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El presente trabajo de investigación aborda el estudio de la influencia del viento en la variabilidad espacio-temporal de la circulación del Estrecho de Gibraltar (sur de la Península Ibérica) y de las respuestas inducidas que se producen en las fluctuaciones barotrópicas y del intercambio baroclino, mediante un modelo oceánico forzado por viento. Para ello, se ha implementado el modelo atmosférico MM5 de área limitada no hidrostático, el cual provee el campo de viento a alta resolución al modelo hidrodinámico, bicapa, bidimensional, no-lineal UCA2.5D, que utiliza coordenadas curvilíneas ajustadas a los contornos y que incluye el forzamiento de marea. La capacidad del modelo MM5 para reproducir los patrones mesoescalares meteorológicos en la compleja orografía de la región andaluza, así como las brisas de tierra-mar y montaña-valle ha sido evaluada satisfactoriamente. No obstante, existen algunas diferencias entre las simulaciones y las observaciones atribuidas a distintas causas, las cuales han sido discutidas. Del mismo modo, las salidas del modelo oceánico, forzado por viento, han sido comparadas frente a un amplio conjunto de datos oceanográficos, mostrando una mejora significativa frente al modelo hidrodinámico forzado únicamente por marea. Los resultados evidencian la importancia del efecto del viento en la dinámica del Estrecho de Gibraltar. Los vientos del este o Levantes (del oeste o Ponientes) originan un hundimiento (surgencia) en la costa española del Estrecho, dando lugar a un incremento (reducción) del espesor de la capa atlántica, profundizando (elevando) la interfaz y elevando (hundiendo) el nivel del mar. La acumulación de agua en la costa norte (sur) del Estrecho en eventos de viento de Levante (Poniente) intenso y persistente, crea una diferencia de nivel en la sección transversal, dando lugar a una corriente geostrófica hacia el oeste (este). Esta corriente, en el caso de los Levantes, refuerza la contracorriente costera semipermanente de la cost, This research work makes an incremental step in understanding the role of the wind-stress and the associated dynamic ocean response of the barotropic and baroclinic exchange fluctuations by means of a wind-forced ocean model within the Strait of Gibraltar (south of Iberian Peninsula). The limited-area, non-hydrostatic atmospheric model MM5 was configured to study the mesoscale atmospheric processes in the area of interest and to provide realistic wind-stress forcing to the two-layer, two-dimensional, nonlinear, boundary-fitted coordinate hydrostatic model UCA2.5D at high-resolution, also forced by tidal motions. A statistical evaluation of the MM5 model performance is undertaken by means of pairwise comparison of observations and model output, showing good skills in reproducing the mesoscale flows over the complex Andalusian orography, sea-land breeze circulation and mountain-valley breezes. However, some discrepancies between observations and predictions have been found and their main causes have been discussed. Most importantly, comparison of model results with an extensive oceanographic data set collected in situ shows that the wind-forced ocean model provides better agreement with the observations than the ocean-alone model with tidal forcing. Results show the effect of winds on the dynamics in the Strait of Gibraltar with and without tidal forcing, pointing out the essential sensitivity of the area to different forcings. The hydrodynamic patterns induced by wind stress are successfully simulated showing that prevailing easterly (westerly) winds originate downwelling (upwelling) phenomena in the Spanish coast of the Strait of Gibraltar, which subsequently will induce an increase (reduction) of the upper layer thickness, deepening (rising up) the interface and rising (dropping) the sea level. During persistent and intense easterly (westerly) wind episodes, the accumulation of water in the northern (southern) part reduces (reinforces) the downwards south-to-north

El presente trabajo de investigación aborda el estudio de la influencia del viento en la variabilidad espacio-temporal de la circulación del Estrecho de Gibraltar (sur de la Península Ibérica) y de las respuestas inducidas que se producen en las fluctuaciones barotrópicas y del intercambio baroclino, mediante un modelo oceánico forzado por viento. Para ello, se ha implementado el modelo atmosférico MM5 de área limitada no hidrostático, el cual provee el campo de viento a alta resolución al modelo hidrodinámico, bicapa, bidimensional, no-lineal UCA2.5D, que utiliza coordenadas curvilíneas ajustadas a los contornos y que incluye el forzamiento de marea. La capacidad del modelo MM5 para reproducir los patrones mesoescalares meteorológicos en la compleja orografía de la región andaluza, así como las brisas de tierra-mar y montaña-valle ha sido evaluada satisfactoriamente. No obstante, existen algunas diferencias entre las simulaciones y las observaciones atribuidas a distintas causas, las cuales han sido discutidas. Del mismo modo, las salidas del modelo oceánico, forzado por viento, han sido comparadas frente a un amplio conjunto de datos oceanográficos, mostrando una mejora significativa frente al modelo hidrodinámico forzado únicamente por marea. Los resultados evidencian la importancia del efecto del viento en la dinámica del Estrecho de Gibraltar. Los vientos del este o Levantes (del oeste o Ponientes) originan un hundimiento (surgencia) en la costa española del Estrecho, dando lugar a un incremento (reducción) del espesor de la capa atlántica, profundizando (elevando) la interfaz y elevando (hundiendo) el nivel del mar. La acumulación de agua en la costa norte (sur) del Estrecho en eventos de viento de Levante (Poniente) intenso y persistente, crea una diferencia de nivel en la sección transversal, dando lugar a una corriente geostrófica hacia el oeste (este). Esta corriente, en el caso de los Levantes, refuerza la contracorriente costera semipermanente de la cost, This research work makes an incremental step in understanding the role of the wind-stress and the associated dynamic ocean response of the barotropic and baroclinic exchange fluctuations by means of a wind-forced ocean model within the Strait of Gibraltar (south of Iberian Peninsula). The limited-area, non-hydrostatic atmospheric model MM5 was configured to study the mesoscale atmospheric processes in the area of interest and to provide realistic wind-stress forcing to the two-layer, two-dimensional, nonlinear, boundary-fitted coordinate hydrostatic model UCA2.5D at high-resolution, also forced by tidal motions. A statistical evaluation of the MM5 model performance is undertaken by means of pairwise comparison of observations and model output, showing good skills in reproducing the mesoscale flows over the complex Andalusian orography, sea-land breeze circulation and mountain-valley breezes. However, some discrepancies between observations and predictions have been found and their main causes have been discussed. Most importantly, comparison of model results with an extensive oceanographic data set collected in situ shows that the wind-forced ocean model provides better agreement with the observations than the ocean-alone model with tidal forcing. Results show the effect of winds on the dynamics in the Strait of Gibraltar with and without tidal forcing, pointing out the essential sensitivity of the area to different forcings. The hydrodynamic patterns induced by wind stress are successfully simulated showing that prevailing easterly (westerly) winds originate downwelling (upwelling) phenomena in the Spanish coast of the Strait of Gibraltar, which subsequently will induce an increase (reduction) of the upper layer thickness, deepening (rising up) the interface and rising (dropping) the sea level. During persistent and intense easterly (westerly) wind episodes, the accumulation of water in the northern (southern) part reduces (reinforces) the downwards south-to-north

Ground-level ozone is a secondary pollutant that causes serious health and environmental damage. One of the main challenges in controlling ground-level ozone is to identify the categories of ozone precursor species that contribute the most to ozone levels, and the regions from which they are emitted. In this study, we apply a photochemical model source apportionment tool to identify the contributions of various precursors to seasonal ozone levels in Hong Kong (HK) and the Pearl River Delta (PRD) region, according to their source regions and categories. We establish a full precursor contribution matrix for the ozone concentrations in all cities within the HK/PRD region. This matrix can be used to rank the relative importance of precursors by source region/category for each city. It can also be used to show how the precursor emissions from any city/category affect ozone levels in neighboring cities. The results show substantial seasonal variation in the source contributions from the HK/PRD region. During ozone episodes, precursors from the region accounted for 68-80% of ozone concentrations in July and 35-55% in October, but only 19-32% in January and April. For all of the cities in the PRD, the top three precursor categories contributing to ozone episodes were mobile, point and area sources. Biogenic and point sources were more important in July than in October. In contrast, the ranking of contributing source regions showed considerable variation across cities and seasons, implying substantial variations in the ways in which precursors from one city affect ozone levels in neighboring cities. Our results show that source contribution and impact analysis can be very useful for evaluating the ozone control strategies of local governments. For the PRD region, a local reduction in mobile, area and point sources, together with regional collaborations on pollution control, are of particular importance in effectively reducing episodic ozone concentrations. (C) 2013 Elsevier

Ground-level ozone is a secondary pollutant that causes serious health and environmental damage. One of the main challenges in controlling ground-level ozone is to identify the categories of ozone precursor species that contribute the most to ozone levels, and the regions from which they are emitted. In this study, we apply a photochemical model source apportionment tool to identify the contributions of various precursors to seasonal ozone levels in Hong Kong (HK) and the Pearl River Delta (PRD) region, according to their source regions and categories. We establish a full precursor contribution matrix for the ozone concentrations in all cities within the HK/PRD region. This matrix can be used to rank the relative importance of precursors by source region/category for each city. It can also be used to show how the precursor emissions from any city/category affect ozone levels in neighboring cities. The results show substantial seasonal variation in the source contributions from the HK/PRD region. During ozone episodes, precursors from the region accounted for 68-80% of ozone concentrations in July and 35-55% in October, but only 19-32% in January and April. For all of the cities in the PRD, the top three precursor categories contributing to ozone episodes were mobile, point and area sources. Biogenic and point sources were more important in July than in October. In contrast, the ranking of contributing source regions showed considerable variation across cities and seasons, implying substantial variations in the ways in which precursors from one city affect ozone levels in neighboring cities. Our results show that source contribution and impact analysis can be very useful for evaluating the ozone control strategies of local governments. For the PRD region, a local reduction in mobile, area and point sources, together with regional collaborations on pollution control, are of particular importance in effectively reducing episodic ozone concentrations. (C) 2013 Elsevier

Ground-level ozone is a secondary pollutant that causes serious health and environmental damage. One of the main challenges in controlling ground-level ozone is to identify the categories of ozone precursor species that contribute the most to ozone levels, and the regions from which they are emitted. In this study, we apply a photochemical model source apportionment tool to identify the contributions of various precursors to seasonal ozone levels in Hong Kong (HK) and the Pearl River Delta (PRD) region, according to their source regions and categories. We establish a full precursor contribution matrix for the ozone concentrations in all cities within the HK/PRD region. This matrix can be used to rank the relative importance of precursors by source region/category for each city. It can also be used to show how the precursor emissions from any city/category affect ozone levels in neighboring cities. The results show substantial seasonal variation in the source contributions from the HK/PRD region. During ozone episodes, precursors from the region accounted for 68-80% of ozone concentrations in July and 35-55% in October, but only 19-32% in January and April. For all of the cities in the PRD, the top three precursor categories contributing to ozone episodes were mobile, point and area sources. Biogenic and point sources were more important in July than in October. In contrast, the ranking of contributing source regions showed considerable variation across cities and seasons, implying substantial variations in the ways in which precursors from one city affect ozone levels in neighboring cities. Our results show that source contribution and impact analysis can be very useful for evaluating the ozone control strategies of local governments. For the PRD region, a local reduction in mobile, area and point sources, together with regional collaborations on pollution control, are of particular importance in effectively reducing episodic ozone concentrations. (C) 2013 Elsevier

Benzo(a)pyrene (BaP) is polycyclic aromatic hydrocarbon whose adverse effects on human health have been demonstrated. Directive 2004/107/CE of the European Union establishes a target value of 1 ng/m3 of BaP in the atmosphere. In this contribution we have used the third generation of air quality modelling systems to evaluate the impact of BaP emissions in Zaragoza area (Spain) with 1 km spatial resolution. We have developed the inclusion of the transport, scavenging and deposition processes for the BaP. BaP degradation and adsorption mechanism have also been integrated into the chemical-transport model CMAQ (Community Multiscale Air Quality Modelling System). BaP is injected into the atmosphere as particle.The aerosol-gas partitioning phenomenon in the atmosphere is modelled taking into a count that the concentrations in the gas and the aerosol phases are in equilibrium. The WRF (Weather Research & Forecasting Model)) is also used to provide the meteorological information as input for CMAQ modelling system. A validation process of the BaP and other pollutant results have been conducted in the urban area of Zaragoza (Spain) during 12 weeks since February, 2010 to January, 2011. The agreement is generally satisfactory.

As mesoscale models increase in resolution there is a greater need to understand predictability on smaller scales. The predictability of a model is related to forecast skill. It is possible that the uncertainty of one scale of motion can affect the other scales due to the nonlinearity of the atmosphere. Some suggest that topography is one factor that can lead to an increase of forecast skill and therefore predictability. This study examines the uncertainty of a mesoscale model and attempts to characterize the predictability of the wind field. The data collected is from the summer, when the synoptic forcing is relatively benign. Mesoscale Model 5 (MM5) lagged forecasts are used to create a three-member ensemble over a 12-hour forecast cycle. The differences in these forecasts are used to determine the spread of the wind field. Results show that some mesoscale features have high uncertainty and others have low uncertainty, shedding light on the potential predictability of these features with a mesoscale model. Results indicate that topography is a large source of uncertainty. This is seen in all data sets, contrary to other studies. The ability of the model to properly forecast the diurnal cycle also impacted substantially on the character and evolution of forecast spread. The persistent mesoscale features were represented reasonably well, however the detailed structure of these features had a fair amount of uncertainty., http://archive.org/details/anumericalinvest109451145, Lieutenant Junior Grade, United States Navy, Approved for public release; distribution is unlimited.

Vertical profiles of particle number concentration, potential temperature and relative humidity were measured in the Po Valley using an optical particle counter and a portable meteorological station attached to a tethered balloon. The field campaign covered the period 2006-2008, providing an extended dataset of vertical profiles in both stable and convective boundary-layer conditions. These vertical profiles were used to estimate an experimentally retrieved mixing height (MH).The MM5 meteorological model was also used to simulate the atmospheric dispersion characteristics for the same period, using a variety of different boundary-layer and land surface parameterization schemes (Medium-Range Forecast; high-resolution Blackadar; Gayno-Seaman; and Pleim-Chang). The model simulated MHs were compared among themselves, and then with that measured from balloon soundings. MRF parameterization represented the best compromise solution to simulate increasing MHs in the Po Valley. The MM5 simulations showed the regional character of meteorological forcing on PM ground-concentrations in the Po Valley

This work investigates the impact of assimilating water vapor Light Detection and Ranging (lidar) data into mesoscale Numerical Weather Prediction (NWP) models. Two cases from the field campaigns International H20 Project 2002 (IHOP_2002) and International Lindenberg Campaign for Assessment of Humidity- and Cloud-Profiling Systems and its Impact on High-Resolution Modelling 2005 (LAUNCH-2005) are presented. In the first case, airborne water vapor Differential Absorption Lidar (DIAL) data are used for an assimilation for 24 May 2002, where convection occurred along an eastward moving dryline in western Texas and Oklahoma south of a triple point that formed in western Oklahoma. In the second case, a network of three ground based water vapor Raman lidars, operated behind a sharp frontal rain band with a northwesterly flow, are used. The method employed, Four-Dimensional Variational Data Assimilation (4D-Var), is described in relation to other methods and the implementation is given in detail. The data assimilation results in a large modification of the initial fields. The assimilation into the preconvective conditions changed not only the water vapor field but also the location of convergence lines, causing positive modification of Convective Initiation (CI). In the LAUNCH-2005 case a strong correction of the vertical structure and the absolute values of the initial water-vapor field of the order of 1g/kg was found. This occurred mainly upstream of the lidar systems within an area that was comparable with the domain covered by the lidar systems. The correction of the water-vapor field was validated using independent Global Positioning System (GPS) sensors. Much better agreement with GPS zenith wet path delay was achieved with the initial water-vapor field after 4D-Var. Furthermore, the impact of the assimilation and its temporal evolution was investigated with introduced measures. The results demonstrate the high value of accurate vertically resolved mesoscale water va, Diese Arbeit untersucht die Auswirkungen der Assimilation von Wasserdampf Light Detection and Ranging (Lidar)-Daten in mesoskalige numerische Wettervorhersagemodelle (NWP). Zwei Fallstudien aus den Feldkampagnen International H2O Project 2002 (IHOP_2002) und International Lindenberg Campaign for Assessment of Humidity- and Cloud-Profiling Systems and its Impact on High-Resolution Modelling 2005 (LAUNCH-2005) werden vorgestellt. Im ersten Fall wurden flugzeuggestützte Differential Absorption Lidar (DIAL)-Wasserdampf-Daten für eine Assimilation am 24. Mai 2002 genutzt. An diesem Tag trat Konvektion entlang einer sich ostwärts bewegenden Feuchtefront im Westen Texas und in Oklahoma, südlich eines Tripelpunkt, auf. Im zweiten Fall wurde ein Netzwerk von drei bodengestützten Wasserdampf-Raman-Lidar-Systemen benutzt, welches nach Durchzug eines Regenbandes entlang einer Front und bei nordwestlichem Wind betrieben wurde. Die verwendete Methode, Four-Dimensional Variational Data Assimilation (4D-Var), wird erläutert und mit anderen Datenassimilationsmethoden verglichen, wobei die hierfür notwendigen Implementationen detailliert beschrieben werden. Die Datenassimilation hat eine große Änderung der Anfangsbedingungen zur Folge. Die Assimilation in die prekonvektiven Bedingungen veränderte nicht nur die Verteilung des Wasserdampfes, sondern auch die Lage von Konvergenzlinien, was die Auslösung von Konvektion (CI) positiv modifizierte. Im LAUNCH-2005 Fall wurde eine starke Korrektur der vertikalen Struktur und der absoluten Menge des initialen Wasserdampfes in der Größenordnung von 1g/kg festgestellt. Dies trifft hauptsächlich auf Gebiete im Lee der Lidar-Systeme zu. Die Korrektur des Wasserdampffeldes wurde mit unabhängigen Global Positioning System (GPS)-Messungen validiert. Durch die 4D-Var wurde eine bessere Übereinstimmung des Wasserdampf-Anfangsfeldes mit GPS Zenit Wet Path Delay (ZWD) erreicht. Außerdem wurde die Auswirkung der Assimilation und die weitere zeitlicher Ver

Se presenta la comparación de las salidas del modelo MM5 con datos tomados in situ en la Isla del Coco, Costa Rica. Las observaciones fueron realizadas en tres expediciones hechas a la isla en octubre del 2007, abril del 2008 y marzo del 2009. Para ejecutar las simulaciones se utilizaron las salidas del modelo de tiempo atmósferico del National Center for Environmental Prediction (NCEP), que inició a las 00 UTC y se empleó la retroalimentación dinámica en ambas direcciones. Se configuraron cuatro dominios de 90, 30, 10 y 3,3 km (42 x 47, 76 x 85, 100 x 121, 73 x 73 puntos) con 35 niveles en la vertical y con pronósticos de hasta 48 horas, cada tres horas. Se encontró que con las configuraciones físicas elegidas se realiza una mejor representación de los periodos húmedos que de los periodos con mayor precipitación en dicha zona. Tales resultados se manifiestan en las predicciones de humedad relativa y precipitación, lo que confirma la relación entre estas dos variables en la zona. Sin embargo, no se encontró una adecuada simulación de los patrones de radiación de onda corta incidente. La temperatura ha mostrado valores acordes con otros experimentos, mientras que el viento presentó una mejor simulación en los niveles medios que en capa límite.

Se presenta la comparación de las salidas del modelo MM5 con datos tomados in situ en la Isla del Coco, Costa Rica. Las observaciones fueron realizadas en tres expediciones hechas a la isla en octubre del 2007, abril del 2008 y marzo del 2009. Para ejecutar las simulaciones se utilizaron las salidas del modelo de tiempo atmósferico del National Center for Environmental Prediction (NCEP), que inició a las 00 UTC y se empleó la retroalimentación dinámica en ambas direcciones. Se configuraron cuatro dominios de 90, 30, 10 y 3,3 km (42 x 47, 76 x 85, 100 x 121, 73 x 73 puntos) con 35 niveles en la vertical y con pronósticos de hasta 48 horas, cada tres horas. Se encontró que con las configuraciones físicas elegidas se realiza una mejor representación de los periodos húmedos que de los periodos con mayor precipitación en dicha zona. Tales resultados se manifiestan en las predicciones de humedad relativa y precipitación, lo que confirma la relación entre estas dos variables en la zona. Sin embargo, no se encontró una adecuada simulación de los patrones de radiación de onda corta incidente. La temperatura ha mostrado valores acordes con otros experimentos, mientras que el viento presentó una mejor simulación en los niveles medios que en capa límite.

Se presenta la comparación de las salidas del modelo MM5 con datos tomados in situ en la Isla del Coco, Costa Rica. Las observaciones fueron realizadas en tres expediciones hechas a la isla en octubre del 2007, abril del 2008 y marzo del 2009. Para ejecutar las simulaciones se utilizaron las salidas del modelo de tiempo atmósferico del National Center for Environmental Prediction (NCEP), que inició a las 00 UTC y se empleó la retroalimentación dinámica en ambas direcciones. Se configuraron cuatro dominios de 90, 30, 10 y 3,3 km (42 x 47, 76 x 85, 100 x 121, 73 x 73 puntos) con 35 niveles en la vertical y con pronósticos de hasta 48 horas, cada tres horas. Se encontró que con las configuraciones físicas elegidas se realiza una mejor representación de los periodos húmedos que de los periodos con mayor precipitación en dicha zona. Tales resultados se manifiestan en las predicciones de humedad relativa y precipitación, lo que confirma la relación entre estas dos variables en la zona. Sin embargo, no se encontró una adecuada simulación de los patrones de radiación de onda corta incidente. La temperatura ha mostrado valores acordes con otros experimentos, mientras que el viento presentó una mejor simulación en los niveles medios que en capa límite.

Se presenta la comparación de las salidas del modelo MM5 con datos tomados in situ en la Isla del Coco, Costa Rica. Las observaciones fueron realizadas en tres expediciones hechas a la isla en octubre del 2007, abril del 2008 y marzo del 2009. Para ejecutar las simulaciones se utilizaron las salidas del modelo de tiempo atmósferico del National Center for Environmental Prediction (NCEP), que inició a las 00 UTC y se empleó la retroalimentación dinámica en ambas direcciones. Se configuraron cuatro dominios de 90, 30, 10 y 3,3 km (42 x 47, 76 x 85, 100 x 121, 73 x 73 puntos) con 35 niveles en la vertical y con pronósticos de hasta 48 horas, cada tres horas. Se encontró que con las configuraciones físicas elegidas se realiza una mejor representación de los periodos húmedos que de los periodos con mayor precipitación en dicha zona. Tales resultados se manifiestan en las predicciones de humedad relativa y precipitación, lo que confirma la relación entre estas dos variables en la zona. Sin embargo, no se encontró una adecuada simulación de los patrones de radiación de onda corta incidente. La temperatura ha mostrado valores acordes con otros experimentos, mientras que el viento presentó una mejor simulación en los niveles medios que en capa límite.

This work investigates the impact of assimilating water vapor Light Detection and Ranging (lidar) data into mesoscale Numerical Weather Prediction (NWP) models. Two cases from the field campaigns International H20 Project 2002 (IHOP_2002) and International Lindenberg Campaign for Assessment of Humidity- and Cloud-Profiling Systems and its Impact on High-Resolution Modelling 2005 (LAUNCH-2005) are presented. In the first case, airborne water vapor Differential Absorption Lidar (DIAL) data are used for an assimilation for 24 May 2002, where convection occurred along an eastward moving dryline in western Texas and Oklahoma south of a triple point that formed in western Oklahoma. In the second case, a network of three ground based water vapor Raman lidars, operated behind a sharp frontal rain band with a northwesterly flow, are used. The method employed, Four-Dimensional Variational Data Assimilation (4D-Var), is described in relation to other methods and the implementation is given in detail. The data assimilation results in a large modification of the initial fields. The assimilation into the preconvective conditions changed not only the water vapor field but also the location of convergence lines, causing positive modification of Convective Initiation (CI). In the LAUNCH-2005 case a strong correction of the vertical structure and the absolute values of the initial water-vapor field of the order of 1g/kg was found. This occurred mainly upstream of the lidar systems within an area that was comparable with the domain covered by the lidar systems. The correction of the water-vapor field was validated using independent Global Positioning System (GPS) sensors. Much better agreement with GPS zenith wet path delay was achieved with the initial water-vapor field after 4D-Var. Furthermore, the impact of the assimilation and its temporal evolution was investigated with introduced measures. The results demonstrate the high value of accurate vertically resolved mesoscale water va, Diese Arbeit untersucht die Auswirkungen der Assimilation von Wasserdampf Light Detection and Ranging (Lidar)-Daten in mesoskalige numerische Wettervorhersagemodelle (NWP). Zwei Fallstudien aus den Feldkampagnen International H2O Project 2002 (IHOP_2002) und International Lindenberg Campaign for Assessment of Humidity- and Cloud-Profiling Systems and its Impact on High-Resolution Modelling 2005 (LAUNCH-2005) werden vorgestellt. Im ersten Fall wurden flugzeuggestützte Differential Absorption Lidar (DIAL)-Wasserdampf-Daten für eine Assimilation am 24. Mai 2002 genutzt. An diesem Tag trat Konvektion entlang einer sich ostwärts bewegenden Feuchtefront im Westen Texas und in Oklahoma, südlich eines Tripelpunkt, auf. Im zweiten Fall wurde ein Netzwerk von drei bodengestützten Wasserdampf-Raman-Lidar-Systemen benutzt, welches nach Durchzug eines Regenbandes entlang einer Front und bei nordwestlichem Wind betrieben wurde. Die verwendete Methode, Four-Dimensional Variational Data Assimilation (4D-Var), wird erläutert und mit anderen Datenassimilationsmethoden verglichen, wobei die hierfür notwendigen Implementationen detailliert beschrieben werden. Die Datenassimilation hat eine große Änderung der Anfangsbedingungen zur Folge. Die Assimilation in die prekonvektiven Bedingungen veränderte nicht nur die Verteilung des Wasserdampfes, sondern auch die Lage von Konvergenzlinien, was die Auslösung von Konvektion (CI) positiv modifizierte. Im LAUNCH-2005 Fall wurde eine starke Korrektur der vertikalen Struktur und der absoluten Menge des initialen Wasserdampfes in der Größenordnung von 1g/kg festgestellt. Dies trifft hauptsächlich auf Gebiete im Lee der Lidar-Systeme zu. Die Korrektur des Wasserdampffeldes wurde mit unabhängigen Global Positioning System (GPS)-Messungen validiert. Durch die 4D-Var wurde eine bessere Übereinstimmung des Wasserdampf-Anfangsfeldes mit GPS Zenit Wet Path Delay (ZWD) erreicht. Außerdem wurde die Auswirkung der Assimilation und die weitere zeitlicher Ver

Se presenta la comparación de las salidas del modelo MM5 con datos tomados in situ en la Isla del Coco, Costa Rica. Las observaciones fueron realizadas en tres expediciones hechas a la isla en octubre del 2007, abril del 2008 y marzo del 2009. Para ejecutar las simulaciones se utilizaron las salidas del modelo de tiempo atmósferico del National Center for Environmental Prediction (NCEP), que inició a las 00 UTC y se empleó la retroalimentación dinámica en ambas direcciones. Se configuraron cuatro dominios de 90, 30, 10 y 3,3 km (42 x 47, 76 x 85, 100 x 121, 73 x 73 puntos) con 35 niveles en la vertical y con pronósticos de hasta 48 horas, cada tres horas. Se encontró que con las configuraciones físicas elegidas se realiza una mejor representación de los periodos húmedos que de los periodos con mayor precipitación en dicha zona. Tales resultados se manifiestan en las predicciones de humedad relativa y precipitación, lo que confirma la relación entre estas dos variables en la zona. Sin embargo, no se encontró una adecuada simulación de los patrones de radiación de onda corta incidente. La temperatura ha mostrado valores acordes con otros experimentos, mientras que el viento presentó una mejor simulación en los niveles medios que en capa límite.

This work investigates the impact of assimilating water vapor Light Detection and Ranging (lidar) data into mesoscale Numerical Weather Prediction (NWP) models. Two cases from the field campaigns International H20 Project 2002 (IHOP_2002) and International Lindenberg Campaign for Assessment of Humidity- and Cloud-Profiling Systems and its Impact on High-Resolution Modelling 2005 (LAUNCH-2005) are presented. In the first case, airborne water vapor Differential Absorption Lidar (DIAL) data are used for an assimilation for 24 May 2002, where convection occurred along an eastward moving dryline in western Texas and Oklahoma south of a triple point that formed in western Oklahoma. In the second case, a network of three ground based water vapor Raman lidars, operated behind a sharp frontal rain band with a northwesterly flow, are used. The method employed, Four-Dimensional Variational Data Assimilation (4D-Var), is described in relation to other methods and the implementation is given in detail. The data assimilation results in a large modification of the initial fields. The assimilation into the preconvective conditions changed not only the water vapor field but also the location of convergence lines, causing positive modification of Convective Initiation (CI). In the LAUNCH-2005 case a strong correction of the vertical structure and the absolute values of the initial water-vapor field of the order of 1g/kg was found. This occurred mainly upstream of the lidar systems within an area that was comparable with the domain covered by the lidar systems. The correction of the water-vapor field was validated using independent Global Positioning System (GPS) sensors. Much better agreement with GPS zenith wet path delay was achieved with the initial water-vapor field after 4D-Var. Furthermore, the impact of the assimilation and its temporal evolution was investigated with introduced measures. The results demonstrate the high value of accurate vertically resolved mesoscale water va, Diese Arbeit untersucht die Auswirkungen der Assimilation von Wasserdampf Light Detection and Ranging (Lidar)-Daten in mesoskalige numerische Wettervorhersagemodelle (NWP). Zwei Fallstudien aus den Feldkampagnen International H2O Project 2002 (IHOP_2002) und International Lindenberg Campaign for Assessment of Humidity- and Cloud-Profiling Systems and its Impact on High-Resolution Modelling 2005 (LAUNCH-2005) werden vorgestellt. Im ersten Fall wurden flugzeuggestützte Differential Absorption Lidar (DIAL)-Wasserdampf-Daten für eine Assimilation am 24. Mai 2002 genutzt. An diesem Tag trat Konvektion entlang einer sich ostwärts bewegenden Feuchtefront im Westen Texas und in Oklahoma, südlich eines Tripelpunkt, auf. Im zweiten Fall wurde ein Netzwerk von drei bodengestützten Wasserdampf-Raman-Lidar-Systemen benutzt, welches nach Durchzug eines Regenbandes entlang einer Front und bei nordwestlichem Wind betrieben wurde. Die verwendete Methode, Four-Dimensional Variational Data Assimilation (4D-Var), wird erläutert und mit anderen Datenassimilationsmethoden verglichen, wobei die hierfür notwendigen Implementationen detailliert beschrieben werden. Die Datenassimilation hat eine große Änderung der Anfangsbedingungen zur Folge. Die Assimilation in die prekonvektiven Bedingungen veränderte nicht nur die Verteilung des Wasserdampfes, sondern auch die Lage von Konvergenzlinien, was die Auslösung von Konvektion (CI) positiv modifizierte. Im LAUNCH-2005 Fall wurde eine starke Korrektur der vertikalen Struktur und der absoluten Menge des initialen Wasserdampfes in der Größenordnung von 1g/kg festgestellt. Dies trifft hauptsächlich auf Gebiete im Lee der Lidar-Systeme zu. Die Korrektur des Wasserdampffeldes wurde mit unabhängigen Global Positioning System (GPS)-Messungen validiert. Durch die 4D-Var wurde eine bessere Übereinstimmung des Wasserdampf-Anfangsfeldes mit GPS Zenit Wet Path Delay (ZWD) erreicht. Außerdem wurde die Auswirkung der Assimilation und die weitere zeitlicher Ver

An atmosphere, ocean waves, and ocean current coupled model system is extended to include the atmosphere land surface interactions and to connect the water heat and material circulation between the ocean and terrestrial circulation systems. The models used in this system are the non-hydrostatic atmospheric model (MM5), multi-layer land surface model (SOLVEG2), hydrological simulation program FORTRAN (HSPF), the third-generation ocean wave model of NOAA (WAVE WATCH III), and the Princeton Ocean Model (POM). The modeling system is divided into two main wings; the atmosphere-ocean wing, and the atmosphere-land surface wing. Both wings are combined to give a coupled atmosphere, land surface, hydrology, ocean wave, and ocean current model (ALHOM) that is capable to simulate the hydrological cycle on a regional scale. The coupled modeling system is a main part of currently running research project Asia Environmental Simulator (AES). Within AES the coupled modeling system will be applied for simulating water circulation and CO2 budgets in Kapuas river basin in Kalimantan Island, Indonesia, and for water circulation and water quality in Haji dam watershed in Hiroshima prefecture, Japan.

This study evaluates the data assimilation capabilities of Three Dimensional Multiquadric Interpolation (3DMQ) and the MM5 model when incorporating mesoscale observations from the United States Air Force Academy (USAFA) High Wind Alert system (HWAS). These mesoscale observations are incorporated into a triple nested (12, 4, and 1.33 km) high resolution model simulation and evaluated for their impact upon analyzed and forecasted wind values at USAFA during a severe down slope wind event that occurred on 6 March 2004. This evaluation is the first step in developing future forecasting and analysis tools for use by the military in various operations in complex terrain. The development of deployable automated tactical weather sensors in forward deployed locations requires an evaluation of the impact and usefulness these sensors would have on analysis forecast tools and mesoscale Numerical Weather Prediction (NWP) models. The juxtaposition of the HWAS network in complex terrain and the aviation training operations at USAFA provides an ideal set of data, mission and location for testing and evaluating a high resolution nested grid mesoscale NWP model. This study shows that incorporating HWAS observations into the 3DMQ data assimilation process has a significant impact upon verification of analyzed wind fields with the biggest impact occurring at the 1.33 km grid scale. Using these analyzed fields as initial conditions for MM5 model simulations, this study shows the ability of the 1.33 km model forecast wind fields to verify significantly better than either the 4 or 12 km through 18, 24, and 30 hour forecasts. Additionally, this study shows the limited, yet discernable impact HWAS observations have upon forecasted winds in the first several hours of MM5 model runs during a severe down slope wind event at USAFA.

Surface water and energy fluxes are tightly coupled with CO2 exchanges between the ecosystem and atmosphere. Other surface-to-atmosphere trace-gas exchanges of interest in climate change research (e.g., N2O, CH4, C18OO, and H218O) are also strongly impacted by surface energy exchanges. Further, land-use change has large effects on the surface energy balance and therefore the exchanges of these trace gases. To investigate these issues at the regional scale we have coupled MM5 (Grell et al. 1995) with ISOLSM (Riley et al. 2002, Riley et al. 2003), a land-surface model based on LSM1 (Bonan 1995).

Surface water and energy fluxes are tightly coupled with CO2 exchanges between the ecosystem and atmosphere. Other surface-to-atmosphere trace-gas exchanges of interest in climate change research (e.g., N2O, CH4, C18OO, and H218O) are also strongly impacted by surface energy exchanges. Further, land-use change has large effects on the surface energy balance and therefore the exchanges of these trace gases. To investigate these issues at the regional scale we have coupled MM5 (Grell et al. 1995) with ISOLSM (Riley et al. 2002, Riley et al. 2003), a land-surface model based on LSM1 (Bonan 1995).