Access Gridded Data

Gridded data are available for a range of variables in NetCDF and GeoTiff formats. The NetCDF datasets are arranged in annual blocks where each file contains all of the grids for the selected year and variable. The GeoTiff datasets are not arranged in blocks; each file contains a single grid for the selected day (or month in the case of monthly rainfall) and variable.

Please note SILO also provides point datasets. Temporal (point) data at individual grid locations can be downloaded using our web interface or web API.

SILO's gridded datasets are hosted on Amazon Web Services under the AWS Public Data Program.

How can I access the data?

Annual NetCDF files:

Data Source(s)*

Each annual NetCDF file (for daily variables) is approximately 410 MB in size. The annual NetCDF files for monthly rainfall are smaller (14 MB) because they only contain 12 monthly grids, instead of 365 or 366 daily grids.

Daily / Monthly GeoTiff files:

Data source(s)*

To ensure you obtain the most recent version of the selected dataset, please clear your browser cache before downloading.

Gridded data are available for:

  • Mean sea level pressure: 1957 - current year
  • Evaporation - Class A pan: 1970 - current year
  • All other variables: 1889 - current year

How else can I access the data?

The gridded data are stored on Amazon S3The NetCDF data are arranged in a directory structure of the form annual/<variable>/<year>.<variable>.nc where variable is the variable's short name. Similarly, the GeoTiff data are arranged in a directory structure of the form daily/<variable>/<year>/<year><month><day>.<variable>.tif (daily variables), and monthly/<variable>/<year>/<year><month>.<variable>.tif (monthly variables)The datasets can be accessed by the following methods:

  • Using the AWS command line interface:
    For example, the 2005 data for monthly rainfall can be downloaded in NetCDF format as follows:
    aws s3 cp s3://silo-open-data/annual/monthly_rain/ .

    Alternatively, all monthly rainfall files can be downloaded in NetCDF format as follows:
    aws s3 sync s3://silo-open-data/annual/monthly_rain/ .

    As another example, the daily maximum temperature dataset for 3 Jan 2018 can be downloaded in GeoTiff format as follows:
    aws s3 cp s3://silo-open-data/daily/max_temp/2018/20180103.max_temp.tif .

  • Direct access via URL:
    Datasets can be downloaded via URL using a web browser, scripting APIs (such as netCDF4-python for Python) or command line tools such as curl or wget. The URL has the form:<variable>/<year>.<variable>.nc

    For example, the 2015 data for class A pan evaporation can be downloaded using curl as follows:
     curl "" --remote-name

How can I access interpolation logs?

Detailed log files describing the observational data used to construct each gridded raster are stored on Amazon S3. The log files are arranged in a directory structure of the form interpolation-logs/<variable>/<year>/<date>.<variable>.log where variable is the variable's short name and date is the date in yyyymmdd format (or yyyymm for monthly variables). The log files can be accessed using either the AWS command line or direct access methods described above.

How can I interact with the NetCDF gridded data?

Use the tools and examples provided below to get started.


The example shows how to import a NetCDF dataset and analyse.

Read more
NetCDF Operators

The example shows how NCO tools can be used to process NetCDF datasets.

Read more
Convert NetCDF files

The example shows how NetCDF files can be converted to other formats.

Read more

Last updated: 3 June 2021