ACCESS-G: single-level "syncld" fields
A number of raw and post-processed NWP products are available as outputs from the Australian Community Climate Earth-System Simulator (ACCESS) suite of Numerical Weather Prediction models which are run routinely by the Bureau National Operations Centre (NOC). This document describes the content of the ACCESS-G (version APS3) IDY25000.APS3.syncld.slv.YYYYMMDDHH.HHH.surface, IDY25006.APS3.syncld.slv.YYYYMMDDHH.HHH.surface, IDY25001.APS3.syncld.slv.YYYYMMDDHH.HHH.surface, IDY25020.APS3.syncld.slv.YYYYMMDDHH.HHH.surface and IDY25021.APS3.syncld.slv.YYYYMMDDHH.HHH.surface series of products.
For background information about ACCESS please refer to the top-level ACCESS NWP technical data documentation page.
If you require further information or assistance about ACCESS NWP products contact the Bureau's Real-time Data Services Section.
Model summary
ACCESS-G covers a global domain, has a resolution of about 12 km and is run four times per day (00Z, 06Z, 12Z & 18Z basetimes) out to a forecast hour (HHH) of +240 (+84 for 06Z and 18Z). This model consists of both an assimilation and forecast component.
NWP data filename convention
All NWP files in this product series have names that conform to the following convention:
IDY25000.APS3.syncld.slv.YYYYMMDDHH.HHH.surface.grb2 or
IDY25006.APS3.syncld.slv.YYYYMMDDHH.HHH.surface.grb2 or
IDY25001.APS3.syncld.slv.YYYYMMDDHH.HHH.surface.grb2 or
IDY25020.APS3.syncld.slv.YYYYMMDDHH.HHH.surface.grb2 or
IDY25021.APS3.syncld.slv.YYYYMMDDHH.HHH.surface.grb2
where
| YYYYMMDDHH | Base-date of model run in UTC time. YYYY = year, MM = month, DD = day, HH = hour |
|---|---|
| HHH | Forecast hour. A HHH of 000 is the analysis time-step. |
Horizontal grid geometries
Variant
[IDY code]
|
Resolution
[Lon x Lat]
|
Domain limits
[W to E, S to N (Lon x Lat grid points)]
|
Parameters
[NC Vars]
|
|---|---|---|---|
IDY25000
|
0.176 by 0.117 | 0.088 to 359.912, -89.941 to 89.941 (2048 x 1536) | All |
IDY25006
|
0.176 by 0.117 | 64.951 to 184.482, -64.980 to 16.934 (681 x 700) | All |
IDY25001
|
0.176 by 0.117 | 95.010 to 169.893, -54.902 to 4.980 (427 x 512) | All |
IDY25020
|
0.176 by 0.117 | 0.088 to 359.912, -89.941 to 89.941 (2048 x 1536) | All |
IDY25021
|
0.176 by 0.117 | 95.010 to 169.893, -54.902 to 4.980 (427 x 512) | All |
Please note that
- Latitude values in GRIB and NetCDF files are ordered North to South while longitude values are ordered West to East.
- Longitudes always lie in the range 0.0 to 360.0 degrees. Longitudes can be transformed to lie between -180 and +180 degrees by subtracting 360 degrees from any longitude values greater than 180.
Time steps
- Forecast hours of single-level fields:
- 0 to 117 by 3, 120 to 240 by 6
Parameters
The following fields are included in this product series. Note that the "G2 d.c.n" table column refers to a field's GRIB2 'discipline'.'parameterCategory'.'parameterNumber' metadata. For more information see GRIB2 format notes.
Single-level fields
| G2 d.c.n | NetCDF var | Steps | G2 Units | NC Units | Description |
|---|---|---|---|---|---|
| 0.5.7 | syn_ir_tbb | All | K | K | Synthetic infrared satellite brightness temperature |
| 0.5.7 | syn_wv_tbb | All | K | K | Synthetic water vapour satellite brightness temperature |
Explanation of steps column terms
| All | Parameter available at all time-steps |
|---|---|
| All but steps | Parameter available at all time-steps except as specified |
| hhh... | Parameter available from fhr onward |
Notes on specific NWP file-formats
For technical notes about the GRIB2 encoding of ACCESS data, please refer to GRIB2 format notes. For technical notes about the NetCDF4 encoding of ACCESS data, please refer to NetCDF format notes.
Appendix A - Extended Field Descriptions
Extended description of single-level fields
| G2 d.c.n | NetCDF var | Detailed description |
|---|---|---|
| 0.5.7 | syn_ir_tbb | Synthetic imagery for the 10.8 micron channel using the spectral response function for GMS-5 (similar to Himawari 8/9 band 13) using a radiative transfer model. [K] |
| 0.5.7 | syn_wv_tbb | Synthetic water vapour channel imagery for the 6.8 micron channel of MTSAT-2 (similar to Himawari 8/9 band 8) using a radiative transfer model. [K] |
Please note:
- Fields in the above tables are listed in the same order as shown in the Parameters section of this document.
- Units in the above table refer to NetCDF fields. In some cases the GRIB2 equivalent field has had values scaled/offset to convert to SI units for WMO GRIB2 compliance.
- The nature of fields can not always be deduced easily from their NetCDF variable names. It is always safest to refer to the detailed description of a parameter.