Download CAMS Radiation Volume over MSG field of view

Download CAMS Radiation gridded dataset over Meteosat and Himawari fields of view

You may download this dataset from Copernicus Atmospheric Data Store at https://ads.atmosphere.copernicus.eu/datasets/cams-gridded-solar-radiation.

If this link is out of order, a mirror is available at https://www.soda-is.com/pub/files/cams/CAMS-MSG-HIMAWARI-v4.6rev2.

Copyright: please refer to this volume as "CAMS radiation service gridded dataset 4.6 rev2 over Meteosat and Himawari fields of view, computed with McClear version 3.5 and CAMS radiation v4.6".

Version

Version 4.6 rev2 is available since January 2025.

Changes since version 4.6 (July 2024):

  • Addition of Himawari field of view (South-East Asia and Oceania)

Changes since version 4.5 (July 2023):

  • Addition of 2023 radiation data
  • Addition of Northern Europe region (60 to 66 deg north)
  • Improved file compression
  • Bug fixes
  • WARNING: the way to read radiation data changed since version 4.5. See details below.

Click on the image to magnify: average GHI map over Meteosat and Himawari fields of view
Introduction
  • Temporal period: 2005 to 2023
  • Time step: 15 minute
  • Format: NetCDF
  • 1 NetCDF file per month and per component
  • Radiation components:
    • Global Horizontal Irradiation (GHI): v4.6_ghi_YYYY_MM.nc
    • Beam (direct) Horizontal Irradiation (BHI): v4.6_bhi_YYYY_MM.nc
    • Diffuse Horizontal Irradiation (DHI): v4.6_dhi_YYYY_MM.nc
    • Beam (Direct) Normal Irradiation (BNI): v4.6_bni_YYYY_MM.nc
    • Global Horizontal Irradiation in clear sky conditions (Gc): v4.6_gc_YYYY_MM.nc
    • Beam (direct) Horizontal Irradiation in clear sky conditions (Bc): v4.6_bc_YYYY_MM.nc
    • Diffuse Horizontal Irradiation in clear sky conditions (Dc): v4.6_dc_YYYY_MM.nc
    • Beam (Direct) Normal Irradiation in clear sky conditions (BNc): v4.6_bnc_YYYY_MM.nc
Grid description

We used a grid of nb_columns*nb_lines = 3600*1800 points over the whole world with a 0.1° step.

Grid:

  • grid_step = 0.1°
  • minimum longitude: -180°
  • maximum longitude: 180°
  • minimum latitude: -90°
  • maximum latitude: 90°

NB: the formula to convert (lat, lon) into grid cell is:

  • x = round((lon - lon_min)/grid_step + 0.5)
  • y = round((lat_max - lat)/grid_step + 0.5)

NB: Only grid cells on land or close to sea shore were computed. Only grid cells in Meteosat and Himawari fields of view were computed:

  • longitude range: -66° to 66° (Meteosat) and 75° to 180° (Himawari)
  • latitude range: -66° to 66°
Volume content

Each NetCDF dataset comprises up to 2976 maps, which correspond to the number of 15 min periods in 1 month.

Each value in NetCDF files contains 15 min irradiation in Wh/m². The value NaN denotes a grid cell over the sea or out of MSG field of view (not computed) or a computation error.

WARNING: Data are compressed in NetCDF files. In version 4.5, end users had to convert 254 and 255 values to NaN, and to multiply the other values by 1.2. In version 4.6, this is done automatically by NetCDF library.

Note:
If you extract NetCDF data as a time series for one cell center, you will get almost the same data as the web service CAMS Radiation web interface.
For example, CAMS_Radiation_GHI_at_point_300_on_2005-01-10.jpg compares CAMS Radiation GHI on 2005-01-10 at location (57.4, -2.4) extracted from the web service and from v4.6_ghi_2005_01.nc. The small difference is due to the data compression in NetCDF files.

Example of CAMS Radiation GHI map over MSG field of view
Click on the image to magnify: GHI on 2016-05-02 from 4h45 to 5h00 UT
Routines to read the dataset