|Copyright||2012 by the American Geophysical Union|
|Author(s)||Reul Nicolas1, Tenerelli Joseph3, Chapron Bertrand1, Vandemark Doug4, Quilfen Yves1, Kerr Yann2|
|Affiliation(s)||1 : IFREMER, Lab Oceanog Spatiale, F-29280 Plouzane, France.
2 : Ctr Etude Spatial Biosphere, F-31401 Toulouse 09, France.
3 : Collect Localisat Satellite, Div Radar, F-29280 Plouzane, France.
4 : Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA.
|Source||Journal Of Geophysical Research-oceans (0148-0227) (Amer Geophysical Union), 2012-02 , Vol. 117 , P. -|
|WOS© Times Cited||32|
|Abstract||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 period. Without correcting for rain effects, L-band wind-induced ocean surface brightness temperatures (TB) were co-located and compared to H*Wind analysis. We find the L-band ocean emissivity dependence with wind speed appears less sensitive to roughness and foam changes than at the higher C-band microwave frequencies. The first Stokes parameter on a ∼50 km spatial scale nevertheless increases quasi-linearly with increasing surface wind speed at a rate of 0.3 K/m s−1 and 0.7 K/m s−1 below and above the hurricane-force wind speed threshold (∼32 m s−1), respectively. Surface wind speeds estimated from SMOS brightness temperature images agree well with the observed and modeled surface wind speed features. In particular, the evolution of the maximum surface wind speed and the radii of 34, 50 and 64 knots surface wind speeds are consistent with GFDL hurricane model solutions and H*Wind analyses. The SMOS sensor is thus closer to a true all-weather satellite ocean wind sensor with the capability to provide quantitative and complementary surface wind information of interest for operational Hurricane intensity forecasts.|
Reul Nicolas, Tenerelli Joseph, Chapron Bertrand, Vandemark Doug, Quilfen Yves, Kerr Yann (2012). SMOS satellite L-band radiometer: A new capability for ocean surface remote sensing in hurricanes. Journal Of Geophysical Research-oceans, 117, -. Publisher's official version : http://doi.org/10.1029/2011JC007474 , Open Access version : http://archimer.ifremer.fr/doc/00067/17805/