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Registros recuperados: 69 | |
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Dash, Prasanjit; Ignatov, Alexander; Martin, Matthew; Donlon, Craig; Brasnett, Bruce; Reynolds, Richard W.; Banzon, Viva; Beggs, Helen; Cayula, Jean-francois; Chao, Yi; Grumbine, Robert; Maturi, Eileen; Harris, Andy; Mittaz, Jonathan; Sapper, John; Chin, Toshio M.; Vazquez-cuervo, Jorge; Armstrong, Edward M.; Gentemann, Chelle; Cummings, James; Piolle, Jean-francois; Autret, Emmanuelle; Roberts-jones, Jonah; Ishizaki, Shiro; Hoyer, Jacob L.; Poulter, Dave. |
There are a growing number of level 4 (L4; gap-free gridded) sea surface temperature (SST) products generated by blending SST data from various sources which are available for use in a wide variety of operational and scientific applications. In most cases, each product has been developed for a specific user community with specific requirements guiding the design of the product. Consequently differences between products are implicit. In addition, anomalous atmospheric conditions, satellite operations and production anomalies may occur which can introduce additional differences. This paper describes a new web-based system called the L4 SST Quality Monitor (L4-SQUAM) developed to monitor the quality of L4 SST products. L4-SQUAM intercompares thirteen L4... |
Tipo: Text |
Palavras-chave: Sea surface temperature; Intercomparison; Climate data; Sea ice; Data centers. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00101/21188/19798.pdf |
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Wang, Yiming V.; Leduc, Guillaume; Regenberg, Marcus; Andersen, Nils; Larsen, Thomas; Blanz, Thomas; Schneider, Ralph R.. |
Different proxies for sea surface temperature (SST) often exhibit divergent trends for deglacial warming in tropical regions, hampering our understanding of the phase relationship between tropical SSTs and continental ice volume at glacial terminations. To reconcile divergent SST trends, we report reconstructions of two commonly used paleothermometers (the foraminifera G. ruber Mg/Ca and the alkenone unsaturation index) from a marine sediment core collected in the southwestern tropical Indian Ocean encompassing the last 37,000 years. Our results show that SSTs derived from the alkenone unsaturation index (U-37(K)) are consistently warmer than those derived from Mg/Ca by similar to 2-3 degrees C except for the Heinrich Event 1. In addition, the initial... |
Tipo: Text |
Palavras-chave: Sea surface temperature; Tropical Indian Ocean; Last Deglacial. |
Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00291/40174/39037.pdf |
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Roa Pascuali, Liliana; Demarcq, Herve; Nieblas, Anne-elise. |
In order to optimize frontal detection in sea surface temperature fields at 4 km resolution, a combined statistical and expert-based approach is applied to test different spatial smoothing of the data prior to the detection process. Fronts are usually detected at 1 km resolution using the histogram-based, single image edge detection (SIED) algorithm developed by Cayula and Cornillon in 1992, with a standard preliminary smoothing using a median filter and a 3 × 3 pixel kernel. Here, detections are performed in three study regions (off Morocco, the Mozambique Channel, and north-western Australia) and across the Indian Ocean basin using the combination of multiple windows (CMW) method developed by Nieto, Demarcq and McClatchie in 2012 which improves on the... |
Tipo: Text |
Palavras-chave: Mesoscale thermal fronts; Preliminary smoothing; Sea surface temperature; 4 km resolution; Gradient intensity classification; Expert-based approach; Detection efficiency; Indian Ocean. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00269/37998/42023.pdf |
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Reverdin, G.; Boutin, J.; Martin, N.; Lourenco, A.; Bouruet-aubertot, P.; Lavin, A.; Mader, J.; Blouch, P.; Rolland,; Gaillard, Fabienne; Lazure, Pascal. |
The accuracy of temperature measurements from drifters is first examined for 16 drifters (manufactured either by Metocean Data Systems or by Pacific Gyre) deployed with two temperature sensors in the tropical or North Atlantic Ocean. One of these sensors is the SST thermistor commonly used on Surface Velocity Program (SVP) drifters since the late 1980s; whereas the other sensor is a platinum temperature probe associated with a Seabird conductivity cell. The authors find (for 19 separate deployments) an average positive offset of the SST thermistor measurements in 17 out of 19 cases, exceeding 0.1 degrees C in five instances. Among the five drifters that were at sea for a year or more, two present a large trend in this offset (0.10 degrees and -0.10 degrees... |
Tipo: Text |
Palavras-chave: Temperature; Sea surface temperature; Instrumentation; Sensors. |
Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00012/12327/9112.pdf |
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Pahnke, K; Sachs, Jp. |
Late Quaternary climate fluctuated between extremes of glaciations, lasting similar to 90 kyr on average, and interglacial episodes, lasting similar to 10 kyr. Still largely unknown are the spatial and temporal evolution of these global climate states, with vigorous debate still underway on the mechanisms responsible for glacial inceptions and terminations. Though it is widely believed that the Southern Hemisphere oceans play a central role in global climate changes, few paleoclimate records exist from there. Here we present three new alkenone-derived SST records from the midlatitude Southern Hemisphere spanning the last 160 kyr, a full glacial-interglacial cycle. Our subtropical SST records from the last glacial period are characterized by ( 1) warming 47... |
Tipo: Text |
Palavras-chave: Sea surface temperature; Alkenone; Midsouthern latitudes. |
Ano: 2006 |
URL: https://archimer.ifremer.fr/doc/00234/34574/33121.pdf |
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Isern-fontanet, J.; Hascoet, Erwan. |
The noise present in infrared satellite measurements of sea surface temperature (SST) hampers the use of surface quasi-geostrophic (SQG) equations to diagnose ocean dynamics at high resolutions. Here we propose a methodology to reduce the contribution of noise when diagnosing surface vorticity, divergence, and vertical velocity from SST able to retain the dynamics at scales of a few kilometers. It is based on the use of denoising techniques with curvelets as basis functions and the application of a selective low-pass filters to improve the reconstruction of surface upwelling/downwelling patterns. First, it is tested using direct numerical simulations of SQG turbulence and then applied to diagnose low-frequency vertical velocity patterns from real MODIS... |
Tipo: Text |
Palavras-chave: Sea surface temperature; Surface quasi-geostrophy; Remote sensing; Vertical velocity; Ocean submesoscales; Image denoising. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00170/28162/26391.pdf |
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Small, David; Austin, William; Rinterknecht, Vincent. |
A sediment core from the north-east North Atlantic contains high-resolution co-registered foraminiferal O-18 and ice-rafted detritus (IRD) records for the last deglaciation. These reveal a distinct ice-rafting event that occurred at the time of Greenland Interstade 1d (GI-1d), a feature also seen in other high-resolution cores from the North Atlantic. The occurrence of a geographically widespread peak in IRD at ice distal sites at a time when increased freshwater flux to the surface ocean is inferred to have caused rapid cooling suggests a mechanistic link between the processes, analogous to the Younger Dryas (GS-1) cooling episode. The general absence of IRD at southern locations at other times during GI-1 when the flux of icebergs from surviving ice... |
Tipo: Text |
Palavras-chave: Deglaciation; Hydrography; Ice-rafted detritus; North Atlantic; Sea surface temperature. |
Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00291/40180/39238.pdf |
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Huret, Martin; Bourriau, Paul; Doray, Mathieu; Gohin, Francis; Petitgas, Pierre. |
Fishery annual surveys are shifting towards integrated ecosystem surveys. However, monitoring the whole ecosystem once a year entails special attention to the interpretation of observations, because they only represent a snapshot in the seasonal dynamics of the environment, of a species, or any dynamic process of interest. The dependency of this snapshot to the timing, but also to the duration, of the survey with respect to this seasonal dynamics needs to be considered. Fish stock assessment is only little impacted by the observed timing within a given season, whereas warming, stratification, plankton bloom occurrence, or fish fecundity, are processes rapidly changing especially in spring. Firstly, from independent satellite data, we described the seasonal... |
Tipo: Text |
Palavras-chave: Ecosystem survey; Anchovy; Sardine; Spawning; Sea surface temperature; Degree day; Bay of Biscay. |
Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00394/50584/51483.pdf |
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Harada, Naomi; Ninnemann, Ulysses; Lange, Carina B.; Marchant, Margarita E.; Sato, Miyako; Ahagon, Naokazu; Pantoja, Silvio. |
We show environmental and nitrogen cycle changes between 13 and 2.5 kyr BP (from the latest deglaciation to the Holocene) based on biogeochemical records in a sediment core from the Pacific entrance of the Strait of Magellan. Organic carbon, total nitrogen, and C-37 alkenone contents were low during 13-9 kyr BP but increased rapidly at 8 kyr BP. The relative contribution of tetra-unsaturated C-37 alkenone, used as a salinity proxy, suggests low salinity during 13-9 kyr BP changing to high salinity at 8 kyr BP. Planktic foraminifer data showed that Globigerina bulloides was more abundant during the deglacial-early Holocene than in the mid-late Holocene, whereas abundances of Neogloboquadrina pachyderma showed the opposite pattern. This evidence plus... |
Tipo: Text |
Palavras-chave: Biogenic components; Delta C-13; Delta N-15; Planktic foraminifera; Alkenone; Sea surface temperature; Southern Patagonia. |
Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00264/37548/36825.pdf |
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Nogueira Neto, A., V; Giordani, H.; Caniaux, G.; Araujo, M.. |
Oceanic and atmospheric processes were investigated in order to explore the causes of seasonal and interannual variability of sea surface temperatures (SST) in the western tropical Atlantic (WTA; 20 degrees S-20 degrees N, 15 degrees W-60 degrees W). A mixed-layer (ML) heat budget was performed by using Argo profiles and supplementary data sets based on satellite and atmospheric products during the period 2007-2012. The WTA is divided into four boxes which represent the main temporal and spatial heterogeneities of this region. An analysis of error of each term pointed out that the mean net surface heat fluxes are systematically underestimated by 20 W m(-2). A correction of this term provides realistic estimates of the vertical mixing which was obtained as... |
Tipo: Text |
Palavras-chave: Tropical Atlantic; Mixed-layer heat budget; Sea surface temperature; Argo floats. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00623/73551/73798.pdf |
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Conte, Mh; Sicre, Ma; Ruhlemann, C; Weber, Jc; Schulte, S; Schulz-bull, D; Blanz, T. |
[1] In this paper, we compile the current surface seawater C(37) alkenone unsaturation (U(37)(K')) measurements ( n = 629, - 1 to 30 degrees C temperature range) to derive a global, field-based calibration of U(37)(K') with alkenone production temperature. A single nonlinear "global'' surface water calibration of U(37)(K') accurately predicts alkenone production temperatures over the diversity of modern-day oceanic environments and alkenone-synthesizing populations (T = - 0.957 + 54.293(U(37)(K')) - 52.894(U(37)(K'))(2) + 28.321(U(37)(K'))(3), r(2) = 0.97, n = 567). The mean standard error of estimation is 1.2 degrees C with insignificant bias in estimated production temperature among the different ocean regions sampled. An exception to these trends is... |
Tipo: Text |
Palavras-chave: Alkenones; Paleoproxies; Sea surface temperature; UK ' 37. |
Ano: 2006 |
URL: https://archimer.ifremer.fr/doc/00239/34978/33474.pdf |
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Rouault, M.. |
PIRATA (Brazil, France, USA) has deployed between 1997 and 2001, an array of 12 ATLAS buoys with the objective of monitoring, describing and understanding the evolution of sea surface temperature, upper ocean thermal and saline structure, net heat budget, air-sea fluxes of momentum, latent and sensible heat and fresh water in the tropical Atlantic. The oceanic and meteorological observations are transmitted to shore via satellite and are available in near real-time on the Internet. They are communicated to the Global Telecommunication System and readily available for ocean and weather prediction models. The ultimate objective of PIRATA is real-time ocean monitoring to enable resource prediction in the adjacent countries. |
Tipo: Working Paper |
Palavras-chave: Buoys; Sea surface temperature; Saline water. |
Ano: 2003 |
URL: http://hdl.handle.net/1834/335 |
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Misra, V.. |
This study is an analysis of AGCM model results to understand the dynamics of the response of precipitation over southern Africa (SA) to anomalies in the sea surface temperature (SST) over the Pacific Ocean. The dipole pattern of interannual precipitation anomaly over SA and its temporal variations are quite similar in both the ensemble mean of the control (where the AGCM is forced with observed SST’s in all ocean basins) and experimental runs (where the AGCM is forced with seasonally varying climatological SST over the Pacific Ocean). However the amplitude of the variability is found to be relatively reduced in the experimental runs. This is shown to be a result of the modulation of the Walker circulation by the variability of Pacific Ocean SST. The... |
Tipo: Report |
Palavras-chave: Sea surface temperature; Precipitation (meteorology). |
Ano: 2002 |
URL: http://hdl.handle.net/1834/501 |
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Mahan, N. Claude; Bamba, S. Barthélémy; Aman, Angora. |
Depuis 1977, le Centre de Recherches Océanologiques (CRO) a entrepris des mesures quotidiennes de température de la mer le long des côtes ivoiriennes. Les remontées d'eaux froides qui affectent la côte ivoirienne présentent une forte variabilité à différentes échelles de temps et d'espace. Ces processus environnementaux complexes, irréguliers et difficiles à appréhender ont une grande influence sur un écosystème pélagique instable et par nature changeant (Arfi et al., 1995). Ces mesures répondent à un double objectif concernant l'étude saisonnière de l'upwelling côtier ivoiro-ghanéen pour prévoir les périodes et les zones favorables à la pêche sur le plateau continental ivoirien et à l'alimentation du projet GOOS (Global Ocean Observing System) de la... |
Tipo: Journal Contribution |
Palavras-chave: Sea surface temperature; Sea level variations; Inshore stations. |
Ano: 2008 |
URL: http://hdl.handle.net/1834/5748 |
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Registros recuperados: 69 | |
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