DocumentCode :
1242695
Title :
Simulated SMOS Levels 2 and 3 Products: The Effect of Introducing ARGO Data in the Processing Chain and Its Impact on the Error Induced by the Vicinity of the Coast
Author :
Talone, Marco ; Camps, Adriano ; Mourre, Baptiste ; Sabia, Roberto ; Vall-llossera, Mercè ; Gourrion, Jérôme ; Gabarró, Carolina ; Font, Jordi
Author_Institution :
Dept. de Teor. del Senyal i Comunicacions, Univ. Politec. de Catalunya, Barcelona, Spain
Volume :
47
Issue :
9
fYear :
2009
Firstpage :
3041
Lastpage :
3050
Abstract :
The Soil Moisture and Ocean Salinity (SMOS) Mission is the second of the European Space Agency´s Living Planet Program Earth Explorer Opportunity Missions, and it is scheduled for launch in July 2009. Its objective is to provide global and frequent soil-moisture and sea-surface-salinity (SSS) maps. SMOS´ single payload is the Microwave Imaging Radiometer by Aperture Synthesis (MIRAS) sensor, an L-band 2-D aperture-synthesis interferometric radiometer. For the SSS, the output products of SMOS, at Level 3, will have global coverage and an accuracy of 0.1-0.4 psu (practical salinity units) over 100 times 100-200 times 200 km2 in 10-30 days. During the last few years, several studies have pointed out the necessity of combining auxiliary data with the MIRAS-measured brightness temperature to provide the required accuracy. In this paper, we propose and test two techniques to include auxiliary data in the SMOS SSS retrieval algorithm. Aiming at this, pseudo-SMOS Level-3 products have been generated according to the following steps: 1) A North Atlantic configuration of the NEMO-OPA ocean model has been run to provide consistent geophysical parameters; 2) the SMOS end-to-end processor simulator has been used to compute the brightness temperatures as measured by the MIRAS; 3) the SMOS Level-2 processor simulator has been applied to retrieve SSS values for each point and overpass; and 4) Level-2 data have been temporally and spatially averaged to synthesize Level-3 products. In order to assess the impact of the proximity to the coast at Level 3, and the effect of these techniques on it, two different zones have been simulated: the first one in open ocean and the second one in a coastal region, near the Canary Islands (Spain) where SMOS and Aquarius CAL/VAL activities are foreseen. Performance exhibits a clear improvement at Level 2 using the techniques proposed; at Level 3, a smaller effect has been recorded. Coastal proximity has been found to affect the retrieva- - l of up to 150 and 300 km from the coast, at Levels 2 and 3, respectively. Results for both scenarios are presented and discussed.
Keywords :
geophysical signal processing; microwave imaging; ocean chemistry; oceanographic techniques; radiometry; remote sensing; AD 2009 07; ARGO data effects; Aquarius CAL-VAL; Canary Islands; European Space Agency; L-band 2D aperture synthesis interferometric radiometer; Living Planet Program Earth Explorer Opportunity Missions; MIRAS measured brightness temperature; MIRAS sensor; Microwave Imaging Radiometer by Aperture Synthesis; NEMO-OPA ocean model; SMOS SSS retrieval algorithm; SMOS end to end processor simulator; Soil Moisture and Ocean Salinity Mission; auxiliary data; data processing chain; north Atlantic Ocean; sea surface salinity map; simulated SMOS level 2 product; simulated SMOS level 3 product; soil moisture map; ARGO; Level 3; Soil Moisture and Ocean Salinity (SMOS); coastal effects; sea-surface salinity (SSS);
fLanguage :
English
Journal_Title :
Geoscience and Remote Sensing, IEEE Transactions on
Publisher :
ieee
ISSN :
0196-2892
Type :
jour
DOI :
10.1109/TGRS.2008.2011618
Filename :
4815461
Link To Document :
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