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Freitas S.C.,Institute Meteorologia | Trigo I.F.,Institute Meteorologia | Trigo I.F.,Instituto Dom Luiz CGUL | Bioucas-Dias J.M.,University of Lisbon | Gottsche F.-M.,Karlsruhe Institute of Technology
IEEE Transactions on Geoscience and Remote Sensing | Year: 2010

Land surface temperature (LST) is estimated from thermal infrared data provided by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard Meteosat Second Generation (MSG), using a generalized split-window (GSW) algorithm. The uncertainty of the LST retrievals is highly dependent on the input accuracy and retrieval conditions, particularly the sensor view angle and the atmospheric water vapor content. This paper presents a quantification of the uncertainty of LST estimations, taking into account error statistics of the GSW under a globally representative collection of atmospheric profiles, and a careful characterization of the uncertainty of input data, particularly the surface emissivity and forecasts of the total water vapor content. Such analysis is the basis for LST uncertainty estimation, also distributed to users, in the form of error bars, along with the LST retrievals. Moreover, the spatial coverage of SEVIRI LST is essentially determined by the LST expected uncertainty, instead of being restricted to view zenith angles below a given threshold (e.g., 60°). Within the MSG disk, the atmosphere is often dry for clear-sky conditions where angles are large (e.g., Northern and Eastern Europe and Saudi Arabia). By considering several factors that contribute to LST inaccuracies, it is possible to increase the spatial coverage to regions such as those mentioned earlier. Retrieved values are also compared with in situ observations collected in Namibia, covering a seasonal cycle. The two data sets are in good agreement with root-mean-square differences ranging between 1 °C and 2 °C, which is well below the average error estimated for the satellite retrievals. © 2009 IEEE. Source

Agency: Cordis | Branch: FP7 | Program: CP | Phase: SPA-2007-1.1-01 | Award Amount: 32.56M | Year: 2008

geoland2 intends to constitute a major step forward in the implementation of the GMES Land Monitoring Core Service (LMCS). The three components (Local, Continental and Global) of the LMCS are addressed. The goal of geoland2 is (i) to prepare, validate and demonstrate pre-operational service chains and products that will underpin the LMCS, and (ii) to propose and demonstrate a concrete functional organisation of the LMCS. The geoland2 deliverables are : (i) the organisation of a production network, (ii) the building of operational processing lines, (iii), the demonstration of services and products, (iv), the set up of a land user platform. geoland2 efforts will rely on the assets of previous or ongoing projects funded under FP6 (geoland, Boss4GMES), by ESA (GSE projects Land, Forest Monitoring, GMFS, SAGE, Urban Services) and EEAs CLC/FTS 2006 project. The architecture of geoland2 is made of two different layers, the Core Mapping Services (CMS) and the Core Information Services (CIS). The CMS produce basic land cover, land cover change, and land state products which are of broad generic use and can be directly used for deriving more elaborated products. The CMS products cover a wide variety of thematic content, spatial scales from local to global, and update frequency, from 1 day to several years. The CIS are a set of thematic elements that start from CMS products and other data sources to produce elaborated information products addressing specific European policies. They are in direct contact with institutional end-users in charge of European policies and Member State policies which have a generic pan-European character. geoland2 gathers 51 partners from 21 European countries. The requested EC grant is 25 M, which corresponds to a total budget of approximately 37 M. The largest part of the budget allocation goes to the construction of the CMS.

Carrasco-Diaz M.,Institute Meteorologia | Carrasco-Diaz M.,Altamira | Rivas D.,CICESE | Orozco-Contreras M.,Altamira | Sanchez-Montante O.,Altamira
Renewable Energy | Year: 2015

Herein, we present an assessment of wind power potential along the coast of Tamaulipas, northeastern Mexico. We propose a method to characterize wind variability and to estimate wind potential in coastal areas where appropriate meteorological measurements may not be available. A gridded reanalysis wind product (BMW-CERSAT), which provides data of zonal and meridional components of wind with a resolution of 1/4°(~25km) from years 2004-2009, is used as the reference wind field after a statistical comparison to near-surface observations. Mean wind intensity field at 50-m height and its corresponding mean power density are modeled by using the Wind Atlas Analysis and Application Program (WAsP). The wind power potential of the southern half of Tamaulipas State is classified as poor (200-300Wm-2), becoming marginal in some areas near the coast. Only the northern half of the State is classified with moderate potential (400-500Wm-2), while the lagoon zone has good potential. Estimates, however, could be 30-50% higher if wind observations are measured at a higher frequency. Results show that the wind potential along Tamaulipas is lower than that suggested by the official prevailing eolic-potential map in Mexico. We conclude that even if the assessment presented in this work is preliminary, it gives a realistic approximation of wind as a promising renewable source for electric generation along the coast of Tamaulipas. © 2015 Elsevier Ltd. Source

Antunes S.,Institute Meteorologia | Pires O.,Associacao Portuguesa de Meteorologia e Geofisica | Rocha A.,University of Aveiro
International Journal of Climatology | Year: 2010

The North Atlantic mean sea level pressure field variability is analysed. A space-time study is performed using multichannel singular spectral analysis, allowing the detection of significant space-time modes of variability with periodicity behaviour. It is shown that there is a space variability associated with the time variability of the pressure field. The oscillation is not quasi-meridional but has different orientations, rotating in a cycle, with a periodicity of about 9 years, from the positive North Atlantic oscillation (NAO) phase through the negative NAO phase and again to the positive phase. This periodicity behaviour was previously detected in the temporal principal components extracted from a principal component analysis but, in the time domain, it was found as not significant. Furthermore, the analysis of a long series of an NAO index had already revealed similar periodicity behaviour. © 2009 Royal Meteorological Society. Source

Carrer D.,Meteo - France | Lafont S.,Meteo - France | Roujean J.-L.,Meteo - France | Calvet J.-C.,Meteo - France | And 3 more authors.
Journal of Hydrometeorology | Year: 2012

The Land Surface Analysis Satellite Applications Facility (LSA SAF) project radiation fluxes, derived from the Meteosat Second Generation (MSG) geostationary satellite, were used in the Interactions between Soil, Biosphere, and Atmosphere (ISBA) land surface model (LSM), which is a component of the Surface Externalisée (SURFEX) modeling platform. The Syste'me d'Analyze Fournissant des Renseignements Atmosphériques a' la Neige (SAFRAN) atmospheric analysis provides high-resolution atmospheric variables used to drive LSMs over France. The impact of using the incoming solar and infrared radiation fluxes [downwelling surface shortwave (DSSF) and longwave (DSLF), respectively] from either SAFRAN or LSA SAF, in ISBA, was investigated over France for 2006. In situ observations from the FluxNetwork (FLUXNET) were used for the verification. Daily differences between SAFRAN and LSA SAF radiation fluxes averaged over the whole year 2006 were 3.75 and 2.61 W m -2 for DSSF and DSLF, respectively, representing 2.5% and 0.8% of their average values. The LSA SAF incoming solar radiation presented a better agreement with in situ measurements at six FLUXNET stations than the SAFRAN analysis. The bias and standard deviation of differences were reduced by almost 50%. The added value of the LSA SAF products was assessed with the simulated surface temperature, soil moisture, and the water and energy fluxes. The latter quantities were improved by the use of LSA SAF satellite estimates. As many areas lack a high-resolution meteorological analysis, the LSA SAF radiative products provide new and valuable information. © 2012 American Meteorological Society. Source

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