Satellite Derived Global Solar Radiation

About Global Solar Radiation | Daily Solar Radiation Map | Solar Radiation Browse Service

The accuracy of the model's daily estimates of insolation is estimated by comparison with independent measurement by Bureau ground instruments. These solar exposure values, derived from images from the GOES-9 satellite, are of slightly lower quality than those that were available here prior to 22 May 2003, which were derived from the GMS-5 satellite. This is due to the difference in location of GOES-9 and the different characteristics of its imager, compared to GMS-5, and to noise in the GOES-9 visible channel images that is generated within the satellite. An assessment against Bureau surface measurements indicated that the GOES-9 product initially tended to overestimate daily exposure by an amount that increased with cloudiness. From 21 May 2004 an updated satellite calibration has been used, which is expected to reduce the bias but the effect has not yet been assessed.

The average error (bias, in the sense of satellite estimate minus surface measurement) in the initial year of production from GOES-9 was up to around ±2 megajoules per square metre in clear conditions, and up to +5 MJ per square metre under heavy cloud outside the tropics and up to +12 MJ per square metre under heavy cloud in the tropics. The error had an additional scatter of up to around ±2 MJ per square metre (standard deviation) around this bias.

The Bureau expects to be able to improve the accuracy of the satellite exposure estimates as the GOES-9 characteristics become better understood and processing systems are improved, and users will be advised on this website of improvements.

A table of historical solar exposure errors is availabe here.

Solar radiation information has a number of meteorological, agricultural and engineering applications. This information is available from the Bureau of Meteorology as estimates derived from satellite data . The estimates are daily solar exposure values in megajoules per square metre (this is a measure of daily incoming solar energy).

These registered user services are provided on a cost recovery basis and billed through subscription charging. Information on conditions of use is provided under copyright information.

Historical Data

A solar radiation browse service provides free access to historical Australian Region maps back to November 1998.

Real-time Data

1. Colour maps of daily global solar exposure over Australia (last 7 days)
2. Grid files of daily global solar exposure values over Australia (last 7 days)
3. Tables of daily global solar exposure values at selected sites in Australia (last 7 days)
4. Get global solar exposure values at arbitrary site in Australia (last 7 days)

The products provided are derived from satellite data and may have small errors. They have an accuracy better than 10% on average (more information).

The map above is an example of the daily global solar exposure map. It represents estimates of the insolation or daily global exposure that reaches the earth's surface, in this case on 7th February 1998.

Acknowledgements
The original satellite data used by the Bureau of Meteorology to derive the solar radiation estimates comes from the Geostationary Meterological Satellite (GOES-9). GOES-9 is operated by the joint effort of the Japan Meterological Agency and the United States' NOAA NESDIS. Any use of the solar radiation estimates requires acknowledgement of both the Japan Meterological Agency (JMA) and NOAA NESDIS as the original source of the raw satellite data, and acknowledgement of the Commonwealth of Australia (Bureau of Meteorology) which received the GMS imagery, and processed it using its sophisticated computer model for solar radiation.