DINEOF daily cloud-free SST for the Canary-Madeira region
DINEOF (Data INterpolating Empirical Orthogonal Functions) is an EOF-based technique to reconstruct missing data in satellite images. Initial cloudy data, reconstruction, outliers and error field (all calculated by DINEOF) for the last 10 days are shown. This product is updated daily with the latest SST data. The different steps used to produce the filled images are described here
SST gridded fields are downloaded from the Medspiration project (http://www.medspiration.org) available on the Ifremer FTP server. The sensor AATSR (Advanced Along-Track Scanning Radiometer, http://envisat.esa.int/instruments/aatsr/) on the ENVISAT satellite provide measurements with 1~km resolution at nadir. In order to avoid problem of warm pixels, only nigh time images are processed.
The region studied here is rich in small scales processes: the coastal upwelling along the African coast, the eddies in the wakes of the islands (Madeira and Canary Archipelagos), and the upwelling filaments near Cape Ghir (30° 38'N, 9° 53'W) and Cape Jubi (27° 56N, 12° 55'30''W).
Rui Caldeira, http://wakes.uma.pt/index.php: cruises for the study of the Selvage Islands (Portugal), 8-28 June 2010.
PRODUCT DESCRIPTIONEach image is composed of 517 X 560 pixels, representing the SST.
- The first figure displays the original data, extracted from the Medspiration database. The white pixels indicate the presence of clouds, or pixels that were not measured by the sensor during the tracks of the satellite.
- The second image is the complete DINEOF reconstruction. It means that all the pixels, even those initially assigned with a SST value, undergo a reconstruction.
- The third one is a combination of the first two: when the pixel has already a value, it is kept.
- The last one is an error map, estimated using the method described by Beckers et al. (2006).
PRODUCT DOWNLOADThe reconstructed fields in netcdf format (one file per day) will be made available here. Results are directly viewable through the Ocean Browser:
- click on Canary, then on DINEOF + original data SST reconstruction
- select SST and click on 'plot-update' to get the SST on the map
- adapt the colorbar options and the style of plot (contour, filled contour, pcolor)
- click on the button 'download' and select the output format.