942 resultados para East Coast fever
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Understanding the Eastern Coyote - Part II, by Thomas N. Tomsa, Jr., USDA-APHIS-ADC, Pennsylvania Book Review - "The Dirt Hole and Its Variations" All Texas Counties Quarantined for Rabies Ravenous Vultures Decimating Sheep & Calves on the East Coast Four-Year-Old Dies of Rabies The National Urban Wildlife Management Association (NUWMA) officially merged with NADCA, to create one larger, more effective organization to work for professional Animal Damage Control. State-Endangered Species: Meaningful Management or Preservationist Politics?, by Richard B. Chipman, Wildlife Biologist, USDA-APHIS-ADC, Vermont NADCA Membership Meeting Trapping Weasels
Jack H. Berryman 1995 Leopold Award Winner
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This paper presents a comprehensive review on the interaction between hydrodynamic processes, beach morphology and sedimentology at large scale coastal behaviour along the coastline of Santa Catarina, between Laguna and Sao Francisco Island, a microtidal east coast swell environment with headland and bay geomorphologies. The parabolic bay shape equation has proven to be a convenient and practical tool for studying the stability of the headland-bay beaches, tombolos, and salients in Santa Catarina. The beaches exhibit different patterns of sediment removal as a function of the degree of beach curvature. In highly curved beaches, there is a well-developed shadow zone and a range of morphodynamic conditions, from a sheltered low-energy beach adjacent to the downdrift headland to a high-energy exposed beach on the straight end of the headland-bay beach. The less curved beaches instead, tend to show more uniform behaviour since they are directly exposed to incident waves. There is no obvious relationship between average wave height and mean grain size, showing the importance of sediment source to characterize the sedimentary distribution patterns in the study area. The analysis of beaches showed that beach morphodynamics and sequence profiles for a bay-headland coast in a microtidal east coast environment is a function of geological inheritance (e.g., distance between headlands and orientation, nearshore and inner shelf morphology, coastal plain morphology, and sediment source), and hydrodynamic factors (wave conditions, oceanic wave exposure and relative tidal range). (C) 2009 Elsevier B.V. All rights reserved.
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The relative growth and population structure of the terebellid Nicolea uspiana were investigated in the intertidal zone of a rocky shore on the south-east coast of Brazil, from May 2006 to May 2007. Eight hundred and forty-seven individuals of N. uspiana were analysed: 391 males, 163 females, and 293 immatures. Although significant differences in some morphometric parameters were found, there was no sexual dimorphism between males and females. There were differences in total length, width of segments, and length of the notopodial region between matures and immatures. The negative allometry of the total length in relation to five other parameters showed that this feature is a good measure for estimating the individual size, which was then used in the analysis of population structure. This population of N. uspiana showed a bimodal size frequency distribution, with immature and mature individuals found during the entire year. This pattern indicates continuous reproduction, with each cohort growing for at least three to four months and being responsible for two consecutive settlement peaks.
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The Restinga of Marambaia is an emerged sand bar located between the Sepetiba Bay and the South Atlantic Ocean, on the south-east coast of Brazil. The objective of this study was to observe the geomorphologic evolution of the coastal zone of the Restinga of Marambaia using multitemporal satellite images acquired by multisensors from 1975 to 2004. The images were digitally segmented by a region growth algorithm and submitted to an unsupervised classification procedure (ISOSEG) followed by a raster edit based on visual interpretation. The image time-series showed a general trend of decrease in the total sand bar area with values varying from 80.61km(2) in 1975 to 78.15km(2) in 2004. The total area calculation based on the 1975 and 1978 Landsat MSS data was shown to be super-estimated in relation to the Landsat TM, Landsat ETM+, and CBERS-2 CCD data. These differences can also be associated to the relatively poorer spatial resolution of the MSS data, nominally 79m, against the 20m of the CCD data and 30m of the TM and ETM+ data. For the estimates of the width in the central portion of the sand bar the variation was from 158m (1975) to 100m (2004). The formation of a spit in the northern region of the study area was visually observed. The area of the spit was estimated, with values varying from 0.82km(2) (1975) to 0.55km(2) (2004).
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This thesis deals with physical factors and biological interactions affecting the distribution of two fucoid species, Fucus vesiculosus and F. serratus, in the Baltic Sea. Studies have been carried out in two quite different environments: an archipelago, and an open rocky coast. The archipelago has an extremely long coastline with a heterogeneous submerged landscape of different substrate types, slopes, water qualities, and degrees of wave exposure. The factors influencing F. vesiculosus distribution, morphology and epiphyte composition were studied in the Stockholm archipelago using field surveys and spatial modelling in Geographic information systems (GIS). A GIS-method to estimate wave exposure was developed and validated by comparing the result to an index based on vertical zonation of lichens. Wave exposure was considered an important factor for predicting the distribution of F. vesiculosus by its ability to clean hard surfaces from silt, and a predictive model was constructed based on the information of wave exposure and slope of the shore. It is suggested that the lower distribution boundary of attached F. vesiculosus is set by sediment in sheltered parts of the archipelago, and by light availability in highly wave exposed parts. The morphology of F. vesiculosus was studied over a wave exposure gradient, and several characters responded in accordance with earlier studies. However, when separating effects of wave exposure from effects of other confounding water property parameters, only thallus width was significantly different. Several water property parameters were shown to be correlated with wave exposure in the Stockholm archipelago, and the mechanism responsible for the effects on F. vesiculosus morphology is discussed. The composition of epiphytes on F. vesiculosus varied over a wave exposure gradient with a positive correlation to Elachista fucicola, and a negative to Chorda filum. At an open coast the physical environment is much less heterogeneous compared to an archipelago. The distributions of F. vesiculosus, F. serratus, turf-forming algae, and the seafloor substrate, were surveyed along the open coasts of Öland and Gotland. Turf-forming algae dominated all hard substrates in the area, and Polysiphonia fucoides was most abundant. At the Gotland coast F. vesiculosus was less abundant than at the Öland coast, and F. serratus occurred only in the southern-most part. Fucus serratus was increasingly more common towards south which was interpreted as an effect mainly of the Baltic salinity gradient, or the variation of salinity that has occurred in the past. The effects of turf-forming algae and sediment on F. serratus recruitment at 7 m depth off the Öland east coast were studied in the field, and by laboratory experiments. Almost no recruits were found in the algal turf outside the F. serratus patches. More fine sediment was found in the turf than in the F. serratus patches, suggesting that the turf accumulates sediment by decreasing resuspension. Both filamentous algae and sediment decreased the attachment ability of F. serratus zygotes and survival of recruits, and sediment had the strongest effect. It is therefore suggested that F. serratus has difficulties recruiting outside its patches, and that these difficulties are enforced by the eutrophication of the Baltic Sea, which has favoured growth of filamentous algae and increased sedimentation. An overall conclusion is that Fucus distribution is affected by large-scale-factors, such as the eutrophication and salinity changes of the Baltic Sea, as well as by small-scale variation in wave exposure, substrate and slope, and by surface competition with neighbouring species.
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Máster en Oceanografía
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In dieser Arbeit wird eine Methode entwickelt, die Rossbywellenzüge automatisch identifiziert und und deren Eigenschaften quantifiziert. Mit dieser Methode wird der Wellenzug als eine Einheit in Raum und Zeit interpretiert. Einheit im Raum heißt, dass nicht die einzelnen Tröge und Rücken eines Wellenzugs betrachtet werden, sondern deren Einhüllende. Einheit in der Zeit bedeutet, dass der Wellenzug nicht nur zu einem Zeitpunkt betrachtet wird, sondern über seine gesamte Lebensdauer hinweg. Um den Wellenzug als räumliche und zeitliche Einheit zu erhalten, werden die Einhüllenden der Wellenzüge in Längengrad-Zeit Diagrammen, sogenannten Hovmöllerdiagrammen, betrachtet. Dort werden zusammenhängende Regionen als Objekte, die jeweils einen Wellenzug repräsentieren, identifiziert. Deren Eigenschaften werden dann automatisch berechnet. Diese Eigenschaften können nun direkt dem zugrunde liegenden Rossbywellenzug zugeordnet werden.rnDie neue Methode wird in zwei verschiedenen Szenarien angewendet: erstens zur Beurteilung der Vorhersagequalität eines einzelnen Rossbywellenzugs und zweitens für die klimatologische Betrachtung von Rossbywellenzügen im ERA-40 Reanalysedatensatz. Sie wurde weiterhin mit bisher verwendeten Methoden zur Identifikation und Quantifizierung von Rossbywellenzügen verglichen.rnDie Untersuchung der Vorhersagequalität ergab, dass in dem betrachteten Fall die Übereinstimmung der Vorhersage mit der Analyse des Wellenzugs gering war, sofern das Modell initialisiert wurde, bevor der Rossbywellenzug eingesetzt hatte. Im Gegensatz dazu nahm die Vorhersagequalität deutlich zu, wenn der Wellenzug bereits in den Vorhersagedaten enthalten war. Dies deutet darauf hin, dass es in dem vorliegenden Fall problematisch ist, mit dem Modell den Auslösemechanismus korrekt voherzusagen. Für die weitere Untersuchung der Vorhersagequalität wurde eine spezielle Art der Darstellung der Daten verwendet, mit deren Hilfe deutlich wurde, dass das verwendete Modell in der Lage ist, diesen Wellenzug ungefähr sechs Tage im Voraus vorherzusagen. Diese Zeitspanne ist deutlich kürzer als die Lebensdauer des Wellenzugs, die etwa 10 Tage beträgt.rnIm Rahmen der klimatologischen Studie ergab sich eine positive Korrelation zwischen der Lebensdauer eines Rossbywellenzugs und des Bereichs den dieser Wellenzug während seiner gesamten Existenz in zonaler Richtung überstreicht. Für Wellenzüge mit einer kurzen Lebensdauer ergab sich eine ebenfalls positive Korrelation zwischen der mittleren Amplitude und der Dauer des Wellenzugs. Für eine längere Lebensdauer geht diese Korrelation aber in eine Sättigung über und die mittlere Amplitude steigt nicht mehr weiter an. Als eine mögliche Erklärung für dieses Verhalten wird angeführt, dass eine gewisse Stärke der Amplitude benötigt wird um stromabwärtige Entwicklung zu erhalten aber zu große Amplituden im Allgemeinen zum Brechen der Welle führen. Das Brechen leitet den letzten Abschnitt im Lebenszyklus eines Rossbywellenzuges ein, welcher im Anschluss meist zerfällt. Ein weiteres Ergebnis der klimatologischen Untersuchung ist das Auffinden bevorzugter Regionen der Entstehung und des Abklingens von Rossbywellenzügen. Diese Regionen unterscheiden sich erheblich für Rossbywellenzüge unterschiedlicher minimaler Lebensdauer. Langlebige Rossbywellenzüge entstehen demnach hauptsächlich über Ostasien und dem Westpazifik und vergehen dann über Europa.rnSchließlich wurde die entwickelte Methode in einen systematischen Vergleich anderer Methoden zur Identifikation und Quantifizierung von Rossbywellenzügen eingereiht. Die betrachteten Methoden beinhalten verschiedene Trog-und-Rücken Hovmöllerdiagramme des Meridionalwindes, Methoden die Rossbywellenzüge als eine Einheit identifizieren und Methoden die den Beitrag verschiedener physikalischer Aspekte zu der Entwicklung von Rossbywellenenzügen quantifizieren. Der Vergleich macht deutlich, dass jede Methode ihre individuellen Stärken und Schwächen hat. Dies bedeutet insbesondere, dass die Eignung der Methode von dem Stadium des Lebenszyklus, in dem sich der Rossbywellenzug befindet und dem Fokus, den man bei der Betrachtung hat, abhängt. Ideal ist eine Kombination mehrerer Methoden, da dies ein vollständigeres Bild eines Rossbywellenzuges ergibt als einzelne Methoden es zu liefern vermögen. Obwohl alle Methoden für die Anwendungen, für die sie jeweils konzipiert wurden, geeignet sind, ergeben sich bei der Diagnose der Rossbywellenzüge beträchtliche Unterschiede. Letztendlich stellt sich heraus, dass sogar die Defintion eines Rossbywellenzugs bis zu einem gewissen Grad von der zu seiner Identifizierung verwendeten Methode abhängt.
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In the present work, a detailed analysis of a Mediterranean TLC occurred in January 2014 has been conducted. The author is not aware of other studies regarding this particular event at the publication of this thesis. In order to outline the cyclone evolution, observational data, including weather-stations data, satellite data, radar data and photographic evidence, were collected at first. After having identified the cyclone path and its general features, the GLOBO, BOLAM and MOLOCH NWP models, developed at ISAC-CNR (Bologna), were used to simulate the phenomenon. Particular attention was paid on the Mediterranean phase as well as on the Atlantic phase, since the cyclone showed a well defined precursor up to 3 days before the minimum formation in the Alboran Sea. The Mediterranean phase has been studied using different combinations of GLOBO, BOLAM and MOLOCH models, so as to evaluate the best model chain to simulate this kind of phenomena. The BOLAM and MOLOCH models showed the best performance, by adjusting the path erroneously deviated in the National Centre for Environmental Prediction (NCEP) and ECMWF operational models. The analysis of the cyclone thermal phase shown the presence of a deep-warm core structure in many cases, thus confirming the tropical-like nature of the system. Furthermore, the results showed high sensitivity to initial conditions in the whole lifetime of the cyclone, while the Sea Surface Temperature (SST) modification leads only to small changes in the Adriatic phase. The Atlantic phase has been studied using GLOBO and BOLAM model and with the aid of the same methodology already developed. After tracing the precursor, in the form of a low-pressure system, from the American East Coast to Spain, the thermal phase analysis was conducted. The parameters obtained showed evidence of a deep-cold core asymmetric structure during the whole Atlantic phase, while the first contact with the Mediterranean Sea caused a sudden transition to a shallow-warm core structure. The examination of Potential Vorticity (PV) 3-dimensional structure revealed the presence of a PV streamer that individually formed over Greenland and eventually interacted with the low-pressure system over the Spanish coast, favouring the first phase of the cyclone baroclinic intensification. Finally, the development of an automated system that tracks and studies the thermal phase of Mediterranean cyclones has been encouraged. This could lead to the forecast of potential tropical transition, against with a minimum computational investment.
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Fin whale (Balaenoptera physalus) is the only misticeto commonly observed in the Mediterranean. The males emit sounds, classic pulse products in sequences called songs, at 20Hz for sexual purposes: sounds are produced during the spring for migration to the Tirreno-Ligurian-Provençal basin, the summer feeding area, and during the autumn, when there is a migration to the south to meet the winter breeding season. This area in the Mediterranean sea is unknown. The east coast of the Iberian Peninsula is a migration area. The study was conducted by analyzing through Adobe Audition 3.0 and XBAT softwares files audio of 30 minutes recorded in 2006, in 2011 and 2012 at the level of the Columbretes Islands, in the western Mediterranean sea, using two hearing aids: the MARU, used in 2006 and the EAR, used in 2011 and 2012. From the analysis have emerged that, in addition to songs with pulses of 20 Hz, there are new sounds of fin whale never previously recognized: the VFPs (Variable Frequency Pulses), higher-frequency pulses emitted, between 50 and 120Hz and the ramps, a set of 7-8 pulses, pertaining to a particular song, of increasing frequency. Further studies are needed to understand the importance of these new sounds.
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The red gorgonian Paramuricea clavata is considered a key species in Mediterranean coralligenous habitats and, when present at high density, its colonies may develop “gorgonian forests”, which are three-dimensional structures that increase habitat complexity. Mediterranean coralligenous habitats support high biodiversity but the structure and heterogeneity of communities can be strongly modified by several kinds of human-derived impacts. The global environmental change and human activity could threaten the coralligenous habitats and during the last few decades, Mediterranean suspension feeders have been involved in mass mortality events, in which P. clavata was one of the most affected. Without the complex three-dimensional structures formed by P. clavata, many benthic species may have not adequate sheltering and feeding opportunities. The aim of the present study was to investigate the ecological role of Paramuricea clavata in coralligenous habitats by comparing epibenthic assemblages established inside and outside gorgonian forests. This study was carried out in four sites randomly chosen, along the south-east coast of Elba island (north-western Mediterranean). The structure of the epibenthic assemblages were significantly different between area with and without gorgonians. Main differences concern very important taxa in the coralligenous bioconstruction processes like the encrusting red algae, Peyssonnelia spp. and Halimeda tuna, which were more abundant in presence of gorgonians. On the contrary, algal turf, mucilaginous algae and the invasive seaweed Caulerpa cylindracea were more abundant in areas without P. clavata. The presence of gorgonians may have a positive effect also on species diversity. The results of this study highlight the ecological role of P. clavata in the coralligenous habitats.
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During the lead-up to Montana second progressive era, Lee Metcalf and Forrest Anderson, along with others, kept the progressive flame lit in Montana. Metcalf’s political history is replete with close electoral wins because of his commitment to progressive ideals when the times were not always politically favorable for that. As State Legislator, MT Supreme Court Justice, Congressman and eventually as US Senator, Lee won races by as little as 55 votes because he stuck to his guns as a progressive. In Forrest Anderson’s career as a County Attorney, State Legislator, MT Supreme Court Justice and 12 years as MT Attorney General he was respected as a pragmatic practitioner of politics. But during that entire career leading up to his election as Governor, Forrest Anderson was also a stalwart supporter of the progressive agenda exemplified by FDR and the New Deal, which brought folks out of the Great Depression that was brought on by the bad policies of the GOP and big business. As MT’s second progressive period began in 1965, the first important election was Senator Metcalf’s successful re-election battle in 1966 with the sitting MT Governor, Tim Babcock. And the progressive express was really ignited by the election of Forrest Anderson as Governor in 1968 after 16 years of Republican Governors in MT. Gordon Bennett played a rather unique role, being a confidant of Metcalf and Anderson, both who respected his wide and varied experience, his intellect, and his roots in progressivism beginning with his formative years in the Red Corner of NE Montana. Working with Senator Metcalf and his team, including Brit Englund, Vic Reinemer, Peggy McLaughlin, Betty Davis and Jack Condon among others, Bennett helped shape the progressive message both in Washington DC and MT. Progressive labor and farm organizations, part of the progressive coalition, benefitted from Bennett’s advice and counsel and aided the Senator in his career including the huge challenge of having a sitting popular governor run against him for the Senate in 1966. Metcalf’s noted intern program produced a cadre of progressive leaders in Montana over the years. Most notably, Ron Richards transitioned from Metcalf Intern to Executive Secretary of the Montana Democratic Party (MDP) and assisted, along with Bennett, in the 1966 Metcalf-Babcock race in a big way. As Executive Secretary Richards was critical to the success of the MDP as a platform for Forrest Anderson’s general election run and win in 1968. After Forrest’s gubernatorial election, Richards became Executive Assistant (now called Chief of Staff) for Governor Anderson and also for Governor Thomas Judge. The Metcalf progressive strain, exemplified by many including Richards and Bennett, permeated Democratic politics during the second progressive era. So, too, did the coalition that supported Metcalf and his policies. The progressivism of the period of “In the Crucible of Change” was fired up by Lee Metcalf, Forrest Anderson and their supporters and coalitions, and Gordon Bennett was in the center of all of that, helping fire up the crucible, setting the stage for many policy advancements in both Washington DC and Montana. Gordon Bennett’s important role in the 1966 re-election of Senator Lee Metcalf and the 1968 election of Governor Forrest Anderson, as well as his wide experience in government and politics of that time allows him to provide us with an insider’s personal perspective of those races and other events at the beginning of the period of progressive change being documented “In the Crucible of Change,” as well as his personal insights into the larger political/policy picture of Montana. Gordon Bennett, a major and formative player “In the Crucible of Change,” was born in the far northeast town of Scobey, MT in 1922. He attended school in Scobey through the eighth grade and graduated from Helena High School. After attending Carroll College for two years, he received his BA in economics from Carleton College in Northfield, MN. During a brief stint on the east coast, his daily reading of the New York Times (“best newspaper in the world at that time … and now”) inspired him to pursue a career in journalism. He received his MA in Journalism from the University of Missouri and entered the field. As a reporter for the Great Falls Tribune under the ownership and management of the Warden Family, he observed and competed with the rigid control of Montana’s press by the Anaconda Company (the Great Falls Tribune was the only large newspaper in Montana NOT owned by ACM). Following his intellectual curiosity and his philosophical bend, he attended a number of Farm-Labor Institutes which he credits with motivating him to pursue solutions to economic and social woes through the law. In 1956, at the age of 34, he received his Juris Doctorate degree from the Georgetown University Law Center in Washington, DC. Bennett’s varied career included eighteen years as a farmer, four years in the US Army during WWII (1942-46), two years as Assistant MT Attorney General (1957-59) with Forrest Anderson, three years in private practice in Glasgow (1959-61), two years as Associate Solicitor in the Department of Interior in Washington, DC (1961-62), and private law practice in Helena from 1962 to 1969. While in Helena he was an unsuccessful candidate for the Montana Supreme Court (1962) and cemented his previous relationships with Attorney General Forrest Anderson and US Senator Lee Metcalf. Bennett modestly refuses to accept the title of Campaign Manager for either Lee Metcalf (1966 re-election over the challenger, MT Republican Governor Tim Babcock) or Forrest Anderson (his 1968 election as Governor), saying that “they ran their campaigns … we were only there to help.” But he has been generally recognized as having filled that critical role in both of those critical elections. After Governor Anderson’s election in 1968, Bennett was appointed Director of the MT Unemployment Compensation Commission, a position from where he could be a close advisor and confidant of the new Governor. In 1971, Governor Anderson appointed him Judge in the most important jurisdiction in Montana, the 1st Judicial District in Helena, a position he held for seventeen years (1971-88). Upon stepping down from his judgeship, for twenty years (1988-2008) he was a law instructor, mediator and arbitrator. He currently resides in Helena with his wife, Norma Tirrell, former newspaper reporter and researcher/writer. Bennett has two adult children and four grandchildren.
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This chapter examines some of the grammatical variability and non-standardness found in the English of the Falkland Islands. The Falklands are an archipelago of over 700 islands located in the western South Atlantic Ocean, 480km off the east coast of Argentina. Although the population is small – around 3000 - the islands cover an area of over 12000km2 – slightly larger than Jamaica and half the size of Wales, making them, after Greenland, the most sparsely populated political entity in the world. In political terms, the Falklands are an Overseas Territory of the United Kingdom. In contrast to the rural isolated image that the Falklands perhaps conjure up, the community is, in demographic terms, an urban and diverse one. Over 85% of the population living in the capital Stanley. The 2006 census (Government of the Falkland Islands 2007: 6) shows that 55% of the population were not born on the Islands, with the largest migrant groups coming from the UK, St Helena (another British Overseas Territory, located in the eastern South Atlantic), Chile and Australia. It also highlighted the fact that people born in 62 different countries were resident on the islands at the time (Pascoe and Pepper 2008: 38). By way of a comparison, only Monaco and Andorra, in Europe, have a higher proportion of their populations made up of migrants. In addition to the local Falkland population, there is a large military presence on the islands at the Royal Airforce Base at Mount Pleasant, 50km south-west of Stanley. The Head of State is the monarch of the UK, who is represented on the islands by a governor. The democratically elected 11-member Legislative Assembly is responsible for day-to-day government of the islands. The Falklands are perhaps most famous because of their 74 day occupation by Argentina in 1982. It is not appropriate here to go into detail about the dispute between the UK and Argentina about the sovereignty of the Islands. What is undisputed is that there has been a continuous Anglophone speech community on the islands since the early 1830s, making it one of the most recently developed ‘Inner Circle’ (Kachru 1985) Englishes in the world. This chapter examines the grammatical characteristics of Falkland Island English, drawn from a transcribed corpus of over 500,000 words of informal conversational speech, collected by Andrea Sudbury both in Stanley and in ‘Camp’ (the local name for the rest of the islands) (see Sudbury 2000, 2001 for more details about the methods used in the survey).
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A three-dimensional, regional coupled atmosphere-ocean model with full physics is developed to study air-sea interactions during winter storms off the U. S. east coast. Because of the scarcity of open ocean observations, models such as this offer valuable opportunities to investigate how oceanic forcing drives atmospheric circulation and vice versa. The study presented here considers conditions of strong atmospheric forcing (high wind speeds) and strong oceanic forcing (significant sea surface temperature (SST) gradients). A simulated atmospheric cyclone evolves in a manner consistent with Eta reanalysis, and the simulated air-sea heat and momentum exchanges strongly affect the circulations in both the atmosphere and the ocean. For the simulated cyclone of 19-20 January 1998, maximum ocean-to-atmosphere heat fluxes first appear over the Gulf Stream in the South Atlantic Bight, and this results in rapid deepening of the cyclone off the Carolina coast. As the cyclone moves eastward, the heat flux maximum shifts into the region near Cape Hatteras and later northeast of Hatteras, where it enhances the wind locally. The oceanic response to the atmospheric forcing is closely related to the wind direction. Southerly and southwesterly winds tend to strengthen surface currents in the Gulf Stream, whereas northeasterly winds weaken the surface currents in the Gulf Stream and generate southwestward flows on the shelf. The oceanic feedback to the atmosphere moderates the cyclone strength. Compared with a simulation in which the oceanic model always passes the initial SST to the atmospheric model, the coupled simulation in which the oceanic model passes the evolving SST to the atmospheric model produces higher ocean-to-atmosphere heat flux near Gulf Stream meander troughs. This is due to wind-driven lateral shifts of the stream, which in turn enhance the local northeasterly winds. Away from the Gulf Stream the coupled simulation produces surface winds that are 5 similar to 10% weaker. Differences in the surface ocean currents between these two experiments are significant on the shelf and in the open ocean.
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The Princeton Ocean Model is used to study the circulation in the Gulf of Maine and its seasonal transition in response to wind, surface heat flux, river discharge, and the M-2 tide. The model has an orthogonal-curvature linear grid in the horizontal with variable spacing from 3 km nearshore to 7 km offshore and 19 levels in the vertical. It is initialized and forced at the open boundary with model results from the East Coast Forecast System. The first experiment is forced by monthly climatological wind and heat flux from the Comprehensive Ocean Atmosphere Data Set; discharges from the Saint John, Penobscot, Kennebec, and Merrimack Rivers are added in the second experiment; the semidiurnal lunar tide (M-2) is included as part of the open boundary forcing in the third experiment. It is found that the surface heat flux plays an important role in regulating the annual cycle of the circulation in the Gulf of Maine. The spinup of the cyclonic circulation between April and June is likely caused by the differential heating between the interior gulf and the exterior shelf/slope region. From June to December the cyclonic circulation continues to strengthen, but gradually shrinks in size. When winter cooling erodes the stratification, the cyclonic circulation penetrates deeper into the water column. The circulation quickly spins down from December to February as most of the energy is consumed by bottom friction. While inclusion of river discharge changes details of the circulation pattern, the annual evolution of the circulation is largely unaffected. On the other hand, inclusion of the tide results in not only the anticyclonic circulation on Georges Bank but also modifications to the seasonal circulation.
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Worldwide, forests provide a wide variety of resources to rural inhabitants, and especially to the poor. In Madagascar, forest resources make important contributions to the livelihoods of the rural population living at the edges of these forests. Although people benefit from forest resources, forests are continuously cleared and converted into arable land. Despite long-term efforts on the part of researchers, development cooperation projects and government, Madagascar has not been able to achieve a fundamental decrease in deforestation. The question of why deforestation continues in spite of such efforts remains. To answer this question, we aimed at understanding deforestation and forest fragmentation from the perspective of rural households in the Manompana corridor on the east coast. Applying a sustainable livelihood approach, we explored local social-ecological systems to understand: (i) how livelihood strategies leading to deforestation evolve and (ii) how the decrease of forest impacts on households' strategies. Results highlight the complexity of the environmental, cultural and political context in which households’ decision-making takes place. Further, we found crucial impacts of deforestation and forest fragmentation on livelihood systems, but also recognized that people have been able to adapt to the changing landscapes without major impacts on their welfare.