Regional ATOVS Retransmission Services (RARS) are operational arrangements for the real-time acquisition of polar-orbiting satellite data over a wide region containing a network of direct readout stations and their rapid delivery to the global user community through regional processing centres. This initiative has improved weather forecasts over the globe, and is being expanded. RARS is comprised of several regional components, one of which, the Asia Pacific Regional ATOVS Retransmission Service (AP-RARS), covers the Asia-Pacific Region.
General information for this service can be found on the World Meteorological Organization's RARS web site.
Asia-Pacific RARS
The Asia-Pacific RARS (AP-RARS) is handled by the Dissemination Centres at Tokyo and Melbourne.
Participants within the AP-RARS are shown on the preceding map and detailed in the table below. The area of coverage is the area within approximately 2500km of a ground reception site, shown by red outlines on the map.
Table of AP-RARS Sites
| Operator (in alphabetical Order) | AP-RARS Station | Latitude | Longitude |
|---|---|---|---|
| Australian Institute of Marine Science | Townsville | 19.28°S | 147.05°E |
| Bureau of Meteorology | Casey | 66.26°S | 110.53°E |
| Davis | 68.58°S | 077.97°E | |
| Darwin | 12.46°S | 130.84°E | |
| Melbourne | 37.88°S | 144.96°E | |
| (Perth reception is performed by WASTAC) | Perth | 31.95°S | 115.89°E |
| China Meteorological Administration | Beijing | 39.93°N | 118.28°E |
| Guangzhou | 23.13°N | 113.30°E | |
| Urumuqi | 43.78°N | 087.60°E | |
| Hong Kong Observatory | Hong Kong | 22.30°N | 114.00°E |
| Japan Meteorological Agency | Kiyose | 35.77°N | 139.53°E |
| Syowa | 69.00°S | 039.58°E | |
| Korea Meteorological Administration | Jincheon | 36.99°N | 127.43°E |
| National Environment Agency | Singapore | 01.36°N | 103.92°E |
| National Institute of Water and Atmospheric Research (NZ) | Maupuia | 41.30°S | 174.80°E |
For a complete listing of RARS sites please refer to the WMO RARS Stations Implementation Status and Plans. For the station coding formats, please refer to the WMO RARS Coding summary Excel document.
Bureau Coverage
Australia reception stations on the Australian mainland and at Australia's Antarctic stations provide reception for a region extending from the south pole to north of the equator, and from New Zealand in the east to 2500km west of Perth in the Indian Ocean. The preceding image shows the coverage of the Bureau's polar orbiting satellite reception ground stations.
Processing Software
Information about the ATOVS and AVHRR Pre-processing Package (AAPP) is available at the UK Met Office
Target timeliness of the service
The Australian RARS service is capable of delivering more than 95% of data within 30 minutes from the start of the ingest from all mainland ingest sites. There is limited bandwidth available for data transfer from Antarctic stations, hence data is available approximately 60 minutes from the start of the ingest. Note that for Davis, the HRPT file has the AVHRR set to zero and the file is transmitted over the limited bandwidth more efficiently making it available within 30 minutes from the start of the ingest.
Target availability of the service
Given the antenna capacity of the Bureau sites, the target availability of the service is 90%. This figure is defined as the ratio of the actual number of individual product files to the number of product files the Bureau has the capacity to produce. This is based on the EARS standard .
Distribution mechanism
The primary distribution mechanism is via the Global Telecommunications System (GTS). Data is sent to the Regional Telecommunications Hub in Tokyo (RTH Tokyo), as well as to Exeter in the UK.
Obtaining AP-RARS
The contact/coordinator for the Asia-Pacific RARS is Dr Anthony Rea. For enquiries concerning operational matters related to the Asia-Pacific RARS, please contact the Satellite Operations group via satellites@bom.gov.au
|
Dr. Anthony Rea Bureau of Meteorology Observations & Infrastructure Division Box 1289 GPO Melbourne VIC 3001 AUSTRALIA Email: A.Rea@bom.gov.au Phone: +61 3 9669 4498 Fax: +61 3 9669 4168 |
Quality monitoring
RARS data quality monitoring takes place at two levels:
- The Regional Processing Centres are responsible for monitoring the performance of the RARS in their region;
- The Numerical Weather Prediction Satellite Application Facility (NWP SAF) routinely compares the data from all the RARS with global data.
In addition, data quality flags and indicators are generated during processing by the AAPP software and are embedded in the format of the retransmitted data alerting users to any inherent quality problems that might be present.
Monitoring by Regional Processing Centres
The standards for RARS operators are defined in an Operator Standards document. These standards include a definition of service related information that should be gathered and published. Each RARS Regional Processing Centre is responsible for monitoring the completeness of the data collected from the regional network of direct readout stations and retransmitted by the Centre. Data reception monitoring is based on a comparison of the actual data received by the Regional Processing Centre with that expected from the nominal regional configuration. Data retransmission monitoring involves maintaining a record of the completeness and timeliness of all data sets retransmitted. The results of all data monitoring are published on the Regional Processing Centres' web sites.
The UK Met office provides comparisons generated from RARS and global NOAA satellite data in addition to a daily summary. The comparisons are made with HIRS level 1d data (HIRS, AMSU-A and AMSU-B/MHS on the HIRS grid). The level 1d files are generated using AAPP from the incoming level 1c RARS data.