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27 páginas, 15 figuras, 6 tablas.-- El documento se encuentra en su versión post-print. ; This paper analyses the spatial and temporal variability of winter droughts in a semi-arid geographic gradient in Northeast Spain, from the Pyrenees in the north to the Mediterranean coastland in the south. Droughts that occurred between 1952 and 1999 were analysed by means of the Standardised Precipitation Index (SPI). The influence of the weather-type frequency and of the general North Atlantic atmospheric circulation patterns was analysed. The results indicate that winter droughts show an important spatial variability in the study area, differentiating three well-defined patterns. These correspond to the Pyrenees, the centre of the Ebro Valley, and the Mediterranean coastland. General negative trends in winter SPI have been found, which are indicative of the increase in winter drought conditions in the study area. Nevertheless, important spatial differences have also been recorded. Dominant north–south gradients in the influence of weather types are shown. Moreover, the negative trends in winter-SPI values agree with the negative trend in the frequency of the weather types prone to cause precipitation, such as the C, SW and W weather types and the increase in the frequency of A weather types. Nevertheless, in the Mediterranean coastland, the positive trend in SPI values agrees with the increase in the frequency of weather types of the east (E, SE), which are prone to cause precipitation in this area. Interannual variations in the frequency of the different weather types have been highly determined by different general atmospheric circulation patterns, mainly the North Atlantic Oscillation (NAO). Nevertheless, the correlation between the time series of weather-type frequency and the winter SPI is higher than that found between the SPI and the NAO. Thus, although the interannual NAO variability explains a high percentage of the interannual differences in the frequency of different weather types, it is not sufficient to explain the spatial and temporal variability of droughts, which respond better to atmospheric variability at more detailed (synoptic) spatial scales. ; This work has been supported by the projects: 'Caracterización espacio-temporal de las sequías en el valle medio del Ebro e identificación de sus impactos' (BSO2002-02743), 'Variabilidad climática y dinámica forestal en ecosistemas de ecotono' (REN2003-07453), Procesos hidrológicos y erosivos en cuencas pirenaicas en relación a cambios de usos de suelo y variabilidad climática (PIRIHEROS, REN2003-08678/HID) 'Caracterización y modelización de procesos hidrológicos en cuencas aforadas para predicción en cuencas no aforadas' (CANOA, CGL 2004-04919-c02-01), all funded by the Spanish Commission of Science and Technology (CICYT) and FEDER, and 'Programa de grupos de investigación consolidados' (grupo Clima, Cambio Global y Sistemas Naturales, BOA 48 of 20-04-2005), financed by the Aragón Government. We want to thank to the National Institute of Meteorology (INM) for providing the data used in this work. Research of the second author was supported by postdoctoral fellowships by the Ministerio de Educación, Cultura y Deporte (Spain). ; Peer reviewed

The conclusion of this essay could be expressed as follows: Kant was a scientist at heart. His early lectures on geography and oceanography as well as his publications on geophysics, meteorology, astronomy, etc. set new standards in terms of their educational, social, political and scientific approach. During the 1750s they were completely abreast of current developments in professional research. With regard to geography, it is clear that Kant was struggling to find a systematic method. As the years progressed, he is likely to have realized that improving the system would not be easy. When assessing Kant and his scientific work, one must always bear in mind that he was possessed by a considerable urge to engage in scientific research, and that he set very high standards for himself. Until well into the 1760s, he could still certainly have become a physicist and geoscientist, and the fact that he ended up specializing in theoretical philosophy certainly has a great deal to do with his previous education. This would also explain why he does not employ mathematical means to solve problems in his scientific writings but rather tends to avoid them. The question as to whether Kant had an influence on today's natural sciences is a controversial one. Were his scientific documents of any significance? His work is indeed distinctive for its visionary approach, but whether this was of any help to the natural scientists in around 1800 is generally regarded as doubtful. The question as to whether Kantian philosophy had any influence on the natural sciences is usually answered in the affirmative, however: Kant is described as the leading authority of the Enlightenment. His influence on social and political developments is emphasized, and linked to progress made in the natural sciences. One fact is perplexing, however: Major research libraries have no books by, or about, Kant, quite clearly indicating that Kant's philosophical writings have never been read by natural scientists. Kant abandoned his lectures on mathematics and physics in the course of the 1770s, but continued with his geography lectures. The latter formed the basis for his 1772 lecture on anthropology. Kant imbued these lectures with a generally educational and Enlightenment-oriented character rather than a purely scientific one. From Kant's point of view, this limitation was very necessary: It relieved him from the "constraint" of having to undertake active research and publish his work in this sector. In 1798, having already retired as a professor, he published his much-read "Anthropology" (Kant, 1798). He seems to have struggled with a systematization of geography until well into the 1780s but been unable to reach a definitive decision. This circumstance was probably the main reason why no original Kantian "Geography" has come down to us. Kant's influence on oceanography as a part of geography is based on the fact that he was one of the first to recognize the importance of the subject, give lectures on it and captivate generations of students with his enthusiasm for it.

False Bay is the largest (circa 1000km²) natural, coastal embayment on the South African coastline and is located between latitudes 34°04'S and 34°23'S and longitudes 18°26'E and 18°52'E at the southern tip of Africa, near Cape Town, South Africa. The semi-enclosed nature of the bay makes it unsuitable as a 'sink' for all the contaminated urban stormwater run-off and the greatly increased pollution loads entering the bay. All pollution point sources entering False Bay were identified and described, and some of these selected for detailed study, the emphasis being on the impact of some individual discharges on the subtidal macrofauna. The similar biotic characteristics of three subtidal study sites in the region of the Steenbras Water Treatment Plant discharge indicate that the general turbidity and lower salinity characteristics of eastern False Bay are more likely to be responsible for the impoverished diversity near the outfall rather than the aluminium content of the discharge. Toxicity experiments on the bivalves Choromytilus meridionalis, Mytilus galloprovincialis and Perna perna using alum and ferric sludge indicate that there are no significant short-term sub-lethal toxic effects on the rocky shore bivalves and that decreased salinities in the immediate region of the outfall (as a result of the freshwater stream input) may have a more deleterious effect. A study of eighteen subtidal sites in False Bay indicated that overall densities of subtidal macro plastic debris were low, but that there are some 'hot spots' where densities are relatively high viz., Kalk Bay, Strandfontein, Mnandi, Monwabisi and Gordon's Bay. Colonising of debris by benthic organisms does occur, mostly on white plastic. Most of the debris consisted of plastic packaging from local land-based sources, indicating that it originates from wind-blown litter left by beachgoers. The highest density at the Sunnycove Control Site occurred in January during the peak holiday season. A longer term (three years) study of the subtidal environment in the vicinity of the Marine Oil Refiners outfall pipe indicated that the lack of subtidal macro fauna is more likely due to the harsh environmental conditions (abrasion and smothering) rather than the pollution impact of the outfall. This is confirmed by the abundant, healthy and diverse community on the nearby wreck of the Clan Stuart (1917) which indicates a stable ecosystem. The complexity of False Bay - its unique topography, bathymetry, meteorology make it difficult to attain a true climatic or average circulation. This lack of a consistent conceptual overview of the False Bay physical circulation is a short-coming that needs to be urgently addressed if the dangers of pollution inputs are to be accurately assessed. An overall management policy for False Bay should be urgently formulated and an officially constituted body with legislative power is needed if holistic management of the bay is to be achieved and such a prime recreational asset preserved for future generations. Bibliography: pages 195-225.

A clear, concise discussion of today's hottest topics in climate change, including adapting to climate change and geo-engineering to mitigate the effects of change, Engineering Response to Climate Change, Second Edition takes on the tough questions of what to do and offers real solutions to the practical problems caused by radical changes in the Earth's climate. From energy consumption and carbon dioxide emissions reduction, to climate-altering technologies, this new edition explores the latest concerns such as acidification of the ocean, energy efficiency, transportation, space solar power, and future and emerging possibilities. The editors set the stage by discussing the separate issues of the emissions of radiatively important atmospheric constituents, energy demand, energy supply, agriculture, water resources, coastal hazards, adaption strategies, and geo-engineering. They explain the difference between the natural and human drivers of climate change and describe how humans have influenced the global climate during past decades. Each chapter concludes with discussion questions, calculations, and possible research topics. See What's in the Second Edition: New conceptual tools and research necessary for problems associated with fossil fuels Cutting-edge topics such as adaption and geo-engineering The latest concerns such as acidification of the ocean, energy efficiency, transportation, and space solar power Solutions to problems caused by changes in the Earth's climate So much has changed in the 15 years since the publication of the first edition, that this is, in effect, a completely new book. However, the general theme is the same: the climate energy problem has become largely an engineering problem. With this in mind, the book explores what engineers can do to prevent, mitigate, or adapt to climate change.

This book, which contains 17 chapters, presents an expert synthesis of greenhouse gas (GHG) sink science and how this applies to the past, current and future changes in climate. It also explores how the sinks may respond to increased GHG emissions and global temperatures, and whether they can be protected and even enhanced to help mitigate climatic change. The sinks discussed in this book are the planet's storage areas, where GHGs are locked away from the atmosphere and thus prevented from contributing to global warming. This book is a valuable resource for students, researchers and practitioners in conservation, ecology and environmental studies.

WOS: 000427563600009 ; Science Citation Index Expanded ; The Paris Agreement of the United Nations Framework Convention on Climate Change aims not only at avoiding +2 degrees C warming (and even limit the temperature increase further to +1.5 degrees C), but also sets long-term goals to guide mitigation. Therefore, the best available science is required to inform policymakers on the importance of and the adaptation needs in a +1.5 degrees C warmer world. Seven research institutes from Europe and Turkey integrated their competencies to provide a cross-sectoral assessment of the potential impacts at a pan-European scale. The initial findings of this initiative are presented and key messages communicated. The approach is to select periods based on global warming thresholds rather than the more typical approach of selecting time periods (e.g., end of century). The results indicate that the world is likely to pass the +1.5 degrees C threshold in the coming decades. Cross-sectoral dimensions are taken into account to show the impacts of global warming that occur in parallel in more than one sector. Also, impacts differ across sectors and regions. Alongside the negative impacts for certain sectors and regions, some positive impacts are projected. Summer tourism in parts of Western Europe may be favored by climate change; electricity demand decreases outweigh increases over most of Europe and catchment yields in hydropower regions will increase. However, such positive findings should be interpreted carefully as we do not take into account exogenous factors that can and will influence Europe such as migration patterns, food production, and economic and political instability. ; European Union [282746]; Niels Stensen Fellowship; Veni-grant of NWO Earth and Life Sciences [863.14.008]; RCN [255397] ; We are grateful to use the data which were obtained during the course of work of the project IMPACT2C: Quantifying projected impacts under 2 degrees C warming. IMPACT2C has received funding from the European Union Seventh ...

International audience The calibration of the CloudSat spaceborne cloud radar has been thoroughly assessed using very accurate internal link budgets before launch, comparisons with predicted ocean surface backscatter at 94 GHz, direct comparisons with airborne cloud radars, and statistical comparisons with ground-based cloud radars at different locations of the world. It is believed that the calibration of CloudSat is accurate to within 0.5 to 1 dB. In the present paper it is shown that an approach similar to that used for the statistical comparisons with ground-based radars can now be adopted the other way around to calibrate other ground-based or airborne radars against CloudSat and/or detect anomalies in long time series of ground-based radar measurements, provided that the calibration of CloudSat is followed up closely (which is the case). The power of using CloudSat as a Global Radar Calibrator is demonstrated using the Atmospheric Radiation Measurement cloud radar data taken at Barrow, Alaska, the cloud radar data from the Cabauw site, The Netherlands, and airborne Doppler cloud radar measurements taken along the CloudSat track in the Arctic by the RASTA (Radar SysTem Airborne) cloud radar installed in the French ATR-42 aircraft for the first time. It is found that the Barrow radar data in 2008 are calibrated too high by 9.8 dB, while the Cabauw radar data in 2008 are calibrated too low by 8.0 dB. The calibration of the RASTA airborne cloud radar using direct comparisons with CloudSat agrees well with the expected gains and losses due to the change in configuration which required verification of the RASTA calibration.

Although air quality in the United States has improved remarkably in the past decades, ground-level ozone (O 3 ) often rises in exceedance of the national ambient air quality standard in nonattainment areas, including the Long Island Sound (LIS) and its surrounding areas. Accurate prediction of high-ozone episodes is needed to assist government agencies and the public in mitigating harmful effects of air pollution. In this study, we have developed a suite of potential forecast improvements, including dynamic boundary conditions, rapid emission refresh and chemical data assimilation, in a 3 km resolution Community Multiscale Air Quality (CMAQ) modeling system. The purpose is to evaluate and assess the effectiveness of these forecasting techniques, individually or in combination, in improving forecast guidance for two major air pollutants: surface O 3 and nitrogen dioxide (NO 2 ) . Experiments were conducted for a high-O 3 episode (28–29 August 2018) during the Long Island Sound Tropospheric Ozone Study (LISTOS) field campaign, which provides abundant observations for evaluating model performance. The results show that these forecast system updates are useful in enhancing the capability of this 3 km forecasting model with varying effectiveness for different pollutants. For O 3 prediction, the most significant improvement comes from the dynamic boundary conditions derived from the NOAA operational forecast system, National Air Quality Forecast Capability (NAQFC), which increases the correlation coefficient ( R ) from 0.81 to 0.93 and reduces the root mean square error (RMSE) from 14.97 to 8.22 ppbv, compared to that with the static boundary conditions (BCs). The NO 2 from all high-resolution simulations outperforms that from the operational 12 km NAQFC simulation, regardless of the BCs used, highlighting the importance of spatially resolved emission and meteorology inputs for the prediction of short-lived pollutants. The effectiveness of improved initial concentrations through optimal interpolation (OI) is shown to be high in urban areas with high emission density. The influence of OI adjustment, however, is maintained for a longer period in rural areas, where emissions and chemical transformation make a smaller contribution to the O 3 budget than that in high-emission areas. Following the assessment of individual updates, the forecasting system is configured with dynamic boundary conditions, optimal interpolation of initial concentrations and emission adjustment, to simulate a high-ozone episode during the 2018 LISTOS field campaign. The newly developed forecasting system significantly reduces the bias of surface NO 2 prediction. When compared with the NASA Langley GeoCAPE Airborne Simulator (GCAS) vertical column density (VCD), this system is able to reproduce the NO 2 VCD with a higher correlation (0.74), lower normalized mean bias (40 %) and normalized mean error (61 %) than NAQFC (0.57, 45 % and 76 %, respectively). The 3 km system captures magnitude and timing of surface O 3 peaks and valleys better. In comparison with lidar, O 3 profile variability of the vertical O 3 is captured better by the new system (correlation coefficient of 0.71) than by NAQFC (correlation coefficient of 0.54). Although the experiments are limited to one pollution episode over the Long Island Sound, this study demonstrates feasible approaches to improve the predictability of high-O 3 episodes in contemporary urban environments.

La aplicación del fuego prescrito en el sur de España está limitada debido en parte a la falta de conocimientos debidamente documentados, a la ausencia de normativas oficiales que respalden y regulen los procesos y a las características de la vegetación en estos ambientes mediterráneos continuidad vertical entre estratos y presencia de especies muy inflamables. Sin embargo, el uso del fuego prescrito sí podría ser una alternativa ó complemento a los trabajos mecánicos en el mantenimiento de las áreas cortafuegos arboladas. La puesta en marcha de un programa de quemas prescritas requiere estudios previos que analicen su viabilidad y aporten herramientas y procedimientos que faciliten su implementación. En este sentido, la presente tesis desarrolla procedimientos y analiza los resultados obtenidos de las quemas prescritas ejecutadas en la provincia de Málaga entre 1999 y 2000 en el marco del proyecto de "Gestión, capacitación, formación y experimentación de técnicas de control de la carga de combustibles mediante la aplicación de quemas prescritas" cofinanciado por la Dirección General VI de la Comisión Europea y la Junta de Andalucía. Los capítulos incluidos en la tesis persiguen: (1) definir un procedimiento para localizar las unidades de quemas prescritas mediante SIG; (2) desarrollar un método de estimación de la carga de combustible compatible con el uso del fuego prescrito; (3) analizar el grado de consumo del combustible superficial y su caracterización con variables descriptoras de la estructura del complejo vegetal, comportamiento del fuego observado, registros meteorológicos durante la quema, y efectos sobre el estrato arbóreo; y (4) valorar la eficacia de la quema con respecto al incremento de altura basal arbórea (efecto poda térmica), analizando sus implicaciones en los procesos de transición y cese de la actividad de copas. Los resultados facilitarán futuras aplicaciones de las quemas prescritas como herramienta preventiva de incendios forestales en ambientes mediterráneos. ; The use of broadcast burning as a fuel treatment is not used in Southern Spain nowadays due to lack of knowledge, absence of official regulations and characteristics of the vegetation in these Mediterranean areas, such as the existence of multiple strata or high flammability species. However, the use of prescribed fire could be an interesting alternative for the maintenance of shaded fuelbreak areas. With the aim of studying the viability of such fuel treatment, a project for the "management, training and experimentation of fuel load reduction by the use of prescribed burning", co-funded by the European Comission VI General Direccion and the Andalusia State Government, was developed between 1999 and 2000 at Malaga province. The present thesis develops procedures and analyzes the results obtained through the following chapters' main goals: (1) to define a GIS procedure to localize the prescribed burning units and plots; (2) to develop a fuel load estimation method compatible with prescribed fire management; (3) to analyze fuel load consumption, characterizing its relation through mathematical models with relevant to fuel complex, fire behavior and meteorology descriptors; and (4) to valorize the prescribed burns with relevant to the observed increment in crown base height due to thermal pruning, analyzing its implications on crown fire initiation and cessation. Results will ease the use of RX-fire as a fuel treatment in forest fire prevention in Southern Spain.

The Natural Sources of pollutants, such as Sahara desert dust outbreaks or ashes from vulcanoes, in many cases, could grow the bad air quality forecast and PM limits values measured could exeed the European Law recomendations, in that case the country have to pay to the Community if an evidence of that is a Natural Pollutant is not brought to the European Court. The goal to control air quality could be reached studying the pollution sources, the dispersion with atmospheric model, the chemical reactions occurring and also the study of air depositions. Exeedences of air quality limit value represent breaches of Community law which can have significant legal consequences for the European Member States. For some existing limit values, such as those in the directive 1999/30/EC (first daughter Directive), an exeedence which is caused by particular natural sources can be ignored for the purpose of ensuring compliance with Community law; article 2.15 of the first daughter directive defines "natural events" as volcanic eruptions, seismic activities, geothermal activities, wild-land fires, high wind events or the atmospheric resuspension or transport of natural particles from dry regions. The next air quality directive will likely extend this principle to natural (i.e. Non anthropogenic) sources of pollution generally so long as the "natural contribution" can be quantified and documented. Particle Matters (PM) emissions sources are sea-spray, soil moved by wind, biogenic aerosols, volcanic emissions, forest fires, and anthropogenic sources. The EU legislation give limits for mobile emission, there are many like the Euro X limitation for private cars (gasoline and diesel). To control the road transport emissions there is a common trend of modification of the engines technology, the reduction of traffic in big city centre, the use of Pb and S free fuel, the promotion of the use of renewable energy and the use of alternative fuel. A cure strategy is post combustion treatment. The aim of this PhD work is to present a new way to approach radiative tranfer on air when dust episodes occurs, and to start a study/work group able to inform, with quality and quantity data, on natural sources of air pollution, capable to discuss with other governative and regional organizations such as ARPAS (with monitoring in site stations or mobile devices), and POLARIS 's entrerprises, which main topic is dealing with Environmental Science and Air quality. It is globally achieved that dust is part of natural aerosols quantity in air, with dimension from 1 to 10 microns, and could affect both human health, for breath disease, and local climate system, or global as well. Dust could reach Mediterranean and South European countries because of the local meteorology, the source points are often in the Sahara desert. Using Satellites Spectroradiometry we could detect and visualise dust over land and oceans. We used three Modis combination bands into the multispectral data analysis toolkit HYDRA (HYperspectral data viewer for Development if Research Application): a simple algorithm is showed with the help of HYDRA software, that help scientists to see dust easly without any other processed data. A case study is showed over the South West Mediterranean Area, near Tunisia and Lybia, but could be used for any other case and area of the world.

An account of the mobilization of thousands of volunteers who rescued, supported, and welcomed refugees during the recent European refugee crisis.

This book provides insights on the topic of tourism destination management, focusing on the analysis of three main issues: (1) the factors influencing destination competitiveness, (2) the environmental dimension of tourism (including climate change issues); and (3) destination sustainability. The book is structured into three parts comprising 15 main chapters. Each part constitutes a monographic view on every topic analysed through the book. The chapters employ case studies in order to illustrate their contributions. The analysis presents an interdisciplinary approach, including contributions from economists, managers, geographers and marketing professionals.

What is air? Why is the sky blue? Why do people react favorably to mountain or sea air? How does desert air differ from the air of California's Central Valley? How is air pollution affecting plants and animals? This book is a unique guide to the air we breathe in California. More than a natural history guide, it approaches this fascinating topic by recognizing the overwhelming role played by humans in the story of California's air. In a highly engaging style, David Carle explains daily weather patterns, seasonal climate, characteristic winds, and sky phenomena. He explores air as the gases in our atmosphere, but also considers the aspects of air that influence all of our senses—its taste, smell, feel, and look. The guide discusses California's history of air quality management, air pollution and its effect on humans and the environment, and the technological and individual measures needed to address these challenges. The book also functions as a handbook for more environmentally conscious living by providing information on alternative energy sources for consumers and tips for cleaner running cars. * Features 80 color photographs, 23 figures, 18 maps* Covers regional differences of topography, weather, and the character of the air in California's fifteen designated air basins* Includes a field guide to the sky, explaining color and light, clouds and wind, and the nature of flight* Addresses issues surrounding global climate change in CaliforniaA book in the Californians and Their Environment subseries, dedicated to understanding human influences on the state's ecology and natural resources

Annotation ANALYTICAL METHODS AND PROCEDURES FOR ALL ASPECTS OF THE ENVIRONMENT - IN ONE HANDY REFERENCE! Here is the first book to bring together and fully explain the analytical methods and procedures used or every aspect of the environment - water, soil, and air. Designed to be the first point of reference for anyone wanting to monitor environmental variables, the "Handbook examines all the methods and problems associated with each monitoring method. Edited by an international team of four hands-on experts, "Environmental Monitoring Handbook covers all types of monitoring including: * Chemical * Biological * Hydrological * Ectotoxological * Microbiological * Physical You'll also find a thorough discussion of data analysis and experimental design as they pertain to environmental monitoring. If you're looking for a single definitive source of environmental monitoring information, your search ends here. Annotation.

Global climate models (GCMs) are known to suffer from biases in the simulation of atmospheric blocking, and this study provides an assessment of how blocking is represented by the latest generation of GCMs. It is evaluated (i) how historical CMIP6 (Climate Model Intercomparison Project Phase 6) simulations perform compared to CMIP5 simulations and (ii) how horizontal model resolution affects the simulation of blocking in the CMIP6-HighResMIP (PRIMAVERA – PRocess-based climate sIMulation: AdVances in high-resolution modelling and European climate Risk Assessment) model ensemble, which is designed to address this type of question. Two blocking indices are used to evaluate the simulated mean blocking frequency and blocking persistence for the Euro-Atlantic and Pacific regions in winter and summer against the corresponding estimates from atmospheric reanalysis data. There is robust evidence that CMIP6 models simulate blocking frequency and persistence better than CMIP5 models in the Atlantic and Pacific and during winter and summer. This improvement is sizeable so that, for example, winter blocking frequency in the median CMIP5 model in a large Euro-Atlantic domain is underestimated by 33 % using the absolute geopotential height (AGP) blocking index, whereas the same number is 18 % for the median CMIP6 model. As for the sensitivity of simulated blocking to resolution, it is found that the resolution increase, from typically 100 to 20 km grid spacing, in most of the PRIMAVERA models, which are not re-tuned at the higher resolutions, benefits the mean blocking frequency in the Atlantic in winter and summer and in the Pacific in summer. Simulated blocking persistence, however, is not seen to improve with resolution. Our results are consistent with previous studies suggesting that resolution is one of a number of interacting factors necessary for an adequate simulation of blocking in GCMs. The improvements reported in this study hold promise for further reductions in blocking biases as model development continues. ; This research has been supported by the European Commission (PRIMAVERA (grant no. 641727)), the Spanish government (PALEOSTRAT (grant no. CGL2015-69699-R) and JEDiS (grant no. RTI2018-096402-B-I00)), and the Ministry of Science and Higher Education of Russia (grant no. 0149-2019-0015). ; Peer Reviewed ; Postprint (published version)