Sökning: "Atlantic layer"
Visar resultat 1 - 5 av 8 avhandlingar innehållade orden Atlantic layer.
1. Flow preferences of upstream migrating Atlantic salmon (Salmo salar)
Sammanfattning : On their way from the sea to their spawning grounds in rivers, Atlantic salmon are often delayed or hindered by dams or other obstructions. Building a fishway can save a population that would otherwise go extinct. LÄS MER
2. The Ups and Downs of the Holocene: Exploring Relationships between Global CO2 and Climate Variability in the North Atlantic Region
Sammanfattning : This thesis aimed to examine the relationship between climate and atmospheric CO2 concentrations through rapid climate changes during the Holocene. Climate was reconstructed using high-resolution, radiocarbon dated, lake sediment geochemical proxies (magnetic susceptibility, loss-on-ignition, total carbon/nitrogen/sulphur determinations and biogenic silica), vegetational reconstruction (pollen analysis) and stomatal frequency based CO2 reconstructions. LÄS MER
3. Towards a Holocene tephrochronology for the Azores
Sammanfattning : The Azores is situated in the North Atlantic Ocean and is one of the most active volcanicregions in the Northern Hemisphere. The volcanic history of the islands is fairly wellknown and several explosive trachytic eruptions have been reported but the geochemicalcompositions of the glass component of the tephra as well as the dispersal oftephras to distal areas are less well known. LÄS MER
4. Anthropogenic Radionuclides in the Arctic Ocean: Distribution and Pathways
Sammanfattning : Anthropogenic radionuclide concentrations have been determined in seawater and sediment samples collected in 1991, 1994 and 1996 in the Eurasian Arctic shelf and interior. Global fallout, releases from European reprocessing plants and the Chernobyl accident are identified as the three main sources. LÄS MER
5. Aerosol impacts on subtropical low-level clouds: a satellite and modelling perspective
Sammanfattning : Complex interactions between aerosols, clouds, and radiation impact Earth's climate. However, several aspects of these interactions remain uncertain, which has led to extensive research over the last decades. LÄS MER