Search for dissertations about: "northern high latitudes"

Showing result 6 - 10 of 46 swedish dissertations containing the words northern high latitudes.

  2. 6. Magnetic orientation in migratory birds

    Author : Rachel Muheim; Funktionell zoologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Animal ecology; Djurekologi; cue-conflict; clock-shift; cue calibration; geomagnetic field; high Arctic latitudes; Emlen funnel; magnetic compass; magnetoreception; navigation; migration; bird; orientation;

    Abstract : My thesis focuses on magnetic orientation in migratory birds, i.e. how they can perceive information from the Earth’s magnetic field and use it for orientation. READ MORE

  4. 7. Emission of methane from northern lakes and ponds

    Author : Martin Wik; Patrick Crill; Isabelle Laurion; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; lakes; ponds; water bodies; methane; fluxes; ebullition; stable isotopes; arctic; subarctic; carbon cycling; climate change; geokemi; Geochemistry;

    Abstract : Northern lakes and ponds are abundant and emit large amounts of the potent climate forcer methane to the atmosphere at rates prone to change with amplified Arctic warming. In spite of being important, fluxes from surface waters are not well understood. READ MORE

  5. 8. Holocene climate and environmental change in high latitudes as recorded by stable isotopes in peat deposits

    Author : Päivi Kaislahti Tillman; Steffen Holzkämper; Stefan Wastegård; Peter Kuhry; Thomas W. D. Edwards; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; stable isotopes; Holocene; subarctic; climate; Sphagnum fuscum; kvartärgeologi; Quarternary Geology;

    Abstract : In this thesis, stable carbon and oxygen isotopes in α-cellulose isolated from Sphagnum fuscum moss remains were used as climate proxies. The main focus was to implement the methods in records from high latitude peatlands in the Northern Hemisphere (west-central Canada and north-eastern European Russia), reconstruct palaeoclimate of the studied regions during the Holocene, and evaluate the compatibility of results with other proxy records, especially tree-ring isotope time-series. READ MORE

  6. 9. Investigation of Polar Mesosphere Summer Echoes in Northern Scandinavia

    Author : Victoria Barabash; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; Polar Mesosphere Summer Echoes; middle atmospheric dynamics; ionospheric disturbances; solar radiation; aerosol; MST radar; planetary waves; noctilucent clouds; Fysik; Physics; Fysik; rymdfysik; Space Physics;

    Abstract : This PhD thesis deals with phenomena which are closely related to the unique thermal structure of the polar summer mesosphere, namely Polar Mesosphere Summer Echoes (PMSE). PMSE are strong radar echoes commonly observed by VHF MST radars from thin layers in the 80-90 km altitude interval at high latitudes during summer. READ MORE

  7. 10. Phytoplankton response to a changing climate in lakes in northern Sweden

    Author : Jennie Sandström; Nils Ekelund; Hugo von Zeipel; Mittuniversitetet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Climate change; cyanobacteria; ice break-up; oligotrophic lakes; phytoplankton; temperature;

    Abstract : In a climate change perspective, increased air temperatures are already a reality and are expected to increase even more in the future, especially in areas at high latitudes. The present thesis therefore addresses the influence of climate change on the physical properties and the phytoplankton communities of typical small and oligotrophic lakes in northern Sweden (62-64˚N). READ MORE