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Implementation and evaluation of the Pitman model in seasonal hydrological forecasting mode using the Kraai River catchment in Eastern Cape South Africa as a case studyFikileni, Sesethu 25 January 2021 (has links)
Seasonal hydrologic extremes such as drought and floods have devastating impacts on human and natural systems (e.g. 2015-2017 Western Cape drought). Sentence has been reworded to: Therefore, the need for a reliable seasonal hydrologic forecast is significant and becoming even more urgent under future climate, as the assimilation of seasonal forecast information in decision making. Hence, SHF becomes part of the short and long-term climate change adaptation strategies in a range of contexts such as energy supply, water supply and management, rural-urban, agriculture, infrastructure and disaster preparedness and relief. This work deals with implementation and evaluation of the Pitman/Water Resources Simulation Model 2012 model (WR2012) in seasonal hydrological forecasting mode. The aim of the study is to improve the understanding of seasonal hydrological forecasting by evaluating the performance of a hydrological model (Pitman Model) in the seasonal forecast mode in Kraai River tertiary catchment (D13) as a case study and the objectives are: To determine steps to be undertaken to implement integration of Pitman in WR2012 configuration with climate forecast to generate seasonal hydrological forecast and to evaluate the performance of the model forced by climate model data in the simulation and forecast mode. Pitman model in the WR2012 version works with a specific rainfall dataset spanning the period of 1920-2009. Operationalizing the seasonal hydrological forecast with Pitman model requires, therefore, updating of the WR2012 rainfall so that it extends to-date. To achieve that, two datasets were evaluated: Climate Hazards Group InfraRed Precipitation with Station Data (CHIRPS), which is a satellite-based gridded rainfall dataset, and rain gauge-based dataset from South African Weather Service (SAWS). The analyses revealed that CHIRPS rainfall data had better correlation and lower bias with respect to the WR2012 data when compared with SAWS rainfall data for the overlap period 1981-2009. The CHIRPS data showed no significant difference from the WR2012 in all the three rainfall zones of the Kraai River catchment. Therefore, CHIRPS data were used to extend the WR2012 data and were used as input to set up Pitman model/WR2012 in the seasonal hydrological forecasting mode. The Pitman/WR2012 model was forced with 10 ensemble seasonal climate forecast from Climate Forecast Systems v.2 which is downscaled using the Principal Components Regression (PCR) approach. The generated seasonal hydrological forecast focused on the summer season, in particular on the Dec-Jan-Feb (DJF) period, which is the rainy season in the catchment. The hydrological forecast showed skills more especially in Dec and Feb (assessed through ROC and RPSS forecast verification methods) with Jan having a poor skill. Importantly, the skill of streamflow forecast was better than that of rainfall forecast, which likely results from the influence of initial conditions of the hydrological model. In conclusion Pitman/WR2012 model can perform realistically when implemented in seasonal hydrological forecasts mode, and it is important that in that model, the model is run with near real time rainfall data in order to achieve good initial conditions. However, the results in terms of forecast skill are specific to the studied catchment and analysed forecast, and skill of forecast in any other catchment has to be investigated separately.
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Variations in Soil Fungi of Ten Representative Soils of Denton, County, TexasFloyd, Mary Louise 08 1900 (has links)
This study attempted to examine representative soils of Denton County in an effort to determine seasonal and soil type variations in the fungous flora both quantitatively and qualitatively.
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Development of an Interactive Model Predicting Climatological and Cultural Influences on Annual Groundwater Volume in the Mississippi Delta Shallow Alluvial AquiferMerrell, Tia Leni 02 May 2009 (has links)
Water volume in the shallow alluvial aquifer in the Mississippi Delta region is subject to seasonal declines and annual fluctuations caused by both climatological variability and crop water use variations from year-to-year. The most recently documented water volume decline in the aquifer is estimated at 500,000 acreeet. Available climate, crop acreage, irrigation water use, and groundwater decline data from Sunflower County, MS are used to evaluate the climate-groundwater interactions in the Mississippi Delta region. This research produced a model that simulates the effects of climatic variability, crop acreage changes, and specific irrigation methods on consequent variations in the water volume in the aquifer. Climatic variability is accounted for in the model by predicative equations that relate annual measured plant water use (irrigation) to growing season precipitation amounts. This derived relationship allows the application of a long-term climatological record to simulate the cumulative impact of climate on groundwater used for irrigation.
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Comparison of Tensiometer and Climatological Methods for Estimating Soil Moisture Depletion and Scheduling Irrigation for PotatoesWiser, Thayne B. 01 May 1972 (has links)
The purpose of this thesis was to compare the tensiometer and climatic methods of scheduling irrigation of potatoes under field conditions. Tensiometers were placed in a 160 acre field to maintain the crop within the optimum moisture range and schedule irrigations. An automatic solid set system was used to apply water to the potato crop. Instrumentation was used to determine daily input for the climatological method. Daily evapotranspiration (Et) was computed and Et (tensiometer) was comPared with Et (climatic). The results showed total variation of the climatic method from the tensiometer method of .62 inches or less than 5 per cent. The study indicated that the climatological method would have under irrigated the potato crop by . 62 inches during the 48 day study. Variations are also shown for each irrigation interval. Results indicated that a combination of both methods would allow the most feasible approach to scheduling irrigation of potatoes.
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Zpracování klimatologických měření z experimentálních lokalit v Kyrgyzstánu a jejich synopticko-klimatologická interpretace / The Processing of Climatologic Records from Experimental Locations in Kyrgyzstan and the Synoptic-climatologic Interpretation ThereofSýkorová, Petra January 2016 (has links)
The Charles University Faculty of Science KFGG team took part in an intensive research in the area of Kyrgyz glacial lakes. The collecting of records from three meteorological stations in the locations of Kolor (2,700 m above sea level) and Adygine (3,500 and 3,800 meters above sea level) was part of the research. The aim of this thesis was to analyze the homogeneity of climatic data measured in experimental locations using the SNHT method (Standard Normal Homogeneity Test), process the data using general climatological processes, create a classification of circulation types for the area of interest using Jenkinson's and Collinson's method, and finally, to quantify the relationships between individual circulation types and the values of chosen climatic elements. The analysis results are homogenized climatic sets for the Adygine H station (3,800 m above sea level) and a summary of basic statistics and trends of climatic elements in the area. Furthermore, a catalogue of circulation types was created for the period from August 2007 to July 2011, and finally, the relationships between individual circulation types and manifestations of climate elements (air temperature, precipitation and global radiation). The results of this thesis may be used to identify the types connected with bursts of glacial...
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Les tempêtes en France et dans les îles Britanniques : des aléas aux événements / Windstorms in France and in the British Isles : from weather hazards to weather and social eventsSchoenenwald, Nicolas 05 March 2013 (has links)
Bien qu'appartenant à la zone « tempérée », la France et les îles Britanniques connaissent pourtant de nombreux excès climatiques. Parmi ceux-ci, les tempêtes hivernales font partie des aléas les plus destructeurs, en même temps qu'elles assurent un transfert d'énergie thermique de la zone tropicale vers les plus hautes latitudes. Pour mieux comprendre la climatologie de ce météore, une chronologie des tempêtes a été établie à partir des cartes des bulletins météorologiques quotidiens disponibles depuis la fin de l'année 1864. Plus de 2400 cas ont été identifiés, ce qui a permis d'évaluer la variabilité interannuelle et intra-annuelle de l'aléa. Les données de pression recueillies sur les cartes et leur analyse mettent en évidence le creusement des tempêtes au cours de la période. Les directions de vent figurées sur les cartes ont par ailleurs permis de réaliser des roses des vents pour une série de stations irlandaises, britanniques et françaises. La cartographie des minima de pression permet de faire apparaître des trajectoires privilégiées. L'étude climatologique s'achève par la recherche d'une cyclicité des tempêtes et par l'étude de leur lien avec l'ONA. Ce travail s'intéresse ensuite aux tempêtes qui ont fait événement pour les météorologues et/ou pour l'ensemble de la société du pays concerné. Ainsi sont mises en lumière les étapes de la compréhension de la météorologie des tempêtes. D'autre part, les tempêtes-événements retenues illustrent des évolutions économiques et sociales ainsi que les changements de gestion du risque tempête. Elles montrent aussi comment la culture du risque tempête s'est forgée et comment la mémoire du risque a parfois été réactivée. / Through France and the British Isles belong to the « temperate » zone, they both experience a lot of weather hazards. Among those hazards, winter storms are some of the most destructive ones, but in the same time they contribute to the thermal energy transfer from the tropical zone to the mid-latitudes. As a result, they play a major role in the world's thermal balance. In order to better understand the climatology of these meteors, a storm chronology has been established from the daily weather maps that are available since the end of 1864. More than 2400 cases have been identified which has allowed to measure the year-to-year and seasonal variability. Pressure data collected from the maps and their analysis show a deepening trend of their core pressures over the period. Wind directions displayed on the maps for different weather stations have been used to generate wind roses for a selection of Irish, British and French weather stations. The climatological study ends up in the calculation of the periodicity of storms as well as their link with the NAO. This study focuses then on a few storms that have been considered has events, either for the meteorologists or for the entire population of the country hit by the storm. Thus is highlighted the different stages of the meteorological understanding of wind storms in Europe. Moreover, the selected storms as social events underline economic and social evolutions as well as changes in the risk management of storms. These storms also show how a risk culture has emerged and how the risk memory has been re-activated.
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Modelagem da irradiação direta na incidência normal em Botucatu: aprendizado de máquina, estatístico e linke / Modeling of direct irradiation at normal incidence in Botucatu: machine learning, statistical and linkeSantos, Cícero Manoel dos [UNESP] 04 March 2016 (has links)
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Previous issue date: 2016-03-04 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A irradiação direta na incidência normal (Hb) possui papel importante no manejo de culturas agrícolas, na utilização como fonte de energia renovável e na modelagem atmosférica. Apesar de sua importância em diferentes áreas, medidas pontuais de Hb não são facilmente disponíveis nos centros de pesquisas, devido ao elevado custo de exportação dos sensores e suas manutenções periódicas. Os modelos estatísticos têm sido desenvolvidos e utilizados para estimativa de Hb nos locais onde não são monitorados. Estes modelos, normalmente, utilizam a Hg como variável de entrada, pois é a variável mais comumente medida em estações solarimétricas. Os modelos estatísticos correlacionam à fração transmitida da irradiação direta na incidência normal (ktb) com transmissividade atmosférica (kt) ou com a razão de insolação (n/N). Recentemente as técnicas de Aprendizado de Máquinas foram inseridas para estimativa de Hb. Teoricamente, são técnicas que apresentam alto desempenho na estimativa de modelos e gerar valores estimados mais precisos de Hb que os modelos estatísticos. O trabalho está divido em 4 capítulos divididos da seguinte forma. Capítulo 1: Propor a utilização da técnica Máquina de Vetor de Suporte – SVM e da Redes Neurais Artificiais para estimativa de Hb e comparar com os modelos estatísticos, testando diferentes variáveis de entrada, . Capítulo 2: Comparar a SVM com os modelos estatísticos. Capítulo 3: Comparar Rede Neural Artificial – RNA com os modelos estatísticos, utilizando o algoritmo Backpropagation. Capítulo 4: Modelagem da turbidez atmosférica de Linke com Hb. A fração transmitida de Hb (ktb) é modelada para obter Hb. Para treinamento e validação dos modelos é utilizado um banco de dados de 13 anos (1996 – 2008), medidos na estação radiométrica localizada na Faculdade de Ciências Agronômicas – FCA/UNESP (22,85°S; 48,45°W e 786m). Foram testadas diferentes variáveis de entrada para verificar qual a melhor na estimava dos modelos. Os índices estatísticos: MBE, rMBE, RMSE, rRMSE, d de Willmott e o erro percentual (%) são utilizados para validar os modelos. Os modelos foram propostos e avaliados nas partições de tempo: horária e diária. Os resultados mostraram que os modelos estatísticos estimam Hb com resultados (20% ≤ rRMSE < 30%). Os modelos propostos (SVM e RNA) geram resultados melhores que os modelos estatísticos e são indicados para estimativa de Hb (rRMSE < 20%). O modelo da SVM estima Hb melhor que RNA, por isso seu uso é tido como a primeira escolha entre os modelos. / The direct irradiation at normal incidence (Hb) is an important role in the management of crops, in the use as a renewable energy source and atmospheric modeling. Despite its importance in different areas, specific measures Hb are not readily available in research centers, due to the high cost of exporting the sensors and periodic maintenance of the sensors. Statistical models have been developed and used to estimate Hb in places where they are not monitored. These models usually use the Hg as input variable, as is the variable most commonly measured in solarimetric stations. Statistical models correlate to the fraction transmitted at Hb (ktb) with atmospheric transmissivity (kt) or insolation ratio (n/N). Recently the Machine Learning techniques (ML) were inserted for estimation of Hb. Theoretically, these techniques have greater capacity to model and generate more precise values of Hb that statistical models. The work is divided into four chapters divided as follows. Chapter 1: To propose the use of Support Vector Machine (SVM) and Artificial Neural Networks (ANN) technical to estimate Hb and compare the statistical models, testing different input variables. Chapter 2: To compare the SVM with the statistical models. Chapter 3: To compare Artificial Neural Network ANN) with statistical models using the backpropagation algorithm. Chapter 4: Modeling of atmospheric turbidity Linke with Hb. The ktb is modeled for get indirectly Hb. The validation methodology of the models with typical and atypical year is adopted and evaluated. It used a database of 13 years data (1996-2008), measured in radiometric station located at the Faculty of Agricultural Sciences - FCA/UNESP (22.85° S, 48.45° W and 786m. Different input variables are tested in the models to see if the estimate is improving. The variables used are: Hb, Hg, solar insolation (n), air temperature and relative humidity the other variables were obtained by mathematical equations. Statistical indices: MBE, rMBE, RMSE, rRMSE, d Willmontt and percent error (%) are used to validate the models. The models are proposed and evaluated in time: hourly and daily partitions. The results show that the statistical models estimate Hb with acceptable results (rRMSE ≤ 20% <30%). The proposed models (SVM and ANN) generate better results than the statistical models and are suitable for estimation of Hb (rRMSE <20%). The model of SVM estimates Hb better than ANN, so its use is considered the first choice among the models. / CNPq: 140104/2013-5
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GERAÇÃO DA BASE CLIMÁTICA DE SANTA MARIA -RS- PARA ANÁLISE DE DESEMPENHO TÉRMICO E EFICIÊNCIA ENERGÉTICA DE EDIFICAÇÕES / GENERATION OF THE CLIMATE BASE OF SANTA MARIA -RS- FOR ANALYSIS OF THERMAL PERFORMANCE AND ENERGY EFFICIENCY OF BUILDINGSFlores, Michelle Gomes 17 July 2014 (has links)
The treatment and the availability of climatological data are essential to the buildings
bioclimatic design. Energy efficiency can only be achieved when the plan considers local
weather specificities. This study contributes with the subject through the systematization of
climate data for the region of Santa Maria, RS. The data were collected to generate the Test
Reference Year (TRY), the Typical Meteorological Year (TMY), the bioclimatic chart (via
Analysis Bio and Psychros software), weather files compatible with programs such as
EnergyPlus and Design Builder, the diagram of winds (wind rose) elaborated by the software
Analysis SOL-AR and the typical day of project. Some of these systematizations already
existed but they were related to a lower period of years. The study inputted hourly data of
twelve years (2002 to 2013) and updated the data treatment methods. The files generation was
based in a scientific bibliography and methodologies that have been employed by research
groups concerned with the issue, such as works developed by Duffie and Beckmann (1980),
Goulart (1993), Pereira (2004), Carlo and Lamberts (2005) and Roriz (2012). The results were
conformed in a language accessible to designers and other agents in order to promote its
effective use for better energy efficiency and comfort of building users in Santa Maria s
region. Is was obtained 28,5% of comfort and 71,5% of discomfort. The ventilation is the
main strategy for the summer, with 18,4%. For the cold, the solar heating, with 29,4%, is the
best percentage. In relation to the summer winds direction, the predominant orientation is
east. Therewith, the major importance of this research is in the knowledge of bioclimatic
guidelines that help architects and engineers in architectonic propositions adjusted to the
clime, besides the availability of climate files for thermo-energetic simulation. / O tratamento e a disponibilização de dados climáticos para o projeto bioclimático de
edificações são fundamentais. A eficiência energética só pode ser atingida quando o projeto
considera as especificidades do clima local. Este estudo contribui com o assunto através da
sistematização de dados climáticos para a região de Santa Maria, RS. Os dados foram tratados
de forma a gerar o Ano Climático de Referência (TRY) e o Ano Meteorológico Típico
(TMY), a carta bioclimática (através dos programas Analysis Bio e Psychros), arquivos
climáticos compatíveis com programas como o EnergyPlus e Design Builder, o diagrama de
ventos (rosa dos ventos) elaborado pelo software Analysis SOL-AR e o dia de projeto típico.
Algumas dessas sistematizações já existiam, porém em um período de anos inferior. O estudo
incorporou dados horários de doze anos (2002 a 2013) e atualizou os métodos de tratamento
de dados. A geração dos arquivos baseou-se em bibliografia científica e metodologias que
vêm sendo empregadas por grupos de pesquisa envolvidos no tema, como em trabalhos
desenvolvidos por Duffie e Beckmann (1980), Goulart (1993), Pereira (2004), Carlo e
Lamberts (2005) e Roriz (2012). Os resultados foram conformados em uma linguagem
acessível aos projetistas e outros agentes a fim de promover seu efetivo uso na melhor
eficiência energética e conforto dos usuários de edificação da região de Santa Maria. Obtevese
28,5% de conforto e 71,5% de desconforto. A ventilação é a principal estratégia para verão,
com 18,4%. Para o frio, o aquecimento solar, com 29,4%, é a maior porcentagem. Em relação
à direção de ventos de verão, a orientação predominante é o leste. Com isso, a grande
importância dessa pesquisa está no conhecimento de diretrizes bioclimáticas para auxiliar os
arquitetos e engenheiros em suas propostas arquitetônicas adequadas ao clima, além da
disponibilidade de arquivos climáticos para simulação energética.
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Mixed Layer Thermodynamics Of The Southeastern Arabian Sea Using ARMEX ObservationsParampil, Sindu Raj 11 1900 (has links) (PDF)
No description available.
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Streamflow Forecasting for Blacksmith For River, UtahFok, Yu-Si 01 May 1959 (has links)
PURPOSE:
The method for streamflow forecasting by using Fourier Series and Multiple Regression as a mathematical model have been suggested and proved with high accuracy for the streamflow forecasting on Logan River, Utah by Professor Cleve H. Milligan and Dr. Rex L. Hurst.
In this thesis the method is extended to the forecasting for the Blacksmith Fork River, south of the Logan River.
Because the climatological data are not available in the Blacksmith Fork watershed, this thesis also provides a technique for using the available data from adjacent watersheds.
OBJECTIVES:
1. To forecast the streamflow on Blacksmith Fork River, Cache County, Utah by using Fourier Series and Multiple Regression as a mathematical model.
2. To test the consistency of the snow, temperature, precipitation, and streamflow data by statistical methods.
3. To test the significance of the variables considered in the mathematical model.
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