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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Globally Extended Kppen-Geiger Climate Classification and Temporal Shifts in Terrestrial Climatic Types

Rohli, Robert V., Joyner, T., Reynolds, Stephen J., Shaw, Cynthia, Vázquez, Javier R. 04 March 2015 (has links)
Increasing awareness of the impacts of global climate change on marine ecosystems and concerns about shifting bioclimatic and agricultural zones necessitate a reassessment of the geographical distribution of Earths climate types. In recent years, the availability of truly global data-sets has allowed for the application of climatic types, including the Kppen-Geiger system, over the oceans. This research uses NCAR Reanalysis data to create a global Extended Kppen-Geiger climate classification, including the world ocean, for the 1981-2010 averaging period. The percentages of Earths surface covered by tropical rainforest (Af), tropical monsoon (Am), and (especially) the mesothermal-mild summer (Cfc) climate types are much larger than in the terrestrial only analysis. Expanding and contracting terrestrial climate zones are also identified based on the differences in the total area through comparison with maps produced for 1901-1925, 1926-1950, 1951-1975, 1976-2000 and model-output-based predicted Kppen-Geiger types for 2076-2100. Results suggest that hot desert (BWh), hot semi-arid (BSh), and Af climatic types are projected to expand, while the tundra and most mesothermal and microthermal types will decrease in area. These results assist in projecting global impacts of climatic change.
2

Overlap of Global Köppen-Geiger Climates, Biomes, and Soil Orders

Rohli, Robert V., Joyner, T. Andrew, Reynolds, Stephen J., Ballinger, Thomas J. 04 March 2015 (has links)
Climate types, biome types, and soil orders are commonly used among physical geographers in research and to describe natural environmental characteristics. However, little attempt has been made to quantify the percentage of global land surface that is covered by combinations of climate types, biomes, and soil orders. This research overlays a world map of 31 climate types produced based on the Köppen-Geiger criteria using gridded NCAR/NCEP reanalysis monthly mean surface air temperature and precipitation data from 1981 to 2010 with global maps of eight biomes adapted from World Wildlife Federation and 12 soil orders from United States Natural Resources Conservation Service. Areas covered by each of the 2976 combinations are then calculated. Results suggest that, as expected, a few climate/biome/soil combinations are most common, such as desert climate/desert biome/entisols, tundra climate/tundra biome/gelisols, and desert climate/desert biome/aridisols. The local nature of soil properties causes small enclaves of unexpected combinations of climate, biome, and soils, and the 10 most extensive climate/biome/soil combinations occupy only one-quarter of the global land surface. The strong correspondence between climate and biome types validates the Köppen-Geiger criteria for categorizing climates based on vegetation realms, even today, despite the general paucity of data available when the criteria were established.
3

Estudo de parâmetros climáticos como subsídio à gestão ambiental da vertente paranaense da bacia hidrográfica do rio Itararé / Study of climatic parameters as subsidy to environmental management of the Paraná State slope of Itararé watershed

Terassi, Paulo Miguel de Bodas [UNESP] 18 December 2015 (has links)
Submitted by Paulo Miguel de Bodas Terassi (pmbterassi@gmail.com) on 2016-01-14T11:33:09Z No. of bitstreams: 1 Estudo de parâmetros climáticos como subsídio à gestão ambiental da vertente paraense da bacia hidrográfica do rio Itararé (Finalizada)..pdf: 10553168 bytes, checksum: 546a90aadd733a630cc8b09187e65591 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-01-14T13:58:37Z (GMT) No. of bitstreams: 1 terassi_pmb_me_prud.pdf: 10553168 bytes, checksum: 546a90aadd733a630cc8b09187e65591 (MD5) / Made available in DSpace on 2016-01-14T13:58:37Z (GMT). No. of bitstreams: 1 terassi_pmb_me_prud.pdf: 10553168 bytes, checksum: 546a90aadd733a630cc8b09187e65591 (MD5) Previous issue date: 2015-12-18 / Não recebi financiamento / Os estudos dos aspectos físicos e sociais existentes em bacias hidrográficas permitem avaliar os seus diversos componentes, os processos e interações que nela ocorrem. Sobretudo, o clima funciona como um insumo de energia para a bacia hidrográfica e desempenha o papel de controlar ou influenciar diversos componentes da dinâmica socioambiental desse recorte espacial. Nessa perspectiva, o presente trabalho objetiva o estudo das características climáticas e, especificamente o conhecimento do comportamento da erosividade das chuvas e da disponibilidade hídrica na vertente paranaense da bacia hidrográfica do rio Itararé. O recorte de estudo está situado nos setores nordeste e leste do Paraná e abrange uma superfície aproximada de 4.845 km2. Foram obtidos os dados anuais, sazonais, mensais e diários de chuva de treze postos pluviométricos junto ao Instituto das Águas do Paraná e de uma estação meteorológica, de Joaquim Távora, pertencente ao Instituto Agronômico do Paraná. Foram utilizadas as seguintes metodologias: aplicou-se o índice de erosividade de Rufino, Biscaia e Merten (1993); espacializou-se as estimativas de temperatura fornecidas pela Universidade de Delaware (2014); empregou-se o balanço hídrico climatológico de Thornthwaite e Mather (1955); foram aplicados os sistemas de classificação climática de Köppen (1948), Thornthwaite (1948) e Nimer (1972); e, por fim, empregou-se a técnica de agrupamento para a obtenção de regiões homogêneas e para a definição de anos-padrão. Observou-se que embora tenham sido observados alguns padrões entre o efeito orográfico e o aumento de pluviosidade em alguns setores da bacia hidrográfica, a distribuição das isolinhas de pluviosidade e número de dias de chuva para a escala anual está propriamente mais ligada às diferenças entre o regime pluviométrico sazonal e a interferência da dinâmica atmosférica regional. Identificou-se que as maiores alturas pluviométricas ocorrem durante o período que vai de setembro a março, período de ocorrência do maior potencial erosivo. As maiores isotermas, os maiores valores de evapotranspiração e menores valores de excedente hídrico foram identificados para o setor norte, com um cenário inverso para os setores sul e oeste. O emprego do sistema de classificação climática de Köppen (1948) possibilitou delimitar a área de estudo em três tipologias climáticas: Cfb para os setores oeste e central; Cfa para o setor norte; Cfa/Cfb para os setores transitórios. A metodologia de Thornthwaite (1948) apresentou seis tipologias climáticas distinguindo apropriadamente as características climáticas da bacia hidrográfica em conformidade com o índice de umidade efetiva e a eficiência térmica. A metodologia de Nimer (1972) identificou três tipologias climáticas e definiu características da circulação atmosférica a partir dos atributos climáticos. O zoneamento climático permitiu averiguar a relação das características climáticas com os componentes socioambientais da área de estudo. A zona climática IV merece atenção por ter apresentado a maior erosividade das chuvas, junto à verificação de solo exposto associado a elevadas declividades, fatores que representam maiores riscos à erosão. A zona climática I apresenta a significativa ocupação por pastagens e lavouras temporárias e, o alerta da possibilidade de deficiência hídrica, especialmente em condições de La Niña ou em meses como abril e agosto, demonstram uma vulnerabilidade a essas atividades econômicas. / The studies of the physical and social aspects present in a watershed allow us to evaluate their various components, their processes and interactions that occur in it. Above all, the climate works as an energy input to the watershed and plays the role of controlling and influencing various components of the dynamics socio-environmental of this spatial cutout. From this perspective, the present study aims to study the climatic characteristics and specifically the knowledge of the behavior of rainfall erosivity and water availability in the watershed Itararé, in Parana state. The study clipping is situated in the northeast and eastern sectors of Paraná and covers an area of approximately 4,845 km2. Annual, seasonal, monthly and daily rain data of thirteen rain gauge stations were obtained along with the Paraná Institute of Water and the weather station Joaquim Távora, which belongs to the Agronomic Institute of Paraná. The following methodologies were used: erosivity indices of Rufino, Biscaia and Merten (1993); Temperature estimates provided by the University of Delaware (2014); climatic water balance of Thornthwaite and Mather (1955); Climate classification system of Köppen (1948), Thornthwaite (1948) and Nimer (1972) and, lastly, a clustering technique for obtaining homogeneous regions and to define standard-years was used. It was noticed that although some patterns between the orographic effect and the increase of pluviosity in some sectors of the watershed were observed, the distribution of isoline rainfall and the number of rainy days for the annual range is more properly related to the differences between seasonal rainfall and the interference of regional atmospheric dynamics. It was identified that the highest rainfall occur during the period from September to March, which is the period of occurrence of the most erosive potential. The biggest isotherms, the highest evapotranspiration values and lower water surplus values were identified for the northern sector, with a reverse scenario to the south and west sectors. The usage of Köppen‟s classification system (1948) allowed us to define the study area into three climatic types: Cfb for the western and central sectors; Cfa for the northern sector; Cfa / Cfb for transient sectors. The methodology presented by Thornthwaite (1948) exposed six climate types, properly distinguishing the climatic characteristics of the watershed in accordance with the effective moisture and thermal efficiency. Nimer‟s methodology (1972) identified three climate types and defined the atmospheric circulation features through the climatic attributes. The climatic zoning made it possible to examine the relation between the climatic characteristics and the social-environmental components of the study area. The climate zone IV requires attention for presenting the highest rainfall erosivity besides the exposed soil associated with high declivities, factors that evince the greatest risk to erosion. The climate zona I presents significant occupancy of pastures and temporary crops, and the warning of the possibility of deficiency water, especially in La Niña conditions or months like April and August, demonstrate a vulnerability to these economic activities.

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