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A new generation of Tropical Cyclone Size measurements from space ArchiMer
Reul, Nicolas; Chapron, Bertrand; Zabolotskikh, E.; Donlon, C.; Mouche, Alexis; Tenerelli, Joseph; Collard, F.; Piolle, Jean-francois; Fore, A.; Yueh, S.; Cotton, J.; Francis, P.; Quilfen, Yves; Kudryavtsev, V..
Combined microwave brightness temperature measurements from recent L- and dual C-band satellite radiometers provide new estimates of surface wind speed structure in Tropical Cyclones which enhances temporal sampling capability for gale (34-knots), damaging (50-knots) and destructive (64-knots) wind radii. Wind radii estimates in Tropical Cyclones (TC) are crucial to help determine the TC wind structure for the production of effective warnings and to constrain initial conditions for a number of applications. In that context, we report on the capabilities of a new generation of satellite microwave radiometers operating at L-band frequency (~1.4 GHz) and dual C-band (~6.9 and 7.3 GHz). These radiometers provide wide swath (> 1000 km) coverage at a spatial...
Tipo: Text
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00376/48758/49151.pdf
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Earth-viewing L-band radiometer sensing of sea surface scattered celestial sky radiation - Part I: General characteristics ArchiMer
Tenerelli, Joseph; Reul, Nicolas; Mouche, Alexis; Chapron, Bertrand.
The "galactic glitter" phenomenon at L-band, i.e., the scattering of celestial sky radiation by the rough ocean surface, is examined here as a potential source of error for sea surface salinity (SSS) remote sensing. We begin by considering the transformations that must be applied to downwelling celestial noise in order to compute the eventual impact on the antenna temperature. Then, outside the context of any particular measurement system, we use approximate scattering models along with a model for the equilibrium wind wave spectrum to examine how the scattered signal at the surface might depend on the geophysical conditions and scattering geometry. It is found that, when the specular point lies far away from the galactic plane, where the incident...
Tipo: Text Palavras-chave: Scattering; Remote sensing; Radiometry.
Ano: 2008 URL: http://archimer.ifremer.fr/doc/2008/publication-3922.pdf
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Earth-Viewing L-Band Radiometer Sensing of Sea Surface Scattered Celestial Sky Radiation—Part II: Application to SMOS ArchiMer
Reul, Nicolas; Tenerelli, Joseph; Floury, N; Chapron, Bertrand.
We examine how the rough sea surface scattering of L-band celestial sky radiation might affect the measurements of the future European Space Agency Soil Moisture and Ocean Salinity (SMOS) mission. For this purpose, we combined data from several surveys to build a comprehensive all-sky L-band celestial sky brightness temperature map for the SMOS mission that includes the continuum radiation and the hydrogen line emission rescaled for the SMOS bandwidth. We also constructed a separate map of strong and very localized sources that may exhibit L-band brightness temperatures exceeding 1000 K. Scattering by the roughened ocean surface of radiation from even the strongest localized sources is found to reduce the contributions from these localized strong sources...
Tipo: Text Palavras-chave: Sea surface electromagnetic scattering; Microwave radiometry.
Ano: 2008 URL: http://archimer.ifremer.fr/doc/2008/publication-3636.pdf
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Modeling sun glitter at L-band for sea surface salinity remote sensing with SMOS ArchiMer
Reul, Nicolas; Tenerelli, Joseph; Chapron, Bertrand; Waldteufel, P.
Since the sun is an extremely strong radiation source at L-band, accounting for sun glint over the ocean, i.e., solar radiation reflected by the sea surface toward downward-looking radiometers, raises a significant challenge for the remote sensing of sea surface salinity. This paper describes a dedicated physical model for sun glint at L-band frequencies and provides quantitative and qualitative estimates of the sun glint contamination impinging the antenna of the Microwave Imaging Radiometer with Aperture Synthesis interferometer onboard the future European Space Agency's Soil Moisture and Ocean Salinity (SMOS) mission, The sun brightness temperature expected during the mission period is first estimated from past solar flux data with an expected range of...
Tipo: Text Palavras-chave: Sun glitter; Sea surface salinity SSS; Rough surface scattering; Ocean remote sensing; Microwave radiometry.
Ano: 2007 URL: http://archimer.ifremer.fr/doc/2007/publication-3565.pdf
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Overview of the First SMOS Sea Surface Salinity Products. Part I: Quality Assessment for the Second Half of 2010 ArchiMer
Reul, Nicolas; Tenerelli, Joseph; Boutin, Jaqueline; Chapron, Bertrand; Paul, Frederic; Brion, Emilie; Gaillard, Fabienne; Archer, Olivier.
Multi-angular images of the brightness temperature (TB) of the Earth at 1.4 GHz are reconstructed from the Soil Moisture and Ocean Salinity (SMOS) satellite sensor data since end 2009. Sea surface salinity (SSS) products remote sensing from space is being attempted using these data over the world oceans. The quality of the first version of the European Space Agency operational Level 2 (L2) SSS swath products is assessed in this paper, using satellite/in situ SSS data match-ups that were collected over the second half of 2010. This database reveals that 95% of the SMOS L2 products show a global error standard deviation on the order of ∼1.3 practical salinity scale. Simple spatiotemporal aggregation of the L2 products to generate monthly SSS maps at 1◦ × 1◦...
Tipo: Text Palavras-chave: L-band; Microwave radiometry; Ocean salinity; Sea surface.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00072/18313/16109.pdf
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Overview of the SMOS sea surface salinity prototype processor ArchiMer
Zine, S; Boutin, J; Font, J; Reul, Nicolas; Waldteufel, P; Gabarro, C; Tenerelli, Joseph; Petitcolin, F; Vergely, J; Talone, M; Delwart, S.
The L-band interferometric radiometer onboard the Soil Moisture and Ocean Salinity mission will measure polarized brightness temperatures (Tb). The measurements are affected by strong radiometric noise. However, during a satellite overpass, numerous measurements are acquired at various incidence angles at the same location on the Earth's surface. The sea surface salinity (SSS) retrieval algorithm implemented in the Level 2 Salinity Prototype Processor (L2SPP) is based on an iterative inversion method that minimizes the differences between Tb measured at different incidence angles and Tb simulated by a full forward model. The iterative method is initialized with a first-guess surface salinity that is iteratively modified until an optimal fit between the...
Tipo: Text Palavras-chave: Salinity; Oceanography; Microwave radiometry.
Ano: 2008 URL: http://archimer.ifremer.fr/doc/2008/publication-3914.pdf
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Remote Sensing of Sea Surface Salinity From CAROLS L-Band Radiometer in the Gulf of Biscay ArchiMer
Martin, Adrien; Boutin, Jacqueline; Hauser, Daniele; Reverdin, Gilles; Parde, Mickael; Zribi, Mehrez; Fanise, Pascal; Chanut, Jerome; Lazure, Pascal; Tenerelli, Joseph; Reul, Nicolas.
A renewal of interest for the radiometric L-band Sea Surface Salinity (SSS) remote sensing appeared in the 1990s and led to the Soil Moisture and Ocean Salinity (SMOS) satellite launched in November 2009 and to the Aquarius mission (launched in June 2011). However, due to low signal to noise ratio, retrieving SSS from L-band radiometry is very challenging. In order to validate and improve L-band radiative transfer model and salinity retrieval method used in SMOS data processing, the Cooperative Airborne Radiometer for Ocean and Land Studies (CAROLS) was developed. We analyze here a coastal flight (20 May 2009), in the Gulf of Biscay, characterized by strong SSS gradients (28 to 35 pss-78). Extensive in-situ measurements were gathered along the plane track....
Tipo: Text Palavras-chave: L-band; Microwave radiometry; Remote sensing; Retrieval method; Sea surface salinity (SSS); Soil Moisture and Ocean Salinity (SMOS); Wind speed.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00079/18997/16600.pdf
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Sea Surface Salinity Observations from Space with the SMOS Satellite: A New Means to Monitor the Marine Branch of the Water Cycle ArchiMer
Reul, Nicolas; Fournier, Severine; Boutin, Jacqueline; Hernandez, Olga; Maes, Christophe; Chapron, Bertrand; Alory, Gael; Quilfen, Yves; Tenerelli, Joseph; Morisset, Simmon; Kerr, Yann; Mecklenburg, Susanne; Delwart, Steven.
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...
Tipo: Text Palavras-chave: Sea surface salinity; SMOS satellite; Passive microwave remote sensing; Oceanic freshwater cycle.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00152/26334/24430.pdf
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SMOS satellite L-band radiometer: A new capability for ocean surface remote sensing in hurricanes ArchiMer
Reul, Nicolas; Tenerelli, Joseph; Chapron, Bertrand; Vandemark, Doug; Quilfen, Yves; Kerr, Yann.
The Soil Moisture and Ocean Salinity (SMOS) mission currently provides multiangular L-band (1.4 GHz) brightness temperature images of the Earth. Because upwelling radiation at 1.4 GHz is significantly less affected by rain and atmospheric effects than at higher microwave frequencies, these new SMOS measurements offer unique opportunities to complement existing ocean satellite high wind observations that are often contaminated by heavy rain and clouds. To illustrate this new capability, we present SMOS data over hurricane Igor, a tropical storm that developed to a Saffir-Simpson category 4 hurricane from 11 to 19 September 2010. Thanks to its large spatial swath and frequent revisit time, SMOS observations intercepted the hurricane 9 times during this...
Tipo: Text
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00067/17805/15330.pdf
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