A hyper-temporal monitoring of terrestrial gross primary productivity and evapotranspiration across Asia-Oceania using third generation geostationary satellites, Himawari-8/9

Evapotranspiration (ET) and Gross Primary Productivity (GPP) are fundamental variables on land surfaces, and are important for understanding the response of vegetation and land surfaces to extreme weather. In particular, third-generation geostationary meteorological satellites such as Himawari-8/9 are effective for land monitoring, as they include observations of wavelength bands including visible and near-infrared light every 10 minutes. In addition, if geostationary meteorological satellites are used, monitoring with high temporal resolution such as 30 minutes can be done in quasi-real time. In this study, we attempted to monitor GPP and ET in the Asia-Oceania region using data from geostationary meteorological satellites, Himawari-8 and 9. We used the EC-LUE model for GPP and the PT-JPL model for ET, and verified the results using flux observation sites in Asia and Oceania. We also used data from Himawari-8/9, including solar radiation, surface temperature, surface reflectance, and albedo. This method can estimate GPP and ET in the Asia-Oceania region every 30 minutes, and it can reproduce observation well. In addition, the spatial outputs can be used to monitor vegetation changes during heat waves and dry events. Although each geostationary satellite observes a fixed hemisphere, combining data from multiple geostationary satellites can be used to develop high-frequency global observations.