No “Clouded” Judgments From Geostationary Satellite

Environmental scientists are always in search of new tools that can better characterize the Earth’s surface. Tomoaki Miura, in the Department of Natural Resources and Environmental Management, is lead author of a new study published in Scientific Reports that shows that Himawari-8, a new-generation geostationary satellite, was able to acquire cloud-free observations every 4 days and capture the seasonal changes of vegetation more accurately than before. 

The study, “Improved Characterisation of Vegetation and Land Surface Seasonal Dynamics in Central Japan with Himawari-8 Hypertemporal Data,” explains that satellite remote sensing has widely been used to monitor and characterize the spatial and temporal changes of the Earth’s vegetative cover. Satellites used in these analyses have usually been satellites which orbit from pole to pole and obtain only one to two images of the Earth per day. And even these images may often be less useful when frequently occurring clouds block the polar-orbiting satellites’ view of the land surface.

New-generation geostationary satellites present an opportunity to observe land surfaces in a more efficient manner. The Advanced Himawari Imager (AHI) sensor onboard Himawari-8, which is in geostationary orbit, can obtain multi-band color images over Japan every 10 minutes, increasing the chance of obtaining “cloud-free” observations. 

“Detailed vegetation seasonal information from the Himawari-8 geostationary satellite can be useful for many applications such as short-term drought monitoring and assessing the impact of heavy rainfall events,” said Tomoaki. It is also expected that AHI geostationary sensor data will contribute to improving understanding of vegetation dynamics and the effect of climate change.