Royal Netherlands Meteorological Institute

Updated @ 2012-05-28 17:06 utc
EARS ASCAT 12.5-km product viewer
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Wind Products
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Product status: operational
Ascending passes
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Descending passes
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Modifications/anomalies
23-Oct-2011 Due to a Metop-A spontaneous payload switch-off, the ASCAT wind products have been unavailable between 22 October, 21:54 and 23 October, 15:45 UTC sensing time.
18-Oct-2011 The provision of ASCAT winds has been delayed between 18 October 0:00 and 5:00 UTC due to a hardware problem at KNMI.
30-Sep-2011 Due to an issue in the level 1 backscatter data, no winds were available in the descending Metop passes between 29 September, 2:21 and 29 September 14:36 UTC.
29-Sep-2011 Some winds have been missing between 28 September, 11:00 and 29 September, 3:00 UTC due to a Metop out of plane manoeuvre.
30-Aug-2011 The provision of ASCAT wind data has been delayed on 29 August, between 9:00 and 14:00 UTC due to a hardware problem at KNMI.
23-Aug-2011 AHRPT data from a number of ground stations are now available in addition to the data acquired at Svalbard.
16-Aug-2011 AWDP version 2_1_00: up to four wind solutions present in the 12.5 km BUFR products, use of NWP Ocean Calibration for more uniform wind characteristics across the swath.
16-May-2011 ASCAT winds have been unavailable between 14 May, 10:51 and 16 May, 10:50 UTC due to an instrument anomaly.
05-Jan-2011 ASCAT winds had reduced quality (wind speed bias approx. 0.5 m/s) and have been temporarily unavailable due to a problem in the ASCAT on-board power gain between 3 January, 3:30 and 4 January, 15:15 UTC.
06-Oct-2010 No winds have been available between 5 October, 12:00 and 6 October, 6:00 UTC due to a MetOp out of plane manoeuvre.
20-Mar-2010 ASCAT data were unavailable for instrument sensing times from 19 March, 23:30 to 20 March, 06:24 UTC.
09-Mar-2010 EARS Level 1 data have been delayed between 9 March, 15:00 and 20:00 UTC.
08-Mar-2010 EARS data from Svalbard station have been delayed between 8 March, 6:00 and 11:00 UTC.
04-Mar-2010 No winds have been available between 4 March, 6:53 and 10:05 UTC due to a system failure in the Level 1 processor.
18-Feb-2010 No winds have been available between 18 February, 9:50 and 15:24 UTC due to a spontaneous ASCAT switch-off.
12-Jan-2010 AWDP version 1_0_19: products in BUFR Edition 4 and up to four wind solutions used for ambiguity removal (only one solution present in BUFR products).
17-Sep-2009 No winds have been available between 17 September, 13:48 and 16:00 UTC due to a MetOp out of plane manoeuvre.
16-Sep-2009 Data have been unavailable between 16 Sep, 0:00 and 13:00 UTC due to a problem at the Svalbard ground station.
08-Sep-2009 EARS ASCAT data are available on the GTS.
01-Sep-2009 AWDP version 1_0_18: no changes for EARS products.
30-Jul-2009 There have been problems with the overview images on the website which are solved now.
08-Jul-2009 Due to a local network switch problem at KNMI, wind products have been interrupted and delayed between 3:00 and 6:00 UTC.
13-May-2009 No winds have been available between 12 May, 17:00 and 13 May, 1:00 UTC due to power maintenance at the Svalbard ground station.
21-Apr-2009 AWDP version 1_0_17: upgrades in BUFR encoding.
06-Jan-2009 Data have been unavailable on 31 Dec. and 1 Jan. due to network problems.
11-Dec-2008 EARS ASCAT winds are available now to all users.
Description
The ASCAT Wind Product contains measurements of the wind direction and wind speed above the sea surface. The measurements are obtained through the processing of scatterometer data originating from the ASCAT instrument on EUMETSAT's MetOp satellite, as described in the ASCAT Wind Product User Manual.

The processing is done in near-real time. In the context of this regional service, the last 30 minutes of the ASCAT MetOp dump over the main acquisition ground station in Svalbard are processed jointly by the EARS ground system and KNMI. From the sensing time of the last measurement in a product, it takes approximately 15 minutes to get the corresponding wind product ready at KNMI. Since each product contains approximately 30 minutes of data, the timeliness of the oldest data in the products is about 45 minutes. For latitudes equivalent to Europe, the timeliness of the data is approximately 30 minutes, in line with the goals of the EARS service for products generated from satellite direct broadcast data.

This product in intended for nowcasting applications, where high timeliness and resolution are very important. In order to further tailor the product to nowcasting applications, only the selected scatterometer wind vector after ambiguity removal is provided.

The last 22 hours of data are shown in two separate plots showing ascending and descending tracks, respectively. This is done to avoid overlap of data in the pictures. Note that also data from previous days can be displayed using the link on the right hand side. The overview plots show color coded wind speed measurements. If you click somewhere in the satellite track, a picture appears showing the scatterometer winds in more detail.

Product monitoring information in near-real time is available through the corresponding link on the right hand side.
Access to products
This wind product is available in BUFR format. The data are disseminated through the EUMETCast system; for access please contact EUMETSAT. The products are also available on a password protected FTP server (products of the last three days only). Contact the KNMI scatterometer team for access. The BUFR products are available on the Global Telecommunication System (GTS), as well. The messages are distributed to the Exeter node and can be identified by: header (T1T2A1A2ii) = ISXN[11-16]; CCCC = EHDB.

Note: All intellectual property rights of the OSI SAF and EARS products belong to EUMETSAT. The use of these products is granted to every interested user, free of charge. If you wish to use these products, EUMETSAT's copyright credit must be shown by displaying the words "copyright (year) EUMETSAT" on each of the products used.
Acknowledgements
The regional products are developed under the EUMETSAT Advanced Retransmission Service (EARS), a project by EUMETSAT and KNMI.

The processing software for the KNMI wind product is developed within the framework of the Numerical Weather Prediction Satellite Application Facility (NWP SAF) sponsored by EUMETSAT.