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Altimetry.dk is a website that delivers near real-time (NRT) data from operating altimetric missions. The measurements are retrieved from the Radar Altimeter Database System (RADS), and at the moment are based on CryoSat-2, SARAL, and Jason-2. In a near future Jason-3 and Sentinel-3A will be integrated, according to RADS availability. The website is divided in two parts: the homepage and the ARCHIVE.
The homepage shows the last data acquired from RADS, which are delivered as regional Sea Level Anomalies (SLA), Significant Wave Height (SWH) and wind speed. These three components are supplied every 12 or 24 hours. The former shows the observations obtained from RADS every 12 hours, while the latter shows the observations of the last 3 days. By clicking on the blue icons on the right-hand side of the page (e.g. the icon "Global Data") it is possible to download the plots and the NRT observations as ASCII files.
The files are named with the following format:
SS_RRRRRR_BBBBBBBBBBBBBB_EEEEEEEEEEEEEE.txt
where SS indicates the satellite, RRRRRR specifies the region, BBBBBBBBBBBBBB the time at which the data acquisition has started, and EEEEEEEEEEEEEE the time at which the data acquisition has ended. The acquisition time information has the format YYYYMMDDhhmmss.
Every file contains 8 columns:
TIME | CYCLE | PASS | LATITUDE | LONGITUDE | SLA | SWH | WIND SPEED
Time is in seconds, counting from 1985, SLA and SWH are in metres, and wind speed is in metres/second.
The second part of the website is the ARCHIVE. The ARCHIVE contains all the observations and plots obtained during each day. In this case the ASCII files have a different name format:
SS_RRRRRR_TTTTTTTT.txt
SS specifies the satellite, RRRRRR the region and TTTTTTTT the day of data acquisition. The column format is the same as the homepage data.
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