The TANSO-FTS instrument on-board GOSAT satellite features high optical throughput, fine spectral resolution, and a wide spectral coverage (from VIS to TIR in four bands). The reflective radiative energy is covered by the VIS and SWIR (Shortwave Infrared) ranges, while the emissive portion of radiation from Earth's surface and the atmosphere is covered by the MWIR (Midwave Infrared) and TIR (Thermal Infrared) ranges. These spectra include the absorption lines of greenhouse gases such as carbon dioxide (CO2) and methane (CH4).
The TANSO-CAI instrument on-board GOSAT satellite is a radiometer in the spectral ranges of ultraviolet (UV), visible, and SWIR to correct cloud and aerosol interference. The imager has continuous spatial coverage, a wider field of view, and higher spatial resolution than the FTS in order to detect the aerosol spatial distribution and cloud coverage. Using the multispectral bands, the spectral characteristics of the aerosol scattering can be retrieved together with optical thickness. In addition, the UV-band range observations provide the aerosol data over land. With the FTS spectra, imager data, and the retrieval algorithm to remove cloud and aerosol contamination, the column density of the gases can be the column density of the gases can be retrieved with an accuracy of 1%.
The full ESA archive and newly acquired/systematically processed GOSAT FTS and CAI products are available in the following processing levels:
- FTS Observation mode 1 L1B, day
- FTS Observation mode 1 L1B, night
- FTS Special Observation L1B, day
- FTS Special Observation L1B, night
- FTS L2 CO2 profile, TIR
- FTS L2 CH4 profile, TIR
- FTS L2 CH4 column amount, SWIR
- FTS L2 CO2 column amount, SWIR
- FTS L3 global CO2 distribution, SWIR
- FTS L3 global CH4 distribution, SWIR
- CAI L1B data• CAI L1B+
- CAI L2 cloud flag
- CAI L3 global reflect. distrib. clear sky
- CAI L3 global radiance distrib. all pixels
- CAI L3 global NDVI
All products are made available as soon as processed and received from JAXA.
To satisfy NRT requirements, ESA also provides access to the FTS L1X products, which are the NRT version of FTS L1B products. The main difference between L1X and L1B is that L1X does not include CAM data, best-estimate pointing-location, and target point classification, but most of all the L1X products are available on the ESA server between 2 and 5 hours after acquisition. The L1X products remains on the FTP server for 5 days, the time for the corresponding L1B to be available. A document describing the differences between L1X and L1B products is listed in the available resources.
For more details on products, please refer to below product specifications.