Sökning: "naturvetenskap geovetenskap och miljövetenskap miljövetenskap"
Visar resultat 11 - 15 av 2600 avhandlingar innehållade orden naturvetenskap geovetenskap och miljövetenskap miljövetenskap.
11. Exploring Strategies for the Combination of Multiple Space-geodetic Techniques
Sammanfattning : Space-geodetic techniques are based on signal acquisition from extraterrestrial radio sources that can be used to infer geodetic positioning and define Earth-fixed and inertial reference systems. These techniques, which include Very Long Baseline Interferometry (VLBI) and Global Navigation Satellite Systems (GNSS) among others, exhibit different strengths and weaknesses in recovering parameters of interest. LÄS MER
12. Diurnal variation of stratospheric short-lived species
Sammanfattning : Diurnal variation of stratospheric short-lived speciesMaryam KhosraviChalmers University of TechnologyDepartment of Earth and Space SciencesAbstractThe depletion of ozone in the stratosphere has a direct impact on the amount of ultravioletradiation reaching the Earth’s surface. The ozone abundance and distributionis controlled by the photo-chemical reactions and catalytic cycles involving halogens(chlorine and bromine), odd hydrogen and odd nitrogen species as well as by atmospherictransport. LÄS MER
13. Where have all the forests gone? Quantifying pantropical deforestation drivers
Sammanfattning : Deforestation across the tropics continues to be a major source of greenhouse gas emissions and the largest threat to biodiversity on land. With strengthened commitments to reduce deforestation from countries and companies alike, it is crucial that renewed investments for reducing deforestation be guided by a sound understanding of what drives deforestation. LÄS MER
14. Felling Forests from Afar: Quantifying Deforestation Driven by Agricultural Expansion and International Trade
Sammanfattning : Deforestation is a major source of human-caused greenhouse gas emissions and the largest threat to terrestrial biodiversity. Most forest loss is due to the expansion of agricultural land use increasingly driven by international demand for food, fuel and fibre. LÄS MER
15. Evasion of CO₂ from streams : quantifying a carbon component of the aquatic conduit in the boreal landscape
Sammanfattning : Lateral export of carbon (C) from soils to running waters is a persistent pathway for C with terrestrial origin. This "aquatic conduit" might be especially important in boreal regions where a significant part of the global C stock is stored in the soil. LÄS MER