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Simultaneous occurrence of metocean variables can present a multihazard to maritime systems. However, simplified design approaches to assess simultaneous significant wave heights and wind velocities are lacking, especially if seasonality is considered. This is addressed in this study by using extreme significant wave heights and companion wind velocities recorded in the Gulf of Mexico. Time-dependent, generalized extreme value (GEV) models and classical regression are the basis to propose a simplified approach to estimate correlated extreme significant wave heights and wind velocities associated with given return periods, accounting for seasonality and including measures of uncertainty. It is found that the proposed approach is a new but simple method to adequately characterize the concurrent extreme metocean variables and their uncertainty. It is concluded that the method is an effective probabilistic design tool to determine simultaneous extreme significant wave heights and companion wind velocities for desired return periods and seasonality. The financial support from the Erasmus Mundus Coastal and Marine Engineering and Management (CoMEM) programme and support from Laboratori d’Enginyeria Marítima, Universitat Politècnica de Catalunya and from Universidad de Guanajuato (CIIC 2020 Research Projects) is gratefully acknowledged. Acknowledgments: We thank two anonymous reviewers for their comments, suggestions and constructive criticism. We also thank guess Editor Guido Ventura and the editorial team of Applied Sciences for their help in the editorial process.

Tesis completa en lengua castellana y resumen en francés., [ES] El ecosistema pelágico en las regiones de aforamiento está sujeto a variabilidades espaciotemporales a distintas escalas, las que incluyen en todos los niveles de la cadena trófica. Sin embargo, recientemente se ha demostrado que las características físicas de mesoescala juegan un papel importantes en los ciclos de vida y la distribución de las poblaciones planctónicas y de peces pelágicos. La mesoescala se extiende de algunas decenas a cientos de kilómetros y de algunos días hasta varias semanas., [EN] The pelagic ecosystem in the regions of gauging is subject to spatial variability at different scales, which include all levels of the food chain. However, recently it has been demonstrated that the physical characteristics of mesoscale play important role in the life cycle and population distribution of planktonic and pelagic fish. The mesoscale ranges from several tens to hundreds of miles and several days to several weeks.

Màster Oficial en Meteorologia, curs 2006-2007, El routing meteorològic és una tècnica que consisteix en analitzar les condicions de vent presents i pronosticar les futures, per tal de traçar rutes òptimes per a vaixells de vela. Quan un vaixell fa una regata /offshore/, un dels factors decisius per guanyar és l'elecció de la ruta a seguir. Sovint el millor camí no és el més curt, i un vaixell lent pot guanyar la regata si troba la millor ruta. L'objectiu d'aquest treball és fer una anàlisi de les diferents tècniques de /routing/ per a vaixells de vela existents, així com desenvolupar noves metodologies. En una primera part es fa una aproximació més aviat teòrica als mètodes de /routing/ i, en la segona, es presenten les simulacions dutes a terme amb una eina de /routing/ desenvolupada per l'autor en un projecte cofinançat per la Fundació per la Navegació Oceànica de Barcelona, la Universitat de Barcelona i l'empresa Meteosim S.L., amb seu al Parc Científic de Barcelona., The meteorological routing is a technique that consists in analyzing the present and forecasting the future wind conditions in order to find optimal routes for sailing boats. In a sailing offshore race, one of the key factors to win is to choose a convenient track. As the shortest path is not always the faster, a slow boat can win the race if it finds the best track. The goal of this work is to overview the different routing schemes that are currently in use and to develop new methodologies. In a first section, a theoretical explanation is provided of the existing and proposed routing methods. In the second section, the practical application of a routing tool developed by the author is presented., Patrocinat: Meteosim S.L., Fundació per la Navegació Oceànica de Barcelona

This thesis explores the feasibility of making wind speed profile measurements from an oceanographic buoy using a Doppler sodar. In the fall of 2005, we deployed a Scintec SFAS sodar on an ASIS buoy. Roughly one week of buoy motion data and one day of sodar observations were collected. Data from both this deployment, and the Martha's Vineyard Coastal Observatory, were used in conjunction with models to predict sodar performance. Results are compared for an ASIS and a 3-meter discus buoy. We also predict the yearly average probability of sodar data availability in the presence of buoy motion. We show that buoy tilting in response to wave forcing is the main factor affecting sodar performance. Our results strongly suggest that ASIS is a suitable platform for sodar measurements at sea. http://archive.org/details/thefeasibilityof109452337 US Navy (USN) author. Approved for public release; distribution is unlimited.

This thesis study focuses on understanding the dissipation processes of the stratocumulus deck after sunrise. This objective is met through careful analyses of observational data as well as model simulations. Measurements from the Marine Atmosphere Measurement Lab (MAML) of the Naval Postgraduate School (NPS) are used in this study. In particular, the half-hourly wind profiler/Radio Acoustic Sounding System (RASS) measurements were used to determine the boundary layer top and the evolution of the boundary layer mean thermodynamic properties during the cloud breakup period. Measurements from a laser ceilometer and the routine surface measurements are also used to detect the variation of cloud base height, the evolution of the cloud deck, and the onset of sea breeze. These measurements revealed the increase of the boundary layer depth after sunrise followed by a decrease of the boundary layer depth after the onset of the sea breeze, which points to the role of surface heating and sea breeze development in modulating cloud evolution. The effects of surface heating and sea breeze are further tested using a 1-dimensional mixed layer model modified for coastal land surfaces. http://archive.org/details/evolutionofbound109452217 Lieutenant Commander, United States Navy Approved for public release; distribution is unlimited.

An analysis of in-situ aircraft observations collected in the parent cloud of a waterspout is presented. Previous waterspout studies were confined mainly to photometric and model simulated data, no in-situ observations were made internal to the parent cloud. On 27 June 2002 the Cooperative Institute for Remotely Piloted Aircraft Studies (CIRPAS) UV-18A Twin Otter aircraft collected observations in a cloud that had developed in a cloud line, located approximately 15km south of Key West, and that formed a waterspout. This study attempts to analyze the waterspout formation process using these data and through a series of scale interactions, from the synoptic scale down to the individual cloud scale. Based upon the analyzed data a hypothetical formation process is developed. The background synoptic scale flow is shown to establish the necessary ambient shear as a key factor in the waterspout formation. The orientation of mesoscale convergent boundaries and thermodynamic processes, internal to the cloud, proved to be an essential factor in developing the vertical motion patterns necessary for formation of an organized circulation in the shear region and to provide the tipping and stretching of the resultant vortex necessary to account for the waterspout formation. This is consistent with conclusions derived from previous studies. http://archive.org/details/acasestudyofinsi109452320 Captain, United States Air Force Approved for public release; distribution is unlimited.

This thesis is a study of the air-sea fluxes of momentum, sensible heat and latent heat. Fluxes are estimated using the covariance, COARE2.6b bulk flux algorithm, and inertial dissipation methods. The bulk algorithm is validated against the covariance fluxes for the first time in a light-wind, shallow tropical sea, with strong atmospheric instability and low sea state conditions. The removal of ship motion contamination is investigated. This is the first study to quantify the errors associated with corrections for ship motion contamination, and the effects of motion contamination on the covariance calculated heat fluxes. Flow distortion is investigated. Bulk transfer coefficients and roughness lengths are computed and related to the sea state. Ship motion contamination is successfully removed in 86% of the runs. Error analysis of the motion removal algorithm indicates maximum uncertainties of 15% in the wind fluctuations, and 0.002 N/m/m for the wind stress. Motion correction changes the stress by more than 15% in half of the runs analysed. The ship is found to accelerate the mean air flow and deflect it above the horizontal. A correction is developed for the air flow acceleration. The scalar fluxes show good agreement on average for all the methods. As wind speed approaches zero, covariance wind stress is significantly larger than the bulk and inertial dissipation derived wind stress. The non-zero covariance wind stress is reflected in the drag coefficient, CdN10, and momentum roughness length, z0, which are much larger than the parameterisations used in the bulk algorithm. The MCTEX CdN10, wind speed (u10N) relation is 1000 x Cd10N = 1.03 + 7.88/(u10N)^2 0.8 &lt u10N &lt 7.5 m/s z0 is primarily a function of wind speed rather than sea state, with largest roughness lengths occurring as wind speed approaches zero. This relation is used in the bulk algorithm, yielding good agreement between covariance and bulk derived wind stress. A new parameterisation for the effects of gustiness, based on wind variance is developed. This brings the bulk wind stress into agreement with the covariance derived wind stress.

Fifth International Aerosol Conference; 14-18 Sep. 1998; Edinburgh, Scotland; United Kingdom Aerosol effects on atmospheric radiative fluxes provide a forcing function that is a major source of uncertainty in understanding the past climate and predicting climate change. To help reduce this uncertainty, the 1996 Tropospheric Aerosol Radiative Forcing Experiment (TARFOX) and the 1997 second Aerosol Characterization Experiment (ACE-2) measured the properties and radiative effects of American, European, and African aerosols over the Atlantic. In TARFOX, radiative fluxes and microphysics of the American aerosol were measured from the UK C-130 while optical depth spectra, aerosol composition, and other properties were measured by the University of Washington C-131A and the CIRPAS Pelican. Closure studies show that the measured flux changes agree with those derived from the aerosol measurements using several modelling approaches. The best-fit midvisible single-scatter albedos (approx. 0.89 to 0.93) obtained from the TARFOX flux comparisons are in accord with values derived by independent techniques. In ACE-2 we measured optical depth and extinction spectra for both European urban-marine aerosols and free-tropospheric African dust aerosols, using sunphotometers on the R/V Vodyanitskiy and the Pelican. Preliminary values for the radiative flux sensitivities (Delta Flux / Delta Optical depth) computed for ACE-2 aerosols (boundary layer and African dust) over ocean are similar to those found in TARFOX. Combining a satellite-derived optical depth climatology with the aerosol optical model validated for flux sensitivities in TARFOX provides first-cut estimates of aerosol-induced flux changes over the Atlantic Ocean. RTOP 622-44-10-10 Approved for public release; distribution is unlimited.

The effects of aerosols on the microphysical characteristics of marine stratocumulus clouds can have a significant impact on climate processes through modification of cloud radiative properties. The effect of aerosols on clouds and the impact on climate processes have recently been discussed by several authors (Twomey et al., 1984; Coakley et al., 1987; Charlson et al., 1987). Of particular concern is the potential for observing variations of cloud characteristics that might be related to variations of available aerosols. The results of comparisons between aircraft-measured microphysical characteristics and satellite-detected radiative properties of marine stratocumulus clouds are presented. These results are extracted from Mineart (1988) and Durkee and Mineart (1989) where the analysis procedures and a full discussion of the observations are presented. Due to the space available, only a brief description of the results is presented. The satellite data used here are from the National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) collected at the Scripps Satellite Oceanography Facility. The AVHRR channel 1 (0.63 microns), channel 2 (0.86 microns), channel 3 (3.7 microns), and channel 4 (11 microns) data were used in the analysis. Cloud microphysical data were obtained by instruments on the NCAR Electra during cloud-penetrating missions in support of the field operations from 29 June to 19 July 1988. Approved for public release; distribution is unlimited.

The First ISCCP Regional Experiment (FIRE) objective of validating and improving satellite algorithms for inferring cloud properties from satellite radiances was one of the central motivating factors in the design of the specific field experimental strategies used in the July, 1987 marine stratocumulus intensive field observations (IFO). The in situ measuring platforms were deployed to take maximum advantage of redundant measurements (for intercomparison of the in situ sensors) and to provide optimal coverage within satellite images. One of the most ambitious of these strategies was the attempt to coordinate measurements from San Nicolas Island (SNI), the R/V Pt. Sur, the meteorological aircraft, and the satellites. For the most part, this attempt was frustrated by flight restrictions in the vicinity of SNI. The exception was the mission of July 16, 1987, which achieved remarkable success in the coordination of the platforms. This presentation concerns operations conducted by the National Center for Atmospheric Research (NCAR) Electra and how data from the Electra can be integrated with and compared to data from the Pt. Sur, SNI, and the satellites. The focus is on the large-scale, integrated picture of the conditions on July 16 from the perspective of the Electra's flight operations. Approved for public release; distribution is unlimited.

The article of record as published may be found at http://dx.doi.org/10.1175/1520-0493(1988)1162.0.CO;2 Two rapidly developing extratropical maritime cyclones (one, developed during January 13-15, 1979, along an intense frontal zone south of Japan, the other, of January 26-27, 1979, in a polar mass over the North Atlantic) were investigated using the FGGE data and ECMWF level IIIb analyses to describe the structure and dynamics of these events. Although the cyclones evolved from a strong low-level baroclinic zone without initial large midtropospheric vorticity advection, thus resembling the Petterssen type A development, rapid deepening occurred in both cases when an approaching upper tropospheric jet with appreciable shear vorticity advection became favorably superposed over the surface low. During the development period, stability decreased in the low troposphere, aiding in the rapid development of an intense mass-circulation and low tropospheric vorticity production by the divergence term. The results suggest that upper-level forcing plays a greater role in the initiation of explosive oceanic development than is suggested by the Petterssen and Smebye (1971) description. Approved for public release; distribution is unlimited.

Conocer el comportamiento de los diversos fenómenos meteorológicos es de gran importancia en el mundo marítimo, dado que ambos sectores están estrechamente relacionados. El presente Trabajo de Fin de Grado en Náutica y Transporte Marítimo se centra en el estudio de “la rissaga”, fenómeno que afecta principalmente en el Puerto de Ciudadela de Menorca. La peculiaridad principal de la rissaga es la fluctuación repentina del nivel del mar que produce dentro del puerto, consecuentemente todas las embarcaciones amarradas son gravemente dañadas. El gran destrozo inesperado que provoca, de difícil predicción, me despertó la curiosidad de saber más sobre el singular fenómeno. Ya que, además, destaca por su gran impacto en Ciudadela y no en bahías vecinas. A lo largo del trabajo, se analizan los factores meteorológicos y geográficos que favorecen su formación, así como la frecuencia en que sucede y los sistemas de predicción activos. Finalmente se exponen los efectos directos e indirectos que causa en el puerto deportivo/comercial, teniendo en cuenta su funcionamiento y rendimiento.

Els fenòmens meteorològics extrems, com les tempestes, generen afectacions socioeconòmiques addicionals en les zones costaneres, ja que en elles s’hi desenvolupen diverses activitats d’oci i de gran impacte econòmic. No obstant, les resolucions dels productes generats pels models globals (de l’ordre d’uns 50x50 km) són massa baixes per a usos en zones costaneres, degut a la major variabilitat orogràfica d’aquestes, provocant prediccions esbiaixades o imprecises dels models d’onatge o dels models oceànics. Per tal d’adaptar-se a aquesta complexitat és necessari anidar-se en els models globals per a augmentar la resolució dels dominis i les dades que generen. La irregularitat de la costa catalana permet estudiar els efectes d’assolir molt altes resolucions, d’1x1 km, en un període de tempesta. Amb la col·laboració del Barcelona Supercomputing Center – Centro Nacional de Supercomputación (BSC-CNS), en aquest estudi s’ha començat realitzant un anidament utilitzant el model meteorològic WRF-ARW, conjuntament a un anàlisi de sensibilitat d’aquest enfront la parametrització de la turbulència (considerant la formulació de Yonsei University, YSU, i la formulació de Mellor-Yamada-Janjic, MYJ) i les dades globals que forcen el model meteorològic (FNL, GFS, ERAInterim i EFIX). Les variables considerades en aquest bloc del treball són la velocitat i direcció mitjanes del vent a 10 m d’altura. Amb aquestes dades i la col·laboració del Laboratorio de Ingeniería Marítima (LIM) de la Universitat Politècnica de Catalunya (UPC), s’ha realitzat un anidament i un anàlisi de sensibilitat del model de generació i propagació de l’onatge SWAN enfront a combinacions de diferents resolucions dels dominis i inputs del model. Les variables considerades en el bloc d’onatge són l’altura d’ona significant, el període de pic i la direcció mitjana de l’onatge. D’aquests resultats es conclou que assolir molt altes resolucions (tant camps de vent com dels dominis del model d’onatge) no genera tants beneficis com en anteriors anidaments (de resolucions de fins a 3x3 km), a excepció de les direccions. També s’ha observat que el millor camp de vents no té perquè generar el millor camp d’onatge. Los fenómenos meteorológicos extremos, como las tormentas, generan afectaciones socioeconómicas importantes en las zonas costeras, ya que en ellas se desarrollan diversas actividades de ocio y de gran impacto económico. No obstante, las resoluciones de los productos generados por los modelos globales (del orden de 50x50 km) son demasiado bajas para su uso en zonas costeras, debido a la gran variabilidad orográfica de estas, provocando predicciones sesgadas o imprecisas de los modelos de oleaje o de los modelos oceánicos. Para poder adaptarse a esta complejidad es necesario anidarse en los modelos globales para aumentar la resolución de los dominios y de los datos que generan. La irregularidad de la costa catalana permite estudiar los efectos de llegar hasta muy altas resoluciones, de 1x1 km, en un periodo de tormenta. Con la colaboración del Barcelona Supercomputing Center – Centro Nacional de Supercomputación (BSC-CNS), en este estudio realizando un anidamiento del modelo meteorológico WRF-ARW, junto un análisis de sensibilidad de este enfrente la parametrización de la turbulencia (considerando la formulación de Yonsei University, YSU, y la formulación de Mellor-Yamada-Janjic, MYJ) y de los datos globales que fuerzan el modelo meteorológico (FNL, GFS, ERA-Interim y EFIX). Las variables consideradas en este bloque son la velocidad y dirección medias del viento a 10 m de altura. Con estos datos y con la colaboración del Laboratorio de Ingeniería Marítima (LIM) de la Universitat Politècnica de Catalunya (UPC), se ha realizado un anidamiento y un análisis de sensibilidad del modelo de generación y propagación del oleaje SWAN enfrente a combinaciones de diferentes resoluciones de los dominios y inputs del modelo. Las variables consideradas en este bloque son la altura significante, el período de pico y la dirección media del oleaje. De estos resultados se concluye que alcanzar muy altas resoluciones (tanto de los campos de viento como de los campos de oleaje) no genera tantos beneficios como en anteriores anidamientos (de resoluciones del orden de 3x3 km), a excepción de las direcciones. También se ha observado que el mejor campo de vientos no tiene porqué generar el mejor campo de oleaje. Extreme meteorological phenomena (p.e. storms) generate additional socioeconomic effects in coastal areas, where are developed many leisure activities or activities with huge economic impacts. However, the resolutions (around 50x50 km) of the products generated by global models are too small for using them in coastal areas, due to their orographic variability, driving into biased or inaccurate predictions of wave models or oceanic models. Then, there is a need to nest into this global models to increase the resolution of the domains and the data they produce to adapt better this complexity of the coastal areas. The irregularity of the catalan coast permits to study the effects of reaching very high resolutions, of 1x1 km, during a storm period. In collaboration with the Barcelona Supercomputing Center – Centro Nacional de Supercomputación (BSC-CNS), the present work proceed to do a nesting using the meteorological model WRF-ARW, together with a sensibility analysis of it in front the parametrization of turbulence (considering the formulation of Yonsei University, YSU, and the formulation of Mellor-Yamada-Janjic, MYJ) and the data from global models (FNL, GFS, ERA-Interim and EFIX) which feed the meteorological model. The variables considered in this block are the mean wind speed and the mean direction of the wind, both at 10 m high. Using these results and in collaboration with the Laboratorio de Ingeniería Marítima (LIM) of the Universitat Politècnica de Catalunya (UPC), it has been done a nesting and a sensibility analysis of the wave generation and propagation model SWAN in front combinations of different resolutions of the domains and the inputs of the model. The variables considered in this block are the significant wave height, the peak period and the mean wave direction. From those results it is possible to conclude that reaching very high resolutions (either of the wind fields or the wave fields) does not generate as much benefits as in previous nestings (of resolutions of 3x3 km), except in the case of wind and wave directions. Additionally, it has also been observed that the best wind field doesn’t have to generate the best wave field.

La meteorología del mar Mediterráneo siempre ha destacado por su imprevisibilidad, su bravura durante episodios meteorológicos extremos y por tener cambios radicales en las condiciones atmosféricas en periodos muy cortos de tiempo. Además de sus conocidos contrastes también posee unos regímenes de vientos bastante característicos en función de la zona y la época del año. Son bien conocidos en el norte de Cataluña los episodios de tramontana, los levantes en el Estrecho de Gibraltar o el mistral en el Golfo de León y en la zona del Delta del Ebro. Se puede llegar a pensar que estos vientos son fruto del azar, pero realmente el viento del Mediterráneo se rige por unas leyes muy concretas que si son conocidas permiten llegar a prever lo que va a pasar. El objetivo de este trabajo consiste en entender cuáles son estas leyes fundamentales que gobiernan la dinámica del Mediterráneo a través del conocimiento de sus particularidades geográficas, atmosféricas y locales, con el fin de entender cuáles son los vientos reinantes que se establecen en determinadas zonas de la cuenca durante el transcurso de las estaciones y las consecuencias que acarrean.

El Trabajo de Fin de Carrera, a continuación, versará explícitamente sobre el análisis de los complejos convectivos de mesoescala. Es realmente importante caracterizar lo mejor posible a estos sistemas, tanto por la torrencialidad de las precipitaciones y de las inundaciones catastróficas que provocan, como por su presencia en el litoral catalán.

Improving the knowledge of the ocean and seas surrounding the Iberian Peninsula and Balearic and Canary islands is an objective of the Spanish oceanography. For that purpose, a number of fixed and drifting floats have been established in the last 25 years. Data buoys measure sea surface temperature and salinity, ocean current velocity, air temperature, humidity, wave characteristic and wind velocity across seas and ocean. The objective is increase the quantity, quality, coverage and timeliness of atmospheric and oceanographic data. These observations are used immediately to improve forecast and therefore increase marine safety. The main group of fixed buoys is formed by the Puertos del Estado deep and shallow buoy networks, but a series of well instrumented new platforms has been established in later times. The RAIA Project (Xunta de Galicia), PLOCAN, SOCIB, IEO, Euskalmet-AZTI, ICM and UTM (CSIC) and University and Polytechnic of Barcelona have completed the Observing System. Most of the buoys are transmitting data by GTS for using in atmospheric and ocean prediction models. Multidisciplinary sensors as Dissolved Oxygen, Fluorescence Chlorophyll or pCO2 has been mounted in the buoys and calibration/validation procedures has been developed for improve data quality. Antifouling systems recently developed have also been included and quality of the optical sensors measurements has improved. Drifting floats has increase its number and importance, from Argo floats to traditional deriving ones improving the Spanish contribution to IOC and WWO and JCOMM. Spain is member of EuroArgo ERIC. SOCIB and IEO are the main contributors. Also multidisciplinary work has been done associated to Argo buoys. BGQ ARGO incorporate O2 sensor. ICM, SMOS Barcelona Expert Center, and SOCIB are the main contributors to the drifting buoys group. Main objectives are improving Technological development as well as data management. Tropical and Southern Atlantic Ocean are the main studying areas.

Sea storms are responsible for sudden and intense changes in coastal morphology. This dynamic behaviour can affect those towns and cities settled near the seashore, causing extensive material damage and loss of human life. The present thesis develops an assessment of episodic flooding and erosion at the coastal urban area of Riumar (Ebro Delta). Riumar is a tourist enclave placed in a low-lying territory, so that its future sustainability is, in addition, threatened by relative sea level rise. Conventional methods of analysis do not consider the interaction between beach morphology and storm waves nor the influence of coastal environment complexity, leading to a pseudo-realistic problem approach. In this thesis results derived from SWAN wave model have been used as forcing for XBeach, a 2DH model which couples hydrodynamic and morphodynamic processes. This methodology has been tested under current and future extreme wave climate and sea level conditions. Results show that acting at critical points can prevent episodic flooding in the medium term. However, coastal fragility imposes an upper-limit sea level beyond which coastal defence measures are no longer effective, urging the adoption of an action plan that pursues coastal assets’ realignment in the long term. Overall, this thesis shows the great potential of hydro-morphodynamic modelling as a tool to support urban and infrastructure planning in an increasingly changing and complex context. Els temporals de mar són responsables de canvis intensos i sobtats en la morfologia de la zona costanera. Aquest comportament dinàmic pot afectar les àrees urbanes properes a la vora del mar, causant greus danys materials i pèrdua de vides humanes. La present tesina desenvolupa una avaluació de la inundació i erosió episòdica a la urbanització costanera de Riumar (Delta del Ebre). Aquest enclavament turístic està situat a baixa cota, de manera que, a més, la seva sostenibilitat futura es veu amenaçada per l’augment relatiu del nivell del mar. Els mètodes d’anàlisi convencionals no consideren la interacció entre la morfologia de la platja i les condicions d’onatge ni tampoc la influència de la complexitat de l’entorn costaner, conduint a una aproximació del problema poc realista. En aquesta tesina els resultats obtinguts a través del model d’onatge SWAN s’han introduït a XBeach, un model 2DH que simula els processos hidrodinàmics i morfodinàmics de forma acoblada. Aquesta metodologia s’ha provat sota condicions actuals i futures de clima extrem d’onatge i nivell del mar. Malgrat que els resultats mostren que actuar en punts crítics pot evitar la inundació episòdica a mig termini, a partir d’un determinat nivell del mar les mesures de protecció costanera deixen de ser efectives. Això posa en evidència la fragilitat d’aquest entorn i insta a adoptar un pla d’acció que persegueixi la reordenació futura del litoral. En conjunt, aquesta tesina constata el gran potencial de la modelització hidro-morfodinàmica com a eina de suport al planejament urbanístic i de les infraestructures en un context cada vegada més canviant i complex. Los temporales de mar son responsables de cambios bruscos e intensos en la morfología de la zona costera. Este comportamiento dinámico puede afectar las zonas urbanas cercanas a la orilla del mar, causando graves daños materiales y pérdida de vidas humanas. La presente tesina desarrolla una evaluación de la inundación y erosión episódica en la urbanización costera de Riumar (Delta del Ebro). Este enclave turístico está situado a poca altura, de modo que su sostenibilidad futura se ve, además, amenazada por el aumento relativo del nivel del mar. Los métodos de análisis convencionales no consideran la interacción entre la morfología de la playa y las condiciones de oleaje ni tampoco la influencia de la complejidad del entorno costero, conduciendo a una aproximación del problema poco realista. En esta tesina los resultados obtenidos mediante el modelo de oleaje SWAN se han introducido en XBeach, un modelo 2DH que simula los procesos hidrodinámicos y morfodinámicos de forma acoplada. Esta metodología se ha probado bajo condiciones actuales y futuras de clima extremo de oleaje y nivel del mar. Aunque los resultados muestran que actuar en puntos críticos puede evitar la inundación episódica a medio plazo, a partir de un cierto nivel del mar las medidas de protección costera dejan de ser efectivas. Esto evidencia la fragilidad del entorno costero y empuja a adoptar un plan de acción que persiga la reordenación del litoral en el futuro. En conjunto, esta tesina constata el gran potencial de la modelización hidro-morfodinámica como herramienta de soporte al planeamiento urbanístico y de las infraestructuras en un contexto cada vez más cambiante y complejo.

este trabajo final de grado se ha centrado en realizar un estudio de los episodios climáticos en el estrecho de gibraltar y el mar mediterráneo. la metodología para realizar este trabajo ha sido primeramente capturar imágenes durante 90 días, una vez se obtuvieron las cartas de diferentes fuentes (agencia estatal de meteorologia (aemet), meteofrance, nacional oceanic and atmospheric administration (noaa) y windy) se ha procedido a realizar el análisis de las cartas del periodo seleccionado. finalmente, una vez se ha realizado el análisis se sacaron las conclusiones, pero para poder tener más detalles diarios, realizamos las conclusiones de cada quincena del mes y finalmente una conclusión mensual. el periodo seleccionado ha sido desde el 18 de marzo hasta el 30 de junio, dentro de este periodo comprende dos estaciones meteorológicas; la primavera y el verano. es por esto que podremos realizar una breve comparación meteorológica entre estas dos estaciones.

Since numerical weather prediction (NWP) models are usually used to force ocean circulation models, it is important to investigate their skill in reproducing surface meteorological parameters in open sea conditions. Near-surface meteorological data (air temperature, relative humidity, barometric pressure, wind speed and direction) have been acquired from several sensors deployed on an offshore large spar buoy in the Ligurian Sea (Northern Mediterranean Sea) from February to December 2000. The buoy collected 7857 valid records out of 8040 during 335 days at sea. These observations have been compared with data from NWP models and specifically, the outputs of the ECMWF analysis in the two grid points closest to the buoy position. Hourly data acquired by the buoy have been undersampled to fit the data set of the model composed by values computed at the four synoptic hours. For each mentioned meteorological parameter an analysis has been performed by evaluating instantaneous synoptic differences, distributions, daily and annual variations and related statistics. The comparison shows that the model reproduces correctly the baric field while significant differences result for the other variables, which are more affected by local conditions. This suggests that the observed discrepancies may be due to the poor resolution of the model that probably is not sufficient to appropriately discriminate between land and ocean surfaces in a small basin such as the Ligurian Sea and to take into account local peculiarities. The use of time- and space-averaged model data reduces the differences with respect to the in situ observations, thus making the model data usable for analysis with minor requirements about time and space resolution. Although this comparison is strongly limited and we cannot exclude measurement errors, its results suggest a great caution in the use of the model data, especially at high frequency resolution. They may lead to incorrect estimates of atmospheric forcing into ocean circulation models, causing important errors in those areas, such as the Mediterranean Sea, where ocean circulation is strongly coupled with atmosphere and its high variability. Key words. Oceanography; general (marginal and semiclosed seas; marine meteorology; numerical modelling)

La selecció de la ruta d'una embarcació, a partir de previsions meteo-oceanogràfiques, és un exercici d'optimització que permetria incrementar la seguretat i el confort durant el trajecte, reduir-ne la durada i el consum de combustible.Avui dia es disposen de prediccions meteo-oceanogràfiques força precises de qualsevol part de l'oceà. L'objectiu d'aquesta tesina és plantejar i programar l'algoritme de càlcul que, en funció de les característiques de l'embarcació, dels ports d'origen i destinació i de les previsions meteo-oceanogràfiques disponibles, determini la ruta òptima a seguir per a cada grau de seguretat i confort requerit, temps màxim de navegació i estalvi de combustiblle requerit.

L’objectiu d’aquest treball és estudiar i entendre com es forma una tempesta, les condicions que s’han de donar perquè es produeixi, i com es comporta i es desenvolupa. Es tractarà també l’impacte que tenen les tempestes en la societat i, més en concret, en els navegants, tant en petites embarcacions d’esbarjo com en grans vaixells mercants. S’estudiaran casos extrems i particulars que es donen especialment al litoral Mediterrani, com els MCC (Sistemes Convectius Mesoescalars, sigles en català SCM), les DANA (Depressió Aïllada en Nivells Alts, anomenada també gota freda) i els Medicanes (contracció o unió de “Medi”, de Mediterrani, i de “canes”, de hurricanes, huracans en anglès). Es realitzarà una part pràctica. Aquesta consistirà en l’estudi d’unes dades que es recolliran gràcies a l’AEMET (Agència Estatal de Meteorologia) d’una estació meteorològica situada a Balsareny, situat al nord de la comarca del Bages, durant 5 mesos (entre abril i setembre del 2018). Mitjançant taules i gràfiques, s’analitzaran en quines condicions de vent i temperatura s’han donat precipitacions i s’intentaran extreure conclusions per demostrar si estan relacionades entre elles o no.

Earth observation satellite programs are currently facing, for some applications, the need to deliver hourly revisit times, subkilometric spatial resolutions, and near-real-time data access times. These stringent requirements, combined with the consolidation of small-satellite platforms and novel distributed architecture approaches, are stressing the need to study the design of new, heterogeneous, and heavily networked satellite systems that can potentially replace or complement traditional space assets. In this context, this paper presents partial results from ONION, a research project devoted to studying distributed satellite systems and their architecting characteristics. A design-oriented framework that allows selecting optimal architectures for the given user needs is presented in this paper. The framework has been used in the study of a strategic use-case and its results are hereby presented. From an initial design space of 5586 potential architectures, the framework has been able to preselect 28 candidate designs by an exhaustive analysis of their performance and by quantifying their quality attributes. This very exploration of architectures and the characteristics of the solution space are presented in this paper along with the selected solution and the results of a detailed performance analysis.