Data Sources

WeatherLayers GL can be used either with custom self-hosted data or with WeatherLayers Cloud.

For integrating any custom data (NetCDF, GRIB), the data needs to be transformed by your backend server to a supported data type, data format and map projection.

Data sources

• WeatherLayers Cloud public data sources - NOAA (GFS, GFS Wave), Copernicus (CMEMS, CAMS)

• other public data sources - ECMWF, ICON, Copernicus (ERA5), ...

• commercial data sources

• custom data sources - your own data from scientific research

Supported data types

• Uint8

  • quantized data into 256 possible values

  • lower precision, higher compression ratio for lower file size

  • recommended for visualization purposes

  • original data bounds need to be provided to unscale the data into the original data, see Data Properties imageUnscale

• Float32

  • original data

  • better precision, lower compression ratio and larger file size

  • recommended for scientific purposes, or for use cases where exact values with no quantization errors are needed

Supported data formats

• PNG, WebP (Uint8)

  • scalar - R channel

    • nodata - 0 in A channel

  • vector - RG channels

    • nodata - 0 in A channel

• GeoTIFF (Uint8)

  • scalar - band 1

    • nodata - 0 in band 2

  • vector - bands 1 and 2

    • nodata - 0 in band 4

• GeoTIFF (Float32)

  • scalar - band 1

    • nodata - NaN in band 1

  • vector - bands 1 and 2

    • nodata - NaN in bands 1 and 2

Supported projections

• equirectangular projection (EPSG:4326)

Data transformation

Data transformation into a supported format can be done on your servers with GDAL.

See gdal_translate for transformations between data types and data formats.

See gdalwarp for transformations between map projections.

See gdal_calc for calculations and gdalbuildvrt for merging files.

Example – Temperature from GRIB to PNG

Scale from [213.15, 325.15] to [0, 255], disable GDAL unit normalization from K to C:

gdal_translate -ot Byte -scale 213.15 325.15 0 255 --config GRIB_NORMALIZE_UNITS=NO temperature.grib temperature.png

WeatherLayers GL configuration:

• imageType: WeatherLayers.ImageType.SCALAR

• imageUnscale: [213.15, 325.15]

Example – Wind from GRIB to PNG

Calculate vector magnitude:

gdal_calc --calc='sqrt(A * A + B * B)' -A wind_u.grib --A_band=1 -B wind_v.grib --B_band=1 --outfile wind_magnitude.tif

Merge files:

gdalbuildvrt -separate wind.vrt wind_magnitude.tif wind_u.grib wind_v.grib

Scale from [-128, 127] to [0, 255]:

gdal_translate -ot Byte -scale -128 127 0 255 wind.vrt wind.png

WeatherLayers GL configuration:

• imageType: WeatherLayers.ImageType.VECTOR

• imageUnscale: [-128, 127]