPP, and Global Moderate Resolution Dataset of Gross Primary Production of Vegetation for 2000–2019. We also aggregated our hourly Net Ecosystem Exchange (NEE = R_e – GPP) results to daily scale for comparison with Soil Moisture Active Passive (SMAP) L4 daily NEE data. By replacing or expanding the target area of input climate and vegetation structure datasets, BEAMS-diurnal is applicable to model the distribution of NEE at regional scale or global scale.