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IR GEO-ring database

To build a Deep convective system database over the entire tropical belt for the 2012-2020 period, a homogenized procedure has been performed on the infrared observations from the fleet of multi-agencies meteorological geostationary satellites data (Fiolleau etal 2019) . Each geostationary platform of the GEO-ring enables the processing of a specific region (Eastern-Pacific, America, Africa, India, Western-Pacific).

Fleet of multi-agencies meteorological geostationary satellites used to monitor the entire tropical belt for the 2012-2020 period

The GEO-ring is far from a homogeneous suite of instruments operated in similar fashion. Spatial and temporal resolutions, as well as the spectral filter functions and the calibration procedures differ from one platform to another. All of these technical differences lead to biases in the brightness temperature measurement from one geostationary platform to another one. To overcome such issues, a homogenized procedure has been performed on the infrared geostationary observations.

Table I: Technical characteristics of the operational geostationary satellites fleet and the associated imagers used over the 2012-2020 period.

  • The temporal frequency used is set at 30 minutes for all geostationary platforms, including MSG, HIMAWARI-8, GOES-16 and GOES-17 which have an observation frequency of 15min for MSG and 10min for the others. This allows convective systems to be segmented homogeneously.
  • The inhomogeneity of the spatial resolution has been accounted for by regridding the IR data of each geostationary satellite from their native projections to a common map projection, a 0.04° equal-angle latitude/longitude grid.
  • The IR data have also been inter-calibrated and spectrally normalized by using the ScaRaB/Megha-Tropiques observations.
  • A limb adjustment has been also applied to correct the brightness temperature dependency to the viewing zenithal angle.
  • Latitudinal extension of the GEO-ring between 55°S and 55°N.

The resulting homogenized GEOring IR dataset is called GEOgrid_colcloud. The GEOgrid_colcloud dataset can be found in the following link:

CC BY 4.0 : Permission is granted to use these data in research and publications mentionning the dataset DOI and the reference articles and accompanied by the following statement: The authors acknowledge the data center ESPRI/IPSL for providing access to the data.