What is available

What data are available from SILO?

SILO provides historical daily weather records for Australia from 1889 to present. Subscriptions are available for the following products:

  • Gridded datasets: interpolated surfaces which have been derived either by splining or kriging the observational data. The grids are stored on a regular 0.05° x 0.05° grid, which is approximately 5 km x 5 km.
  • Patched Point Data: a daily time series of data at a point location consisting of station records which have been supplemented by interpolated estimates when observed data are missing. Patched datasets are available at approximately 4800 Bureau of Meteorology recording stations around Australia.
  • Data Drill: a daily time series of data at a point location consisting entirely of interpolated estimates. The data are taken from our gridded datasets and are available at any grid point over the land area of Australia (including some islands).

Data are available for seven primary variables:

  • maximum and minimum air temperature;
  • rainfall;
  • class A pan evaporation;
  • solar radiation;
  • vapour pressure; and
  • mean sea level pressure;

and nine derived variables:

  • relative humidity at the time of maximum and minimum temperature;
  • synthetic pan evaporation; and
  • evapotranspiration (six estimates - FAO561 short crop and ASCE2 tall crop estimates; and Morton’s actual, potential, wet and lake estimates3).

Patched Point and Data Drill data are available for an additional 12 derived variables:

  • vapour pressure deficit;
  • day counts (rain and frost at three threshold temperatures);
  • monthly means (maximum, minimum and weighted daily mean temperatures, solar radiation and vapour pressure); and
  • monthly totals (rainfall and evaporation).

SILO datasets are constructed from observed data where station records are available. While many of SILO's data formats include a flag indicating the source of each datum, users should note that observed data are not available for:

  • Class A pan evaporation: 1889-1969. (Long term daily averages are provided, however synthetic estimates are available); and
  • Mean Sea Level Pressure: 1889-1956. (Long term daily averages are provided).

Metadata describing the primary variables and the procedures used to construct them are available in the Queensland Spatial Catalogue.

Users should be aware that SILO data are constantly evolving:

  • Recent datasets (up to 12 months following the day of observation) grow rapidly as new observational data are added;
  • Older datasets may grow slowly as hand written (paper-based) records are digitised; and
  • All datasets may undergo minor changes as a result of error detection programs undertaken by SILO and the Bureau of Meteorology.

Clients requiring a static dataset for analysis should download and archive their own copy of the data.

 

Available formats

SILO data are available in a range of formats tailored to client needs. The Patched Point and Data Drill datasets are available in fifteen different formats. The spatial datasets are typically provided as ASCII grids, but alternative formats are available upon request.

Please contact the SILO team if you require assistance or a specialised product tailored to your requirements.

 

Footnotes

  1. Food and Agriculture Organization of the United Nations, Irrigation and drainage paper 56: Crop evapotranspiration - Guidelines for computing crop water requirements.(1998).
  2. ASCE’s Standardized Reference Evapotranspiration Equation, proceedings of the National Irrigation Symposium, Phoenix, Arizona, 2000.
  3. Morton, F. I. (1983). Operational estimates of areal evapotranspiration and their significance to the science and practice of hydrology. Journal of Hydrology, Volume 66, 1-76.
Last updated: 28 November 2017