Sökning: "atmospheric sources"

Visar resultat 1 - 5 av 164 avhandlingar innehållade orden atmospheric sources.

  1. 1. Ultra-short-chain perfluoroalkyl acids : Environmental occurrence, sources and distribution

    Författare :Maria Björnsdotter; Ingrid Ericson Jogsten; Anna Kärrman; Leo W. Y. Yeung; Tom Harner; Örebro universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; PFASs; TFA; TFMS; point sources; precursors; solar radiation; atmospheric oxidation; atmospheric deposition; flux; Arctic;

    Sammanfattning : Ultra-short-chain perfluoroalkyl acids (PFAAs) is a group of highly fluorinated and very stable chemicals. Their small molecular structure in combination with the acidic functional group result in highly polar compounds and concern has been raised as these substances may threaten our drinking water supplies. LÄS MER

  2. 2. Chemical characteristics of atmospheric aerosols : the influence of natural and man-made sources and sinks

    Författare :Michael Norman; Jost Heintzenberg; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Meteorology; Meteorologi; meteorologi; Meteorology;

    Sammanfattning : In order to improve the understanding of the climatic and environmental effects of atmospheric aerosol particles, knowledge about their sources, sinks, chemical and physical characteristics as well as transportation in the atmosphere is needed. This thesis examines the water-soluble chemical characteristics of aerosol particles and precipitation and their interaction with trace gases. LÄS MER

  3. 3. On Sahelian-Sudan rainfall and its moisture sources

    Författare :Abubakr A. M. Salih; Qiong Zhang; Michael Tjernström; Alessandra Giannini; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Sudan; Sahel; rainfall; land use; deforestation; moisture sources; moisture transport; Lagrangian; moisture tagging; regional model; climate modeling; Atmospheric Sciences and Oceanography; atmosfärvetenskap och oceanografi;

    Sammanfattning : The African Sahel is one of the most vulnerable regions to climate variability at different time scales. It is an arid to semi-arid region with limited water resources. The summer rainfall is one of these sources, but it exhibits pronounced interannual variability. This thesis presents several aspects of Sahelian Sudan rainfall. LÄS MER

  4. 4. Sources, transport and fate of perfluoroalkyl acids in the atmosphere

    Författare :Jana Johansson; Ian Cousins; Tom Harner; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Perfluorinated alkyl acids; PFOS; PFOA; Isomers; Sources; Atmospheric transport; Sea spray; Gas-particle partitioning; Volatilisation; Applied Environmental Science; tillämpad miljövetenskap;

    Sammanfattning : Perfluoroalkyl acids (PFAAs) are man-made chemicals which have been observed in the global environment, even in locations far away from where they are emitted. These persistent substances are taken up in humans and biota and may have toxic effects. LÄS MER

  5. 5. Wind Turbine Sound Propagation in the Atmospheric Boundary Layer

    Författare :Olof Öhlund; Conny Larsson; Anna Sjöblom; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Wind turbine sound; atmospheric effects; outdoor sound propagation; refraction;

    Sammanfattning : Wind turbines have grown both in size and number in the past decades. The taller turbines has made it possible to place them in forest areas which is fortunate for a country like Sweden with lots of forest. An issue with wind turbines is the sound they produce. The sound mainly comes from the rotor blades when they pass through the air. LÄS MER