![]() | The SMOS Mission: New Tool for Monitoring Key Elements of the Global Water Cycle Auteur(s) : Kerr, Yann H. Waldteufel, Philippe Wigneron, Jean-pierre Delwart, Steven Cabot, Francois Boutin, Jacqueline Escorihuela, Maria-jose Font, Jordi Éditeur(s) : IEEE Résumé : It is now well understood that data on soil moisture and sea surface salinity (SSS) are required to improve meteorological and climate predictions. These two quantities are not yet available globally or with adequate temporal or spatial sampling. It is recognized that a spaceborne L-band radiometer with a suitable antenna is the most promising way of fulfilling this gap. With these scientific objectives and technical solution at the heart of a proposed mission concept the European Space Agency (ESA) selected the Soil Moisture and Ocean Salinity (SMOS) mission as its second Earth Explorer Opportunity Mission. The development of the SMOS mission was led by ESA in collaboration with the Centre National d'Etudes Spatiales (CNES) in France and the Centro para el Desarrollo Tecnologico Industrial (CDTI) in Spain. SMOS carries a single payload, an L-Band 2-D interferometric radiometer operating in the 1400-1427-MHz protected band [1]. The instrument receives the radiation emitted from Earth's surface, which can then be related to the moisture content in the first few centimeters of soil over land, and to salinity in the surface waters of the oceans. SMOS will achieve an unprecedented maximum spatial resolution of 50 km at L-band over land (43 km on average over the field of view), providing multiangular dual polarized (or fully polarized) brightness temperatures over the globe. SMOS has a revisit time of less than 3 days so as to retrieve soil moisture and ocean salinity data, meeting the mission's science objectives. The caveat in relation to its sampling requirements is that SMOS will have a somewhat reduced sensitivity when compared to conventional radiometers. The SMOS satellite was launched successfully on November 2, 2009. Proceedings of the IEEE (0018-9219) (IEEE), 2010-05 , Vol. 98 , N. 5 , P. 666-687 Droits : 2010 IEEE – All Rights Reserved http://archimer.ifremer.fr/doc/00004/11483/8065.pdf DOI:10.1109/JPROC.2010.2043032 http://archimer.ifremer.fr/doc/00004/11483/ | Partager |
![]() | Sea Surface Salinity Observations from Space with the SMOS Satellite: A New Means to Monitor the Marine Branch of the Water Cycle Auteur(s) : Reul, Nicolas Fournier, Severine Boutin, Jacqueline Hernandez, Olga Maes, Christophe Chapron, Bertrand Alory, Gael Quilfen, Yves Éditeur(s) : Springer Résumé : While it is well known that the ocean is one of the most important component of the climate system, with a heat capacity 1,100 times greater than the atmosphere, the ocean is also the primary reservoir for freshwater transport to the atmosphere and largest component of the global water cycle. Two new satellite sensors, the ESA Soil Moisture and Ocean Salinity (SMOS) and the NASA Aquarius SAC-D missions, are now providing the first space-borne measurements of the sea surface salinity (SSS). In this paper, we present examples demonstrating how SMOS-derived SSS data are being used to better characterize key land–ocean and atmosphere–ocean interaction processes that occur within the marine hydrological cycle. In particular, SMOS with its ocean mapping capability provides observations across the world’s largest tropical ocean fresh pool regions, and we discuss from intraseasonal to interannual precipitation impacts as well as large-scale river runoff from the Amazon–Orinoco and Congo rivers and its offshore advection. Synergistic multi-satellite analyses of these new surface salinity data sets combined with sea surface temperature, dynamical height and currents from altimetry, surface wind, ocean color, rainfall estimates, and in situ observations are shown to yield new freshwater budget insight. Finally, SSS observations from the SMOS and Aquarius/SAC-D sensors are combined to examine the response of the upper ocean to tropical cyclone passage including the potential role that a freshwater-induced upper ocean barrier layer may play in modulating surface cooling and enthalpy flux in tropical cyclone track regions. Surveys In Geophysics (0169-3298) (Springer), 2014-05 , Vol. 35 , N. 3 , P. 681-722 Droits : Springer Science+Business Media Dordrecht 2013 http://archimer.ifremer.fr/doc/00152/26334/24430.pdf DOI:10.1007/s10712-013-9244-0 http://archimer.ifremer.fr/doc/00152/26334/ | Partager Voir aussi Sea surface salinity SMOS satellite Passive microwave remote sensing Oceanic freshwater cycle Télécharger |