Search for dissertations about: "Sven Halldin"

Showing result 11 - 15 of 16 swedish dissertations containing the words Sven Halldin.

  2. 11. Evaporation and Heat-flux Aggregation in Heterogeneous Boreal Landscapes

    Author : Tony Persson; Sven Halldin; Dimitris Melas; Deliang Chen; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Hydrology; land-surface processes; heterogeneity; surface fluxes; soil-water content; high latitudes; snow; lakes; climate; mesoscale model; NOPEX; WINTEX; Hydrologi; Hydrology; Hydrologi;

    Abstract : The boreal forests represent 8 % of all forested areas on the earth and have a significant role in the control of greenhouse gases and an impact on global climate change. The main objective of this thesis is to increase the understanding of how evaporation and heat-flux processes in the boreal forest zone are affecting the regional and global climate. READ MORE

  4. 12. Hydro-Climatic Variability and Change in Central America : Supporting Risk Reduction Through Improved Analyses and Data

    Author : Beatriz Quesada-Montano; Sven Halldin; Hugo G. Hidalgo; Ida K. Westerberg; Fredrik Wetterhall; Denis Hughes; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Central America; climate variability; disaster risk reduction; droughts; drought indices; floods; hydrological model; process constraints; statistical downscaling; uncertainty; ungauged basins; water resources.; Hydrology; Hydrologi;

    Abstract : Floods and droughts are frequent in Central America and cause large social, economic and environmental impacts. A crucial step in disaster risk reduction is to have a good understanding of the causing mechanisms of extreme events and their spatio-temporal characteristics. READ MORE

  5. 13. Flood Prediction in data-scarce basins : Maximising the value of limited hydro-meteorological data

    Author : José Eduardo Reynolds Puga; Sven Halldin; Chong-Yu Xu; Jan Seibert; Thomas J. Grabs; Vazken Andréassian; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Floods; data scarcity; value of information; rainfall-runoff modelling; regionalisation; rainfall-forecasts; event-based calibration; climatological day; discharge day; temporal resolution; modelling time-step.; Databrist; flödestoppsbaserad kalibrering; högflöde; informationsvärde; klimatologiskt dygn; nederbörds-avrinningsmodell; modelltidssteg; regionalisering; regnprognos; tids-upplösning; vattenföringsdygn; översvämning.; Inundaciones; falta de datos; valor de información; modelos lluvia escorrentía; regionalización; pronósticos de lluvia; definición del día; resolución temporal; paso de tiempo.;

    Abstract : Floods pose a threat to society that can cause large socio-economic damages and loss of life in many parts of the world. Flood-forecasting models are required to provide simulations at temporal resolutions higher than a day in basins with concentration times smaller than 24 h. READ MORE

  6. 14. Observational Uncertainties in Water-Resources Modelling in Central America : Methods for Uncertainty Estimation and Model Evaluation

    Author : Ida Westerberg; Sven Halldin; Jan Seibert; Lars-Christer Lundin; Chong-Yu Xu; Deliang Chen; Alberto Montanari; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Central America; Discharge; Flow-duration curve; Fuzzy regression; GLUE; Model evaluation; Non-stationarity; Observational uncertainty; Precipitation; Quality control; Rating curve; Regionalisation; Uncertainty estimation; Ungauged basins; Water resources; Avbördningskurva; Centralamerika; GLUE; icke-stationaritet; kvalitetskontroll; modellutvärdering; nederbörd; observationsosäkerheter; avrinningsområden utan vattenfö-ringsdata; oskarp regression; osäkerhetsuppskattning; regionalisering; varaktighetskurva; vattenföring; vattenresurser; Hydrology; Hydrologi; Hydrology; Hydrologi;

    Abstract : Knowledge about spatial and temporal variability of hydrological processes is central for sustainable water-resources management, and such knowledge is created from observational data. Hydrologic models are necessary for prediction for time periods and areas lacking data, but are affected by observational uncertainties. READ MORE

  7. 15. Statistical Downscaling of Precipitation from Large-scale Atmospheric Circulation : Comparison of Methods and Climate Regions

    Author : Fredrik Wetterhall; Sven Halldin; Chong-Yu Xu; Lars-Christer Lundin; Deliang Chen; Hans von Storch; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Hydrology; Statistical; Downscaling; Precipitation; Large-scale circulation; PCA; TWS; Weather pattern; Regression; Weather generator; Hydrologi; Hydrology; Hydrologi;

    Abstract : A global climate change may have large impacts on water resources on regional and global scales. General circulation models (GCMs) are the most used tools to evaluate climate-change scenarios on a global scale. They are, however, insufficiently describing the effects at the local scale. READ MORE