[A-AS11] 大気化学

[AAS11-P22] SCALE Simulation of Fine-Grid Spatio-Temporal CO₂ Distribution Over the Kanto Region

*Tikemani Bag¹、Naoko Saitoh¹、Yousuke Sato² (1.Center for Environmental Remote Sensing, Chiba University, Japan、2.Faculty of Science, Hokkaido University, Japan)

キーワード：CO2concentration and emission, SCALE Simulation, Fine grid, Kanto region

Carbon Dioxide (CO₂), a major greenhouse gas, plays a crucial role in altering the Earth's radiative balance. As one of the primary drivers of climate change, its concentration has risen by approximately 47% due to human activities since the onset of the industrial era (IPCC, 2023). The rising concentration of CO₂ has sparked global concern, as it is a key contributor to global warming. Understanding the spatial and temporal distribution of CO₂ at a regional scale remains a critical challenge in climate change research. This knowledge is essential for assessing and mitigating the impacts of global warming. This study has investigated the spatio-temporal variation (including the diurnal and seasonal changes) of CO₂ emission and quantify the factors contributing to surface air CO₂ over Kanto region, Japan, by utilizing a newly developed CO₂ component for SCALE (Scalable Computing for Advanced Library and Environment; Nishizawa et al., 2015, Sato et al., 2015, 2024) in fine horizontal grid resolution. It is noted that Sato et al. (2024) have reported the validity of the CO₂ component for the simulation of August, 2016, but the validity of other months has never examined. Whole period of the year 2016 along with its validation are considered in the present study. The CO₂ component is formulated by assessing the emissions along with the surface-level sinks and sources, incorporating both ecosystem respiration and photosynthesis. The emissions data are obtained from the CO₂ emission inventories (Kannari et al. 2007), whereas, the Biosphere model integrating Ecophysiological and Mechanistic Approaches using Satellite data (BEAMS; Sasai et al., 2005, Wang et al., 2021)-diurnal model is utilized to estimate CO₂ sinks and sources from local vegetated areas which accurately considers the carbon exchange dynamics. We validate modeled CO₂ concentrations and its daily variations by the ground-based and aircraft measurements; they show good agreements with the observations. Present study shows that regional models with fine grid resolution allow for the simulation of various CO₂-related processes at a city scale, which is essential for refining anthropogenic emissions from urban areas.




References:

IPCC (Intergovernmental Panel on Climate Change, 2023)

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Sato, Y., et al.(2015), Impacts of cloud microphysics on trade wind cumulus: which cloud microphysics processes contribute to the diversity in a large eddy simulation? Prog. Earth Planet. Sci.,2, 23

Sato, Y., et al. (2024), High-resolution simulation analysis of factors contributing to surface CO₂ over Central Tokyo Metropolitan Area, under review, Env. Res. Lett.

Kannari A, et al. (2007), Development of multiple-species resolution hourly basis emissions inventory for Japan. Atmos. Environ. 41 3428–3439

Sasai, T., et al.(2005), Simulating terrestrial carbon fluxes using the new biosphere model “biosphere model integrating eco-physiological and mechanistic approaches using satellite data” (BEAMS), J. Geophys. Res. Biogeosci., 110, G02014.

Wang, Q., et al.(2021), Sub-daily natural CO₂ flux simulation based on satellite data: diurnal and seasonal pattern comparisons to anthropogenic CO₂ emissions in the Greater Tokyo Area, Rem. Sens., 13, 2037