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Höjdförändringar på Lomonosovfonna, Svalbard, 1996-2012Borg, Linnea January 2013 (has links)
The climate changes and the global warming have a great impact on the Arctic environments. This partially depends on that the albedo is getting lower when snow and ice is melting and exposes more and more dark surfaces of the land and sea. This leads to a feedback effect; the melting accelerates because dark surfaces attract more sun radiation. Because of the heating the glaciers in Arctic retreat. The purpose of this report is to obtain an eventual change in elevation on the glacier Lomonosovfonna that is located on Svalbard by comparing elevation data collected by NASA and GPS data from 1996-2012. The data was processed in ArcGIS and Matlab and the result is a change in elevation during the periods 1996-2012, 1996-2002 and 2002-2012. The result shows an average height decrease of Lomonosovfonna of -0,44 meters per year. When the result is reviewed, one can notice that both an increase and a decrease in height are observed on Lomonosovfonna. On the edge of the glacier, that border to Billefjorden, only a decrease in elevation is noticed. Some differences in elevation is very high in this area, and this can be due to three causes; the highest amount of melting occurs on the edges because of the higher air temperature at low elevation cause high melt, a calving have occurred or the difference is due to that the glacier is steepest in this area and therefore small position errors between measurements can cause big differences. The result also shows that the melting is accelerating, since the average melting of Lomonosovfonna was -0,26 meters per year during the period 1996-2002 and during the period 2002-2012 the melting had increased to -0,54 meters per year. The results are all in line with earlier measurements and reports and also with predictions for the climate. / Klimatförändringarna och den globala uppvärmningen slår hårt mot Arktis och områdena där omkring. Detta beror till stor del av att när snö och is smälter så försvinner ljusa ytor och ersätts av mörkt hav och land – albedot sänks. Detta har en feedbackeffekt som gör att smältningen accelererar eftersom att mörka ytor drar till sig mer solstrålning. På grund av uppvärmningen retirerar glaciärerna i Arktis, bland annat på Svalbard. Syftet för den här rapporten har varit att få fram eventuella höjdskillnader på Lomonosovfonnaglaciären på Svalbard genom att jämföra höjddata som samlats in under perioden 1996-2012. Datat består av altimeterdata insamlad av NASA och av GPS-data som samlats in av forskare på Uppsala universitet. Med hjälp av programmen ArcGIS och Matlab har ett resultat av höjdförändringarna kunnat tas fram från perioderna 1996-2012, 1996-2002 samt 2002-2012. Under hela mätperioden 1996-2012 var medelsänkningen av glaciären -0,44 meter per år. Resultatet visar att både sänkning och höjning har skett på glaciären. I kanten av Lomonosovfonna som gränsar mot Billefjorden har enbart en sänkning skett. Några av smältvärdena är mycket höga i denna del av glaciären, detta kan bero på flera saker; mest smältning sker i kanterna på grund av att glaciären är som tunnast där, en kalvning har sker och/eller så beror höjdskillnaden på att glaciären är som brantast i detta område och två mätpunkter från olika perioder som jämförts med varandra kan ligga på mycket olika höjd trots att de ligger nära varandra. Resultatet visar även att smältningen accelererar, eftersom medelsänkningen under perioden 1996-2002 låg på -0,26 meter per år medan den hade ökat till -0,54 meter per år under perioden 2002-2012. Resultaten som fåtts fram stämmer överens med tidigare mätningar och rapporter samt med de prognoser som finns över det framtida klimatet.
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Caracterização do meio físico em bacias hidrográficas com suportes de sensoriamento remoto e geoprocessamentoLeite, Bruno Souza [UNESP] 28 January 2013 (has links) (PDF)
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leite_bs_me_rcla.pdf: 1416877 bytes, checksum: 183434c3f4bc606bca230325462012c0 (MD5) / O presente trabalho buscou caracterizar o meio físico da sub-bacia do Ribeirão das Águas Claras, situado no estado de São Paulo, através da utilização de técnicas de Sensoriamento Remoto e Sistemas de Informações Geográficas (SIG). Para isso foram realizados trabalhos de gabinete e estudos de campo, onde ocorreu a coleta de dados primários; análise de bases cartográficas da região, com escalas de 1:50.000 e 1:10.000; análise de imagens de satélite, CBERS do ano de 2010; levantamentos de campo e mapeamento do uso e ocupação do solo e geração de mapas temáticos. Os resultados se materializaram na confecção de mapas temáticos que abarcaram a caracterização da geologia; geomorfologia; pedologia; declividade; pré-disposição aos processos riscos de erosão hídrica; perda do solo; uso e ocupação do solo; áreas de preservação permanente; além de caracterização da hidrografia local. Como conclusão, sugere-se a integração de técnicas de sensoriamento remoto e geoprocessamento como ferramentas importantes para a gestão do meio físico / This paper aims to characterize the physical environment of the Ribeirão das Águas Claras watershed, located at São Paulo state, through the use of Remote Sensing and Geographic Information Systems (GIS) techniques. For this aim it has been done office and field studies, where it occur secondary data collection; region cartography bases analysis, with 1:50.000 and 1:10.000 scales; satellite images analysis, from 2010 CBERS collection; field surveys and mapping of the field use and occupation and thematic maps creation. The results materializes in the production of thematic maps which covered the characterization of geology; geomorphology; pedology; slope; predisposition to erosion, soil loss, soil use and occupation; permanent preservation areas, as well as hydrograph characterization. The conclusion is suggest the integration of remote sensing techniques and geoprocessing as an important tools trough the sustainable management of the physical environment
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Proposta de sintese climatica a partir do comportamento termico e higrometrico do ar em areas urbanas / Proposal for climate summary from the behavior of heat and relative humidity of the air in urban areasJardim, Carlos Henrique 31 August 2007 (has links)
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Previous issue date: 2007 / Resumo: As modificações impostas pelas cidades ao comportamento dos elementos climáticos são insuficientes para a definição de um clima urbano. Mesmo num espaço relativamente pequeno, deve-se levar em consideração a influência de uma série de outros fenômenos climáticos, cuja gênese remonta a participação de fatores alheios à própria organização urbana. Com a finalidade de demonstrar isso, tendo como área de estudo a bacia hidrográfica do Rio Aricanduva na zona leste do município de São Paulo (SP), procurou-se avaliar a influência dos fatores geográficos de superfície no comportamento da temperatura e umidade relativa do ar em áreas urbanas, considerando como pressuposto a relação entre a sucessão dos tipos de tempo e as mudanças na configuração espacial desses elementos. Essas mudanças foram interpretadas, em seguida, como indicadoras do caráter ¿sistêmico¿ do clima. Os dados utilizados foram resgatados de trabalhos anteriores, além daqueles produzidos durante o desenvolvimento desta pesquisa entre 2004 e 2006. A análise envolveu o cruzamento dos dados mensurados com as características físicas do ambiente de coleta e do tipo de tempo no dia. Os resultados foram traduzidos numa série de cartas, com o propósito apresentar o fato geográfico-climatológico dentro da sua real dimensão de tempo e escala / Abstract: The modifications imposed by the cities to the behavior of the climatic elements are insufficient for the definition of an urban climate. Even in a space relatively small, it should be taken into account the influence of a series of other climatic phenomena, whose genesis raises the participation of factors strange to the own urban organization. With the purpose of demonstrating that, tends as study area Rio Aricanduva's basin in the area east of the municipal district of São Paulo (SP), it tried to evaluate the influence of the geographical factors of surface in the behavior of the temperature and relative humidity of the air in urban areas, considering as presupposition the relationship between the succession of the atmospheric states and the changes in the space configuration of those elements. Those changes were interpreted, soon afterwards, as indicative of the "systemic" character of the climate. The used data were rescued of previous works, besides those produced during the development of this research between 2004 and 2006. The analysis involved the crossing of the data measured with the physical characteristics of the collection atmosphere and of the meteorological conditions of the day. The results were translated in a series of maps, with the purpose to present the geographical-climatological fact inside of her real space dimension and time / Doutorado / Análise Ambiental e Dinâmica Territorial / Doutor em Ciências
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Three-dimensional modeling of Quaternary sediments and valley morphology, Bollnäs, Sweden.Nord, Veronica January 2014 (has links)
This study demonstrates how to make and use a three dimensional model in GSI3D, based on well data from the Geological Survey of Sweden’s well archive. The objective is to determine if it is possible to show a supposed fault scarp, the Bollnäs fault, in the bedrock and the valley morphology in a 3D model based on the data available. During the last ice age, the land surface under the ice was depressed by several hundred meters. As the last ice sheet retreated, land uplift began and faulting occurred. These glacially-induced faults are dated to late or post glacial times since they are cutting post glacial sediments. The same goes for the Bollnäs fault. The scarp is seen through airborne light detecting and ranging, LiDAR, cutting surficial sediments but never outcrops in the bedrock. After examining and validating the well data in the mapped area, 430 of 478 wells were used to build the model, giving a 3D model of the surficial deposits and the bedrock surface. In the model, the scarp cannot be seen in the bedrock, nor in the deposits nor in the valley morphology. Exporting the model to Arc GIS as a digital terrain model, a DTM, as a raster, shows that with the amount of data available a fair pixel resolution would be 150 m2. With that resolution detailed landforms like fault scarps would not appear. The conclusion is that the amount of data is to low to accurately model small-scale features. These findings aligning with earlier research on 3D models.
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Geomorfologisk kartläggnng av Kungsbäckens avrinningsområdeSjö, Maria, Tähtikivi, Annelie January 2006 (has links)
År 2015 ska alla avrinningsområden i EU-länderna vara fastställda. Anledningen till detta är att år 2000 trädde ett vattendirektiv i kraft. Syftet med direktivet är att skapa en helhetssyn för vattenresurserna i Europa och för att få en enhetlig och övergripande lagstiftning. I Sverige har SMHI redan bestämt vattendelare och avrinningsområden för ett stort antal områden i landet, men i och med direktivet har det blivit ett krav. En helhetssyn på vattenresurser tillsammans med kunskaper om geologi är en förutsättning för en hållbar utveckling och ett effektivt tillvaratagande av naturresurserna. Inom samhällsplaneringen spelar geologin en tämligen betydande roll. Vid exempelvis planering av nya bostadsområden är det av stor vikt att veta markens egenskaper. Syftet med detta examensarbete var att fastställa Kungsbäckens avrinningsområde samt att göra en geomorfologisk undersökning av området. Arbetet syftade även till att redogöra för några fluvialmorfologiska förekomster kring del av Kungsbäcken - från utloppet vid Gavleån vid Stora Vall till viadukten vid Regementsvägen. Genom att utföra studien som en kombination av naturgeografi och GIT påvisas möjligheterna att utföra olika typer av analyser och beräkningar utifrån de naturresurser som finns i ett område och den moderna tekniken. Vidare kommer resultatet från denna studie att delges SMHI. De kan därmed få nytta av materialet när de, på uppdrag av Naturvårdsverket, skall utföra en kartläggning av Kungsbäckens avrinningsområde. För att möjliggöra en geomorfologisk kartläggning av Kungsbäckens avrinningsområde och fastställa dess gränser studerades initialt tillgängligt material såsom tidigare studier, litteratur, terrängkarta, jord- och bergartskartor samt flygfotografier. Vid genomförandet av fastställningen av områdets gränser nyttjades bland annat SMHI:s tidigare gjorda gränser, en av oss gjord analog analys, utifrån tryckta terrängkartan 13H SV samt en flödesmodellering av en i studien gjord höjdmodell över området. Därefter gjordes fältstudier till tre stycken områden med osäkra områdesgränser, vilka framkom av ovan nämnda analyser. Med hjälp av flödesriktningsinstrument och okulär besiktning kunde gränserna då fastställas. Även fältstudier av geomorfologiskt intresse har utförts, såsom studie av ändmoräner och hällar. Med hjälp av genomförda fältstudier, analyser, digitalisering och litteraturgranskning har gränserna för Kungsbäckens avrinningsområde bestämts samt beräknats till en area av 105,4 km2. Områdets geomorfologiska kartläggning har resulterat i en karta där de olika förekomsterna finns redovisade (se bilaga 1, karta i A3-format). Förutom detta finns olika begrepp och naturfenomen beskrivna i rapporten samt nyttan med denna typ av studie. / In year 2000, the EU Water Framework Directive was adopted and by 2015, all European watersheds have to be established. The purpose with the directive is to create an overall view over the water resources in Europe and to get a comprehensive legislation. SMHI in Sweden has already established a few watersheds around the country. An overall view of the water resources together with knowledge of the geology is a requirement to a sustainable development and an effective taking care of the nature resources. Within the physical planning, the geology knowledge is very important. For example, it is vital to know the quality of the ground when planning new building complexes. The purpose with this bachelor thesis was to establish the watershed of Kungsbäcken and to do a geomorphologic survey of the area. The thesis also aimed to describe some of the fluvial morphologic presences, in a part of Kungsbäcken, i.e. from the outflow to Gavleån at Stora Vall, to the viaduct at Regementvägen. By doing the study as a combination of physical geography and GIT, the possibilities to do different types of analyses and calculations, on the basis of the nature resources in an area and the modern technique are pointed out. Furthermore, the result from this study will be given to SMHI. The result may be of benefit to SMHI, when mapping the watershed of Kungsbäcken later on. To make the geomorphologic survey of the watershed and to establish the boundaries of it, literature, earlier studies in the area, terrain- , rock, - soil maps and aerial photos were studied. Moreover, out of date-boundaries established by SMHI were used, together with an analogue analysis, based on the printed terrain map 13H SV. We also used a flow model, based on a digital elevation model over the area. The study also contained field trips. Three areas with uncertain boundaries were studied and with flow direction instruments and ocular examination, the boundaries were established. Field trips of geomorphologic interest were also made, like studies of recessional moraine and roch moutonnée. By field trips, analyses, digitizing and literature perusal, the boundaries of the watershed of Kungsbäcken has been established and the area is 105.4 km2. The result of the geomorphologic survey of the area can be seen in a map (appendix 1). Apart from that, concepts and nature phenomena are also described in the report along with observations of the benefits of studies like this one.
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Assessing the ability of HEC-HMS rainfall-runoff model to simulate stream flow across SwedenAlavimoghaddam, Mohammadreza January 2017 (has links)
Computer modeling is the powerful tool for simulating nature’s behavior; however, still more efforts are need for reaching perfect simulation with computer models (especially in the hydrological field of study). In this Master’s thesis, the accuracy of the HEC-HMS computer model for long term rainfall-runoff simulation was evaluated across Sweden. Five different catchments from north to south of Sweden were selected and then simulation have done for 34 years of available data. Simulation was conducted using daily, monthly and yearly time scale resolutions. Results from the north to the south of Sweden were completely different. Simulated runoff and observed runoff in northern catchments followed the same pattern over different time scales but in the southern part of Sweden the results had different patterns in space and time. The best results with HEC-HMS were found in the northern catchments with steep main river slopes. In the southern catchments the model could not predict runoff in any realistic manner at any time and space scale. In total the HEC-HMS model cannot simulate the rainfall runoff for long periods of simulation across Sweden. This is especially true in southern parts of the country dominate with low elevation catchments. However, with regards to its ability for event-based simulation HEC-HMS could be a suitable tool to simulate flood event discharges that are needed for road or other hydraulic structures designs. But, this would require significant amounts of calibration and model development.
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The Vegetational and Environmental Development of Lina Mire, Gotland from 6900-400 BCStrandberg, Nichola January 2017 (has links)
Lina Mire, Gotland, is an area of archaeological significance and has a complex history of shoreline displacement. Archaeologists suspect that Lina Mire was once part of an important inland water system which connected the Littorina Sea with central Gotland. This study investigates vegetational and palaeoenvironmental changes of the Lina Mire area between 6900 – 400 BC (8850 – 2350 cal years BP) in order to better understand how the area has developed and how humans have impacted the vegetation. Pollen analysis, C/N ratios, organic matter and carbon content measurements were conducted. The chronology was based on 14C AMS dating of terrestrial macrofossils and bulk sediments. A transgression of the Littorina Sea at about 6550 BC (8500 cal years BP) inundated the Lina Mire basin, which was a lake at the time. The onset of cultivation was indicated by the presence of Hordeum (Barley or Wild Barley) during the Late Neolithic, 2630 BC (4580 cal years BP). Hordeum continued to grow during the Bronze Age when Cereals appeared at about 970 BC (2920 cal years BP). During the onset of cultivation during the Late Neolithic, the Lina Mire basin was a bay of the Littorina Sea. The Lina Mire basin remained connected with the Littorina Sea until isostatic uplift caused it to become isolated at about 1870 BC (3820 cal years BP). The lake overgrew and became a mire about 820 BC (2770 cal years BP).
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Landskapsklassificering av Avanäset, FåröVainionpää Lindgren, Elin January 2018 (has links)
På Avanäset, Fårö, har naturliga processer skapat ett unikt landskap som domineras av flygsand och långa sandstränder. Denna studie har syftet att klassificera och kartera Avanäsets flygsandsområde och genom detta skapa en landskapsklassificeringskarta på Avanäset. Landskapsklassificeringen utgår från ett integrerat kulturgeografiskt och naturgeografiskt perspektiv för att göra en helhetsklassificering över området. Den överliggande metoden till klassificeringen är en hierarkisk metod, genom att skapa en klassificering med flera lager, från topografi och flygsanden/berggrunden som baslager och arbeta sig upp genom geomorfologiska formerna till mänsklig aktivitet på översta lagret. Arbetet med klassificeringen har gjorts genom användandet av ett GIS-system som tillåter skapande av avancerade kartproduktioner med flera lager. Flygsanden delas in i tre landskapsenheter där det största området på Avanäset upptas av sekundära flygsandslandskap. På det sekundära flygsandslandskapet hittas de dynformationer såsom parabeldyner som är typiska för landskapsenheten. Det primära flygsandslandskapet är skapat vid kustlinjen där den befinner sig idag eller har befunnit sig under Avanäsets utveckling. Det primära flygsandslandskapet domineras av linjära dynformationer, så kallade ’foredunes’. Det minsta området är agrarlandskap på flygsand som är präglat av människornas användning av flygsandsladskapet. Här syns spåren genom utplanade dynformationer där marken använts till lantbruket. Förutom flygsanden återfinns även mindre områden av kalkstensuddar och strandvallsavlagringar på Avanäset.
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High-resolution mapping of soil organic carbon storage and soil properties in Siberian periglacial terrainSiewert, Matthias January 2015 (has links)
In the past years considerable attention has been given to soil organic carbon (SOC) stored in permafrost-affected soils in periglacial terrain. Studies have shown that these soils store around half the global SOC pool, making them a key component of the global carbon cycle. Much of the SOC presently stored in these soils has accumulated since the Pleistocene and is protected from decomposition and erosion by low temperatures close to or below the freezing point. This makes it vulnerable to remobilization under a warming climate. This thesis provides new data on SOC storage in three study areas in Siberian periglacial terrain. A high-resolution land cover classification (LCC) for each study area is used to perform detailed vertical and spatial partitioning of SOC. The results show that the vast majority (>86%) of the ecosystem carbon is stored in the top meter of soil. Low relative storage of carbon in plant phytomass indicates limited uptake potential by vegetation and emphasises the vulnerability of the SOC pool to geomorphic changes. Peat formation as well as cryoturbation are identified as the two main pedogenic processes leading to accumulation of SOC. Presence or absence of ice-rich Yedoma deposits determine soil formation and SOC storage at landscape scale. At local scale, periglacial landforms dominate SOC allocation in the tundra, while forest ecosystem dynamics and catenary position control SOC storage in the taiga. A large diversity of soil types is found in these environments and soil properties within pedons can be highly variable with depth. High-resolution satellite imagery allows upscaling of the SOC storage at unprecedented detail, but replication of soil pedons is a limiting factor for mapping of SOC in remote periglacial regions. Future research must look beyond traditional LCC approaches and investigate additional data-sources such as digital elevation models. The concept of state factors of soil formation is advocated as a framework to investigate present day and future SOC allocation in periglacial terrain.
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Using a lumped conceptual hydrological model for five different catchments in SwedenEkenberg, Madeleine January 2016 (has links)
Hydrological models offer powerful tools for understanding and predicting. In this thesis we havereviewed the advantages and disadvantages of physically based distributed hydrological models andconceptually lumped hydrological models. Based on that review, we went into depth and developed aMATLAB code to test if a simple conceptual lumped hydrological model, namely GR2M, wouldperform satisfactory for five different catchments in different parts of Sweden. The model had ratherunsatisfactory results and underestimated runoff systematically throughout all the five catchments.Additions to the model structure, such as a buffer allowing an approximation for snowmelt delay, wereintroduced with varying degrees of success. Based on analytical exploration of the model theory, it canbe seen that the instability of the model is mainly caused by one of the two free parameters used inGR2M, namely the maximum soil storage capacity. The optimization method used showed lowsensitivity to changes in this parameter while the calculated soil storage had strong dependence on thisparameter. Based on these results, it is fair to say that a simple lumped model likely does not have theability to represent the full range of hydrological conditions found along the gradient of Sweden.
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