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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...
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Ano: 2017 URL: http://archimer.ifremer.fr/doc/00376/48758/49151.pdf
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A revised L-band radio-brightness sensitivity to extreme winds under tropical cyclones: The 5 year SMOS-Storm database ArchiMer
Reul, Nicolas; Chapron, Bertrand; Zabolotskikh, E.; Donlon, C.; Quilfen, Yves; Guimbard, Sebastien; Piolle, Jean-francois.
Five years of SMOS L-band brightness temperature data intercepting a large number of tropical cyclones (TCs) are analyzed. The storm-induced half-power radio-brightness contrast (ΔI) is defined as the difference between the brightness observed at a specific wind force and that for a smooth water surface with the same physical parameters. ΔI can be related to surface wind speed and has been estimated for ~ 300 TCs that intercept with SMOS measurements. ΔI, expressed in a common storm-centric coordinate system, shows that mean brightness contrast monotonically increases with increased storm intensity ranging from ~ 5 K for strong storms to ~ 24 K for the most intense Category 5 TCs. A remarkable feature of the 2D mean ΔI fields and their variability is that...
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Ano: 2016 URL: https://archimer.ifremer.fr/doc/00324/43542/43178.pdf
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A simplified model for the baroclinic and barotropic ocean response to moving tropical cyclones: 1. Satellite Observations ArchiMer
Kudryavtsev, Vladimir; Monzikova, Anna; Combot, Clement; Chapron, Bertrand; Reul, Nicolas; Quilfen, Yves.
Changes of sea surface temperature (SST) and height (SSH) derived from 20‐days passive microwave and altimeter measurements for three tropical cyclones (TCs), Jimena, Ignacio and Kilo, during the 2015 Pacific hurricane season, sampling different stages of intensification, wind speeds, radii, Coriolis parameter, translation velocities, and ocean stratification conditions, are reported and analyzed. As triggered along the path of moving TCs, very large interior ocean displacements can occur to leave prominent SSH anomalies in the TC wake. Resulting surface depressions can reach.3‐.5 m, depending upon size, translation speed, and ocean stratification conditions. These signatures can be quite persistent, i.e. more than few weeks, to possibly be intercepted...
Tipo: Text Palavras-chave: Tropical cyclones; Surface temperature anomalies; Surface height anomalies.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00491/60252/63653.pdf
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Altimeter dual-frequency observations of surface winds, waves, and rain rate in tropical cyclone Isabel - art. no. C01004, ArchiMer
Quilfen, Yves; Tournadre, Jean; Chapron, Bertrand.
[1] Extreme weather events such as tropical cyclones are difficult to observe with conventional means. Satellite-based observations provide essential measurements of key parameters governing tropical cyclones. They are critical for short-term forecasting. Radiometers onboard the Defense Meteorological Satellite Program satellite series, WindSat and Tropical Rainfall Measuring Mission satellites, scatterometers onboard the ERS, ADEOS, and QuikScat satellites offer unprecedented synoptic observations of surface wind and atmospheric liquid water content, revealing the storm structures with good accuracy. However, satellite estimates do not provide direct measurements of geophysical parameters and can suffer from limitations linked to the sensors...
Tipo: Text Palavras-chave: Mesearement limitations; Dual frequency altimeter; High resolution measurement; Tropical cyclone.
Ano: 2006 URL: http://archimer.ifremer.fr/doc/2006/publication-1033.pdf
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Assessment of wind-forcing impact on a global wind-wave model using the TOPEX altimeter ArchiMer
Feng, H; Vandemark, D; Quilfen, Yves; Chapron, Bertrand; Beckley, B.
The study presents assessment of an operational wave model (Wavewatch III), focusing upon the model sensitivity to wind-forcing products. Four wind fields are used to drive the model, including the NCEP/NCAR reanalysis and three other products that assimilate various satellite wind measurements having high spatial resolution, including the QuikSCAT scatterometer. Three wave field statistics: significant wave height, mean zero-crossing wave period, and mean square slope are compared with collocated TOPEX altimeter derivatives to gauge the relative skill of differing wind-forced model runs, as well as to demonstrate an extended use of the altimeter beyond simply supplying wave height for wave model validation and assimilation. Results suggest that model...
Tipo: Text Palavras-chave: Sea state bias; Wind forcing; Scatterometer; Altimeter; Wave modeling.
Ano: 2006 URL: http://archimer.ifremer.fr/doc/2006/publication-1861.pdf
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Global average of air-sea CO2 transfer velocity from QuikSCAT scatterometer wind speeds ArchiMer
Boutin, J.; Quilfen, Yves; Merlivat, L.; Piolle, Jean-francois.
The absolute calibration of the relationship between air-sea CO2 transfer velocity, k, and wind speed, U, has been a topic of debate for some time, because k global average, < k >, as deduced from Geochemical Ocean Sections Study oceanic C-14 inventory has differed from that deduced from experimental k-U relationships. Recently, new oceanic C-14 inventories and inversions have lead to a lower < k >. In addition, new measurements performed at sea in high-wind speed conditions have led to new k-U relationship. Meanwhile, quality and sampling of satellite wind speeds has greatly improved. The QuikSCAT scatterometer has provided high-quality wind speeds for more than 7 years. This allows us to estimate the global distributions of k computed using...
Tipo: Text Palavras-chave: CO2 transfer velocity; QuikSCAT; CARIOCA.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/2009/publication-6394.pdf
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Haline hurricane wake in the Amazon/Orinoco plume: AQUARIUS/SACD and SMOS observations ArchiMer
Grodsky, Semyon A.; Reul, Nicolas; Lagerloef, Gary; Reverdin, Gilles; Carton, James A.; Chapron, Bertrand; Quilfen, Yves; Kudryavtsev, Vladimir N.; Kao, Hsun-ying.
At its seasonal peak the Amazon/Orinoco plume covers a region of 10^6 km2 in the western tropical Atlantic with more than 1m of extra freshwater, creating a near-surface barrier layer (BL) that inhibits mixing and warms the sea surface temperature (SST) to >29oC. Here new sea surface salinity (SSS) observations from the Aquarius/SACD and SMOS satellites help elucidate the ocean response to hurricane Katia, which crossed the plume in early fall, 2011. Its passage left a 1.5psu high haline wake covering >10^5 km2 (in its impact on density, the equivalent of a 3.5oC cooling) due to mixing of the shallow BL. Destruction of this BL apparently decreased SST cooling in the plume, and thus preserved higher SST and evaporation than outside. Combined with SST,...
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Ano: 2012 URL: https://archimer.ifremer.fr/doc/00094/20540/18943.pdf
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Impact of rain cell on scatterometer data: 1. Theory and modeling - art. no. 3225 ArchiMer
Tournadre, Jean; Quilfen, Yves.
[1] The two scatterometers currently in operation, the Ku-band NASA Seawinds on the QuikScat satellite and the C-band AMI-Wind on the ERS-2 satellite, are designed to infer the ocean wind vectors from sea surface radar backscatter measurements. They provide excellent coverage of the ocean, and their wind products are of great value for ocean and meteorological communities. However, the presence of rain within scatterometer cells can significantly modify the sea surface backscatter coefficient and hence alter the wind vector retrieval. These perturbations can hamper the analysis of wind fields within atmospheric low-pressure systems or tropical cyclones. Rain perturbations result from volume scattering and attenuation by raindrops in the atmosphere as well...
Tipo: Text Palavras-chave: Model of interaction; Ocean surface winds; Rain; Scatterometer.
Ano: 2003 URL: http://archimer.ifremer.fr/doc/2003/publication-513.pdf
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Impact of rain cell on scatterometer data: 2. Correction of Seawinds measured backscatter and wind and rain flagging ArchiMer
Tournadre, Jean; Quilfen, Yves.
In October and early November 1999, the GOGP99 experiment collected hydrological, currentmeter, tide recorder, thermistor and drifting buoy data near the Strait of Hormuz. Data analysis provides the water mass structure in the Strait: Persian Gulf Water (PGW) core is banked against the Omani coast, while Indian Ocean Surface Water (IOSW) lies near the Iranian coast. These water masses are most often covered by a homogeneous surface layer. Thermohaline characteristics of the PGW core decrease substantially downstream, from the Persian/Arabian Gulf to the Gulf of Oman. PGW and IOSW thermohaline characteristics and distribution also exhibit notable changes at periods shorter than a month as shown by repeated hydrological sections. The tidal signal measured...
Tipo: Text Palavras-chave: Wind retrieval; Rain; Scatterometer.
Ano: 2005 URL: http://archimer.ifremer.fr/doc/2005/publication-388.pdf
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Importance of the sea surface curvature to interpret the normalized radar cross section - art. no. C10002 ArchiMer
Mouche, Alexis; Chapron, Bertrand; Reul, Nicolas; Hauser, D; Quilfen, Yves.
[1] Asymptotic models ( small perturbation and small slope approximation at first-order, Kirchhoff approximation or two-scale model) used to predict the normalized radar cross section of the sea surface generally fail to reproduce in detail backscatter radar measurements. In particular, the predicted polarization ratio versus incidence and azimuth angles is not in agreement with experimental data. This denotes the inability of these standard models to fully take into account the roughness properties with respect to the sensor's configuration of measurement ( frequency, incidence, and polarization). On the basis of particular assumptions, to decompose the scattered electromagnetic field between zones covered with freely propagating waves and others where...
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Ano: 2007 URL: http://archimer.ifremer.fr/doc/2007/publication-3577.pdf
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Multisensor observations of the Amazon-Orinoco river plume interactions with hurricanes ArchiMer
Reul, Nicolas; Quilfen, Yves; Chapron, Bertrand; Fournier, Severine; Kudryavtsev, Vladimir; Sabia, Roberto.
An analysis is presented for the spatial and intensity distributions of North Atlantic extreme atmospheric events crossing the buoyant Amazon-Orinoco freshwater plume. The sea surface cooling amplitude in the wake of an ensemble of storm tracks traveling in that region is estimated from satellite products for the period 1998-2012. For the most intense storms, cooling is systematically reduced by approximate to 50% over the plume area compared to surroundings open-ocean waters. Historical salinity and temperature observations from in situ profiles indicate that salt-driven vertical stratification, enhanced oceanic heat content, and barrier-layer presence within the plume waters are likely key oceanic factors to explain these results. Satellite SMOS surface...
Tipo: Text Palavras-chave: Hurricanes; Amazon-Orinocco river plume; SMOS SSS; Cooling inhibition; Barrier-layer; Haline stratification.
Ano: 2014 URL: https://archimer.ifremer.fr/doc/00252/36326/34855.pdf
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Observation of tropical cyclones by high-resolution scatterometry ArchiMer
Quilfen, Yves; Chapron, Bertrand; Elfouhaily, Tanos; Katsaros, Kristina; Tournadre, Jean.
Unprecedented views of surface wind fields in tropical cyclones thereafter TCs) are provided by the European Remote Sensing Satellite (ERS) C band scatterometer. Scatterometer measurements at C band are able to penetrate convective storms clouds, observing the surface wind fields with good accuracy. However the resolution of the measurements (50x50 km(2)) limits the interpretation of the scatterometer signals in such mesoscale events. The strong gradients of the surface wind existing at scales of a few kms are smoothed in the measured features such as the intensity and location of the wind maxima, and the position of the center. Beyond the ERS systems, the scatterometers on-board the ADEOS and METOP satellites, designed by the Jet Propulsion Laboratory and...
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Ano: 1998 URL: http://archimer.ifremer.fr/doc/00251/36257/34805.pdf
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Observing and Studying Extreme Low Pressure Events with Altimetry ArchiMer
Carrere, Loren; Mertz, Francoise; Dorandeu, Joel; Quilfen, Yves; Patoux, Jerome.
The ability of altimetry to detect extreme low pressure events and the relationship between sea level pressure and sea level anomalies during extra-tropical depressions have been investigated. Specific altimeter treatments have been developed for tropical cyclones and applied to obtain a relevant along-track sea surface height (SSH) signal: the case of tropical cyclone Isabel is presented here. The S- and C-band measurements are used because they are less impacted by rain than the Ku-band, and new sea state bias (SSB) and wet troposphere corrections are proposed. More accurate strong altimeter wind speeds are computed thanks to the Young algorithm. Ocean signals not related to atmospheric pressure can be removed with accuracy, even within a Near Real Time...
Tipo: Text Palavras-chave: Barotropic model; Sea level pressure; Extra tropical depressions; Tropical cyclones; Detection; Altimetry.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/2009/publication-6350.pdf
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Ocean surface wave-current signatures from satellite altimeter measurements ArchiMer
Quilfen, Yves; Chapron, Bertrand.
Ocean currents can strongly impact the propagation of swell systems. Satellite altimetry routinely provides measurements of ocean surface significant wave heights (Hs). A self‐consistent space‐scale decomposition is applied to Hs measurements obtained from different altimeters. This method helps reveal overlooked statistical properties at scales less than 100 km, where meso‐ and sub‐mesoscale upper ocean circulation drives a significant part of the variability in the coupled ocean‐atmosphere system. In particular, systematic signatures related to wave‐current interactions are clear at global and regional scales. In the Agulhas current system, the proposed space‐scale decomposition further reveals organized and persistent patterns. To leading order, the...
Tipo: Text Palavras-chave: Altimeter observations; Wave-current interactions; Denoising method.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00472/58359/60917.pdf
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Phenomenal sea states and swell from a North Atlantic Storm in February 2011: a comprehensive analysis ArchiMer
Hanafin, Jennifer; Quilfen, Yves; Ardhuin, Fabrice; Sienkiewicz, Joseph; Queffeulou, Pierre; Obrebski, Mathias; Chapron, Bertrand; Reul, Nicolas; Collard, Fabrice; Corman, David; De Azevedo, Eduardo B.; Vandemark, Doug; Stutzmann, Eleonore.
Tipo: Text
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00094/20538/18197.pdf
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Prediction of sea level anomalies using ocean circulation model forced by scatterometer wind and validation using TOPEX/Poseidon data ArchiMer
Quilfen, Yves; Bentamy, Abderrahim; Delecluse, P; Katsaros, K; Grima, N.
Uncertainties in the surface wind field have long been recognized as a major limitation in the interpretation of results obtained by oceanic circulation models. It is especially true in the tropical oceans, where the response to wind forcing is very strong on short time scales. The purpose of this paper is to show that these uncertainties can be greatly reduced by using spaceborne wind sensors that provide accurate measurements on a global basis.Surface winds over the global oceans have been measured by scatterometry since the launch of the European Remote Sensing Satellite (ERS-1) in August 1991 by the European Space Agency, Noordwijk, The Netherlands, and is currently provided by ERS-2, launched in April 1995. The ground track wind vectors are processed...
Tipo: Text Palavras-chave: Ocean model; Ocean surface; Scatterometer; Sea level.
Ano: 2000 URL: http://archimer.ifremer.fr/doc/00000/10501/9560.pdf
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Salinity from space unlocks satellite-based assessment of ocean acidification ArchiMer
Land, Peter; Shutler, Jamie; Findlay, Helen; Girard Ardhuin, Fanny; Sabia, Roberto; Reul, Nicolas; Piolle, Jean-francois; Chapron, Bertrand; Quilfen, Yves; Salisbury, Joseph; Vandemark, Douglas; Bellerby, Richard; Bhadury, Punyasloke.
Approximately a quarter of the carbon dioxide (CO2) that we emit into the atmosphere is absorbed by the ocean. This oceanic uptake of CO2 leads to a change in marine carbonate chemistry resulting in a decrease of seawater pH and carbonate ion concentration, a process commonly called ‘Ocean Acidification’. Salinity data are key for assessing the marine carbonate system, and new space-based salinity measurements will enable the development of novel space-based ocean acidification assessment. Recent studies have highlighted the need to develop new in situ technology for monitoring ocean acidification, but the potential capabilities of space-based measurements remain largely untapped. Routine measurements from space can provide quasi-synoptic, reproducible...
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Ano: 2015 URL: https://archimer.ifremer.fr/doc/00247/35863/34384.pdf
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Satellites will address critical science priorities for quantifying ocean carbon ArchiMer
Shutler, Jamie D; Wanninkhof, Rik; Nightingale, Philip D; Woolf, David K; Bakker, Dorothee Ce; Watson, Andy; Ashton, Ian; Holding, Thomas; Chapron, Bertrand; Quilfen, Yves; Fairall, Chris; Schuster, Ute; Nakajima, Masakatsu; Donlon, Craig J.
The ability to routinely quantify global carbon dioxide (CO2) absorption by the oceans has become crucial: it provides a powerful constraint for establishing global and regional carbon (C) budgets, and enables identification of the ecological impacts and risks of this uptake on the marine environment. Advances in understanding, technology, and international coordination have made it possible to measure CO2 absorption by the oceans to a greater degree of accuracy than is possible in terrestrial landscapes. These advances, combined with new satellite‐based Earth observation capabilities, increasing public availability of data, and cloud computing, provide important opportunities for addressing critical knowledge gaps. Furthermore, Earth observation in...
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Ano: 2020 URL: https://archimer.ifremer.fr/doc/00590/70256/68305.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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Sea-leval (A) pressure index and the warm events in the tropical Atlantic ocean IRD
Tourre, Yves; Merle, Jacques; Quilfen, Yves.
Tipo: Text Palavras-chave: ZONE TROPICALE; EL NINO; TEMPERATURE DE SURFACE; CIRCULATION ATMOSPHERIQUE.
Ano: 1986 URL: http://www.documentation.ird.fr/hor/fdi:23959
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