Search for dissertations about: "Surface energy exchange"

Showing result 1 - 5 of 104 swedish dissertations containing the words Surface energy exchange.

2. 1. Land surface heat exchange over snow and frozen soil

   Author : David Gustafsson; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Surface energy balance; Snow; Boreal forest; SVAT models; Eddy-correlation Measurements; Latent heat flux; Sensible heat flux; Net radiation; Soil temperature; Aerodynamic roughness; Surface resistance; Civil engineering and architecture; Samhällsbyggnadsteknik och arkitektur;

   Abstract : The energy exchange in the soil-snow-vegetation-atmospheresystem was studied to improve the quantitative knowledge of thegoverning processes. The lack of such knowledge contributes tothe uncertainty in the applicability of many existing modelsindependent of the temporal or spatial scale. READ MORE

4. 2. Surface energy exchange and land-atmosphere interactions of Arctic and subarctic tundra ecosystems under climate change

   Author : Christian Stiegler; Institutionen för naturgeografi och ekosystemvetenskap; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Surface energy exchange; Arctic and subarctic tundra; climate change; permafrost; eddy covariance; snow cover; micrometeorology;

   Abstract : The surface energy balance determines the functioning of any ecosystem on the Earth but is still poorly understood in Arctic and subarctic biomes. In a dynamic system, such as the Earth’s climate, any change in its characteristics modifies the exchange of energy, water, and greenhouse gases between the surface and the atmosphere. READ MORE

5. 3. Surface Energy Exchange and Hydrology of a Poor Sphagnum Mire

   Author : Erik Kellner; Harald Grip; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Sphagnum; Geovetenskap; myr; energibudget; ytresistans; vitmossa; hydrologiska modeller; TDR; Earth sciences; Geovetenskap; Hydrology; hydrologi;

   Abstract : Mires surface energy and water budgets govern the conditions for climatic, hydrological, ecological and carbon balance processes. The components of the water and surface energy budgets were quantified over two growing seasons for an open boreal mire. READ MORE

6. 4. Nonlocal Correlations in Density Functional Theory

   Author : Henrik Rydberg; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; bonding; GGA; adhesion; graphene; DFT; exchange; adsorption; LDA; first principles; polarization; vdW; determinants; correlation; graphite; surface states; van der Waals; density-functional theory; physisorption; nonlocal; functional;

   Abstract : In Density Functional Theory, the widely used local and semilocal approximations to the exchange-correlation energy, the local density approximation (LDA) and the generalized gradient approximations (GGAs), lack a physical description of truly nonlocal correlation effects, which are absolutely essential for a proper description of soft matter. A scheme is proposed that provides a basis for systematic improvements beyond LDA and GGA, including correlations at intermediate and long range, giving rise to bonds of pure van der Waals type as well as more intricate, intermediate-range correlation bonds. READ MORE

7. 5. Electrode Degradation in Polymer Electrolyte Fuel Cells

   Author : Linnéa Strandberg; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Catalyst degradation; Platinum stability; Fuel cells;

   Abstract : To mitigate the climate crisis, and reduce carbon emissions from e.g. the transport and energy sectors, hydrogen has been proposed to be used as an environmentally friendly alternative energy carrier. READ MORE