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© 2010 American Meteorological Society. The National Center for Atmospheric Research is sponsored by the National Science Foundation.This project was accomplished within the Collaboration Agreement 09/153 between UCM and CIEMAT, and it was partially funded by Project CGL2005-06966-C07/CLI. We thank the Navarra Government for providing us with the wind dataset used in this study and ECMWF for free access to its datasets. An initial version of the wavelet software was provided by C. Torrence and G. Compo (available online at http:// atoc.colorado.edu/research/). We also thank the three reviewers for their helpful comments., This study analyzes the daily-mean surface wind variability over an area characterized by complex topography through comparing observations and a 2-km-spatial-resolution simulation performed with the Weather Research and Forecasting (WRF) model for the period 1992-2005. The evaluation focuses on the performance of the simulation to reproduce the wind variability within subregions identified from observations over the 1999-2002 period in a previous study. By comparing with wind observations, the model results show the ability of the WRF dynamical downscaling over a region of complex terrain. The higher spatio-temporal resolution of the WRF simulation is used to evaluate the extent to which the length of the observational period and the limited spatial coverage of observations condition one's understanding of the wind variability over the area. The subregions identified with the simulation during the 1992-2005 period are similar to those identified with observations (1999-2002). In addition, the reduced number of stations reasonably represents the spatial wind variability over the area. However, the analysis of the full spatial dimension simulated by the model suggests that observational coverage could be improved in some subregions. The approach adopted here can have a direct application to the design of observational networks., National Science Foundation (NSF), Universidad Complutense de Madrid (UCM), Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© 2012 American Meteorological Society. This investigation was partially supported by Projects CGL-2008-05093/CLI and CGL-2011-29677-C02 and was accomplished within the Collaboration Agreement 09/490 between CIEMAT and NCAR as well as the Collaboration Agreement 09/153 between CIEMAT and UCM. NCAR is sponsored by the National Science Foundation. We thank the Navarra government for providing us with the observations used in this study. Discussion with Fei Chen and Peggy Lemone were helpful during this work. The authors would also like to thank Maria Tombrou for her comments regarding the similarity functions in unstable conditions. We would also like to thank the reviewers for their constructive comments., This study summarizes the revision performed on the surface layer formulation of the Weather Research and Forecasting (WRF) model. A first set of modifications are introduced to provide more suitable similarity functions to simulate the surface layer evolution under strong stable/unstable conditions. A second set of changes are incorporated to reduce or suppress the limits that are imposed on certain variables in order to avoid undesired effects (e. g., a lower limit in u_*). The changes introduced lead to a more consistent surface layer formulation that covers the full range of atmospheric stabilities. The turbulent fluxes are more (less) efficient during the day (night) in the revised scheme and produce a sharper afternoon transition that shows the largest impacts in the planetary boundary layer meteorological variables. The most important impacts in the near-surface diagnostic variables are analyzed and compared with observations from a mesoscale network., National Science Foundation (NSF), Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Universidad Complutense de Madrid (UCM), National Center for Atmospheric Research (NCAR), Depto. de Física Teórica, Fac. de Ciencias Físicas, TRUE, pub

© 2010 American Meteorological Society. This project was accomplished within the collaboration agreement 091153 between UCM and CIEMAT, and it was partially funded by projects CGL2005-06966-C07/CLI and PSE-120000-2008-9 We thank the Navarra Government for providing us with the wind dataset used in this study. We also like to thank the reviewers for their helpful comments., Meteorological data of good quality arc important for understanding both global and regional climates In this respect, great efforts have been made to evaluate temperature- and precipitation-related records This study summarizes the evaluations made to date of the quality of wind speed and direction records acquired at 41 automated weather stations in the northeast of the Iberian Peninsula Observations were acquired from 1992 to 2005 at a temporal resolution of 10 and 30 min A quality assurance system was imposed to select) the records for 1) manipulation errors associated with storage and management of the data. 2) consistency limits to to ensure that observations ale within their natural limits of variation, and 3) temporal consistency to assess abnormally low/high variations in the individual time series In addition. the most important biases of the dataset are analyzed and corrected wherever possible A total of 1 8% wind speed and 3 7% wind direction records was assumed invalid. pointing to specific problems in wind measurement The study not only tiles to contribute to the science with the creation of a wind damsel of unmoved quality. but it also reports on potential errors that could be plc:sent in other wind datasets, Universidad Complutense de Madrid (UCM), Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© 2011 American Meteorological Society. The National Center for Atmospheric Research is sponsored by the National Science Foundation.We thank the Navarra government and the ECMWF for providing us with the datasets used in this study. This investigation was partially supported by Projects CGL-2008-05093/CLI and PSE-120000-2008-9 and was accomplished within the Collaboration Agreement 09/490 between CIEMAT and NCAR as well as the Collaboration Agreement 09/153 between CIEMAT and UCM. We also thank the reviewers for their helpful comments., Variations in the diurnal wind pattern associated with heat waves and drought conditions are investigated climatologically at a regional level (northeast of the Iberian Peninsula). The study, based on high-density observational evidence and fine spatial-scale mesoscale modeling for the 1992-2004 period, shows that wind speed can decrease up to 22% under situations characterized by extremely high temperatures and severe drought, such as the European summer of 2003. By examining the role of the different atmospheric scales of motion that determine the wind diurnal variability, it is found that the 2003 synoptic conditions are the main driver for changes in the wind speed field. In turn, these changes are modulated by mesoscale circulations influenced by the soil moisture availability. The results have implications for broad regional modeling studies of current climate and climate change simulations in as much as the study demonstrates that a correct representation of local soil moisture conditions impacts atmospheric circulation and therefore the regional climate state., National Science Foundation, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), España, National Center for Atmospheric Research (NCAR), EE.UU., Universidad Complutense de Madrid (UCM), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© by Gebrüder Borntraeger 2010. Lund Regional-Scale Climate Modelling Workshop (2nd. 2009. Lund, Sweden). This work was funded by the Spanish Ministry of the Environment (project ESCENA, Ref. 20080050084265) and the Spanish Ministry of Science and Technology (project INVENTO -CGL2005-06966-C07-04/CLI). The authors also gratefully acknowledge the funding from the Euro-Mediterranean Institute of Water (IEA). Thanks to Christina SCHWARZ for the abstract translation., Three different Land Surface Models have been used in three high resolution climate simulations performed with the mesoscale model MM5 over the Iberian Peninsula. The main difference among them lies in the soil moisture treatment, which is dynamically modelled by only two of them (Noah and Pleim & Xiu models), while in the simplest model (Simple Five-Layers) it is fixed to climatological values. The simulated period covers 1958-2002, using the ERA40 reanalysis data as driving conditions. Focusing on near-surface air temperature, this work evaluates the skill of each simulation in reproducing mean values and temporal variability, by comparing the simulations with observed temperature series. When the simplest simulation was analyzed, the greatest discrepances were observed for the summer season, when both, the mean values and the temporal variability of the temperature series, were badly underestimated. These weaknesses are largely overcome in the other two simulations (performed by coupling a more advanced soil model to MM5), and there was greater concordance between the simulated and observed spatial patterns. The influence of a dynamic soil moisture parameterization and, therefore, a more realistic simulation of the latent and sensible heat fluxes between the land and the atmosphere, helps to explain these results., Drei verschiedene Landoberflächenmodelle wurden verwendet, um drei hochauflösende Klimasimulationen für die iberische Halbinsel mit Hilfe des mesoskaligen Modells MM5 durchzuführen. Der Unterschied der drei Modelle liegt hauptsächlich in der Behandlung der Bodenfeuchtigkeit, die in zwei der Modelle (Noah und Pleim & Xiu) dynamisch modelliert wird, während sie im einfachsten Modell (Simple Five-Layers) durch klimatologische Größen festgelegt ist. Die simulierte Zeitspanne reicht von 1958 bis 2002, wobei als Simulationsbedingungen die Reanalyse-Daten ERA40 dienen. Indem wir uns auf bodennahe Lufttemperaturen konzentrieren, wird in dieser Arbeit die Qualität jeder einzelnen Simulation, welche die beobachteten Jahreszyklen, die räumlichen Strukturen und die zeitlichen Veränderungen der Temperatur wiedergibt, durch den Vergleich mit instrumentellenMonatsmitteltemperaturserien ausgewertet. Die einfachste Simulation zeigt die größte Diskrepanz zu den Beobachtungen der Sommersaison, da die Temperaturmittel und die zeitlichen Veränderungen der Temperatur maßgeblich unterschätzt wurden. Diese Schwächen wurden in den beiden anderen Simulationen (in denen ein fortschrittlicheres Bodenmodell an MM5 gekoppelt wurde) zum größten Teil beseitigt und eine höhere übereinstimmung zwischen simulierten und beobachteten räumlichen Strukturen wurde erreicht. Der Einfluss einer dynamischen Bodenfeuchtigkeitsparametrisierung und dadurch eine realistischere Simulation des latenten Flusses und der Wärmestromdichte zwischen Boden und Atmosphäre begr ünden diese Ergebnisse weitgehend., Ministerio de Medio Ambiente (MMA), España, Ministerio de Ciencia y Tecnología (MCYT), España, Euro-Mediterranean Institute of Water (IEA), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub