Initial Development of Himawari-8 Aerosol Product in JAXA

The new Japanese geostationary meteorological satellite Himawari-8 was developed by Japan Meteorological Agency and was launched from JAXA Tanegashima Space Center on 7th October 2014. Himawari-8 loads a visible infrared radiometer, Advanced Himawari Imager (AHI). The most advanced aspect of AHI is its high observation frequency: it observes the full-disk image over Asia and Oceania region every 10 minutes and even 2.5 minutes for the regions around Japan. Comparing with the previous Himawari-6/7 satellite, the number of channels increased from 5 to 16 channels; for channels that observes aerosols, there was only 0.64 µm channel on Himawari-6/7 whereas the Himawari-8 equips 0.47 µm, 0.51 µm and 0.64 µm channels. The observation resolution in the visible channel also increased from 1km to 0.5km. Taking the advantage of its high temporal and spatial resolution, the new AHI is expected to provide highly accurate aerosol dataset and to deepen our understanding on the aerosol in the earth.

Earth Observation Research Center (EORC) of Japan Aerospace Exploration Agency (JAXA) is developing the aerosol product retrieved from AHI data. The retrieval algorithm is same as that developed for the upcoming earth observation satellite, Global Change Observation Mission - Climate (GCOM-C), which is based on the schemes by Higurashi and Nakajima (1999, 2002) over land and Fukuda et al. (2013) over ocean. In order to apply the algorithm to AHI, we used its 0.51µm and 0.64 µm channels for land and 0.64 µm 0.86 µm channels for ocean. Using the response function of AHI, we constructed the look-up-tables by the radiation transfer package of STAR series (Nakajima and Tanaka 1986, 1999; Ota et al. 2009). The clear sky pixels were selected by using the CLAUDIA algorithm (Ishida and Nakajima 2009; Ishida et al. 2011) which was developed for GOSAT/CAI, GCOM-C/SGLI and EarthCARE/MSI.

The JAXA Himawari-8 aerosol product is expected to be disseminated with the L1b reflectance/radiance product in netCDF every one hour. After a simple user registration, users will be able to download the dataset freely from JAXA/EORC Homepage.