About the ACCESS model

The Australian Community Climate and Earth-System Simulator (ACCESS) weather models have been developed and tested by staff from the Bureau's Research and Research to Operations Branches and are based on the UK Meteorological Office's Unified Model. ACCESS output is available in map form or as gridded data products. ACCESS output is available in map form or as gridded data products.

Model ACCESS-G (deterministic) and GE (ensemble)
Version APS3
Domain Global
Resolution Approximately 12.5 km (G) and 33 km (GE)
Time Step and Duration 6 hourly to 240 hours (10 days)
Model Run Times and Typical Availability Times 00Z run available 0645Z
12Z run available 1845Z
Views Global
Southern Hemisphere
Australia
Indian Ocean
Pacific Ocean
Available Elements Mean sea level pressure (MSLP) & rainfall
Surface winds
MSLP & thickness
Wind speed and direction at 10m, 850hPa, 700hPa, 500hPa, 200hPa, and gradient
Geopotential height at 850hPa, 700hPa, 500hPa, and 200hPa
Temperature at 2m screen, 850hPa, 700hPa, 500hPa, 200hPa
2m screen dew point
Relative humidity at 2m screen, 850hPa, 700hPa, 500hPa, and 200hPa
Other fields available as gridded data
Model ACCESS-C (deterministic) and CE (ensemble)
Version APS3
Domain
City Region:
Victoria/Tasmania
New South Wales
Queensland
South Australia
Western Australia
Northern Territory
North Queensland
Resolution Approximately 1.5 km (C) and 2.2 km (CE)
Time Step and Duration 3 hourly to 36 hours (forecast)
1 hourly to 42 hours (analysis)
Model Run Times and Typical Availability Times 00Z run available 0325Z
06Z run available 0935Z
12Z run available 1525Z
18Z run available 2125Z

N.B. All runs available one hour earlier during the daylight saving period.
Views Not applicable
Available Elements Available as gridded data only.
Model ACCESS-TC
Version APS3
Domain Relocatable 33°x33° grid domain
Resolution 0.036° (~4km)
Time Step and Duration 1 hourly to 72 hours (3 days)
Model Run Times and Typical Availability Times Run on demand
Views Not applicable
Available Elements Available as gridded data only

Upper air charts are generally labelled with the pressure level in hectopascals (hPa), e.g. 500 hPa. The pressure decreases as altitude increases. For instance, the 250 hPa level is higher than the 500 hPa level. For some fields there are also charts representing the atmosphere 2 metres and 10 metres above the ground, and at the "gradient" level which lies about 1000 metres above the earth's surface and is the level most representative of the air flow in the lower atmosphere immediately above the layer affected by surface friction. This level is free of local wind and topographic effects (such as sea breezes, downslope winds etc).

Some charts show geopotential height, which approximates the actual height of a pressure surface above mean sea-level. Therefore, geopotential height contours on a particular map, e.g. 850 hPa, represent the height of that pressure surface.

Charts showing precipitation represent the amount of rainfall in millimetres which is forecast to fall at the ground over the preceding 3 or 6 hours. The period is shown in the chart heading as "3 hrly" or "6 hrly".

For more details about ACCESS see the Analysis and Prediction Operations Bulletins.

Users interested in accessing raw data via FTP should refer to the ACCESS NWP Data Documentation.