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Santiago de Compostela, Spain

Ramos-Soto A.,University of Santiago de Compostela | Bugarin A.J.,University of Santiago de Compostela | Barro S.,University of Santiago de Compostela | Taboada J.,Meteogalicia
IEEE Transactions on Fuzzy Systems | Year: 2015

We present in this paper an application that automatically generates textual short-term weather forecasts for every municipality in Galicia (NW Spain), using the real data provided by the GalicianMeteorology Agency (MeteoGalicia). This solution combines in an innovative way computing with perceptions techniques and strategies for linguistic description of data, together with a natural language generation (NLG) system. The application, which is named GALiWeather, extracts relevant information from weather forecast input data and encodes it into intermediate descriptions using linguistic variables and temporal references. These descriptions are later translated into natural language texts by the NLG system. The obtained forecast results have been thoroughly validated by an expert meteorologist from MeteoGalicia using a quality assessment methodology, which covers two key dimensions of a text: the accuracy of its content and the correctness of its form. Following this validation, GALiWeather will be released as a real service, offering custom forecasts for a wide public. © 2014 IEEE.

Lorenzo M.N.,University of Vigo | Iglesias I.,University of Vigo | Taboada J.J.,Meteogalicia | Gomez-Gesteira M.,University of Vigo
International Journal of Climatology | Year: 2010

This study assesses the relationship between monthly North Atlantic sea surface temperature anomalies (SSTAs) and a regional index of rainfall (NWIPR) in northwest Iberian Peninsula during the period 1951-2006 by means of the Pearson product-moment correlation. Results show a strong influence of SSTA on NWIPR in several months (February, April, May, October and December). The observed persistence of this influence up to 2-months in advance can be used for monthly predictions of rainfall. The most significant areas of the North Atlantic were clustered to be used as input variables in linear regression models. Correlations up to 0.59 between observed and predicted rainfall anomalies were obtained. Predictability ranged from 76 to 86% when considering rainfall as a discrete predictand. © 2009 Royal Meteorological Society.

Iglesias I.,University of Vigo | Iglesias I.,University of Porto | Lorenzo M.N.,University of Vigo | Taboada J.J.,Meteogalicia
PLoS ONE | Year: 2014

This study analyzes the influence of sea surface temperatures (SSTs) on the second mode of atmospheric variability in the north Atlantic/European sector, namely the East-Atlantic (EA) pattern, for the period 1950-2012. For this purpose, lead-lag relationships between SSTs and the EA pattern, ranging from 0 to 3 seasons, were assessed. As a main result, anomalies of the EA pattern in boreal summer and autumn are significantly related to SST anomalies in the Indo-Pacific Ocean during the preceding seasons. A statistical forecasting scheme based on multiple linear regression was used to hindcast the EA-anomalies with a lead-time of 1 to 2 months. The results of a one-year-out cross-validation approach indicate that the phases of the EA in summer and autumn can be properly hindcast. © 2014 Iglesias et al.

Perez-Munuzuri V.,Meteogalicia | Huhn F.,University of Santiago de Compostela
Nonlinear Processes in Geophysics | Year: 2010

Horizontal mixing has been found to play a crucial role in the development of spatial plankton structures in the ocean. We study the influence of time and length scales of two different horizontal two-dimensional (2-D) flows on the growth of a single phytoplankton patch. To that end, we use a coupled model consisting of a standard three component ecological NPZ model and a flow model able to mimic the mesoscale structures observed in the ocean. Two hydrodynamic flow models are used: a flow based on Gaussian correlated noise, for which the Eulerian length and time scales can be easily controlled, and a multiscale velocity field derived from altimetry data in the North Atlantic ocean. We find the optimal time and length scales for the Gaussian flow model favouring the plankton spread. These results are used for an analysis of a more realistic altimetry flow. We discuss the findings in terms of the time scale of the NPZ model, the qualitative interaction of the flow with the reaction front and a Finite-Time Lyapunov Exponent analysis.

Lorenzo M.N.,University of Vigo | Ramos A.M.,University of Vigo | Taboada J.J.,Meteogalicia | Gimeno L.,University of Vigo
PLoS ONE | Year: 2011

The aim of the work described herein was to study projection scenarios in order to find changes in the synoptic variability of the northwest Iberian Peninsula in the 21st century. To this end, we investigated the changes in the frequency of the different circulation types computed for the study area using three different models used in the IPCC 4th assessment report. The circulation types were computed using the procedure known as Lamb circulation types. The control simulation for the late 20th century was evaluated objectively from the results obtained using data from the NCEP/NCAR reanalysis, as to evaluate the ability of the model to reproduce the present climate. We have compared not only seasonal mean sea level pressure fields but also the mean seasonal frequency of circulation types. The results for the end of the 21st century show a decrease in the frequency of cyclonic, W, and SW circulation types in the spring and summer months. This trend also appears in the autumn, with a concomitant increase in the anticyclonic types. © 2011 Lorenzo et al.

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