Sökning: "ice core"

Visar resultat 6 - 10 av 57 avhandlingar innehållade orden ice core.

1. 6. Sulfur in polar ice and snow : Interpretations of past atmosphere and climate through glacial archives

   Författare :Ulf Jonsell; Margareta Hansson; Mark Curran; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ice cores; aerosols; sulfate; methanesulfonate; sulfur isotopes; climate; glacial cycles; Antarctica; Greenland; Physical geography; Naturgeografi;

   Sammanfattning : Snow contains information on the atmosphere it is deposited from. This information is stored in polar ice sheets (Antarctica and Greenland), which are unique geochronological archives of past climate and atmospheric composition. On time scales from annual to glacial cycles, this thesis deals with the signals of sulfur compounds in these archives. LÄS MER

3. 7. Planetary Timemaking : Paleoclimatology and the Temporalities of Environmental Knowledge, 1945-1990

   Författare :Erik Isberg; Sverker Sörlin; Sabine Höhler; Adam Wickberg; Etienne Benson; KTH; []
   Nyckelord :HUMANIORA; HUMANITIES; HUMANIORA; HUMANITIES; NATURVETENSKAP; NATURAL SCIENCES; paleoclimatology; environmental history; temporality; ice core; deep-sea core; North Atlantic; timemaking; theory of history; planetary-scale environmental knowledge; paleoklimatologi; miljöhistoria; temporalitet; iskärna; borrkärna; Nordatlanten; tidsskapande; historieteori; planetär miljökunskap; History of Science; Technology and Environment; Historiska studier av teknik; vetenskap och miljö;

   Sammanfattning : This thesis concerns the history of paleoclimatology in the postwar period. It follows the trajectory of two climate proxy records – ice cores and deep-sea cores – in the North Atlantic region, from their emergence as scientific objects in the 1940s to their incorporation into Earth System Science in the 1980s. LÄS MER

4. 8. Local Structure of Hydrogen-Bonded Liquids

   Författare :Matteo Cavalleri; Lars G.M. Pettersson; John Tse; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; hydrogen-bond; water; ice; density functional theory; DFT; core-level spectroscopies; x-ray absorption; Physical chemistry; Fysikalisk kemi;

   Sammanfattning : Ordinary yet unique, water is the substance on which life is based. Water seems, at first sight, to be a very simple molecule, consisting of two hydrogen atoms attached to one oxygen. LÄS MER

5. 9. Tensile fracture of ice : test methods and fracture mechanics analysis

   Författare :Lars Stehn; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Structural Engineering; Konstruktionsteknik;

   Sammanfattning : This thesis is concerned with several aspects of fracture of both brackish (low salinity) sea ice and freshwater ice. The tests and analyses are confined to tensile, or in fracture mechanics language, Mode I, fracture. LÄS MER

7. 10. Solar variability over the Holocene period : disentangling geomagnetic and solar influences on a new continuous 10Be record from Little Dome C, Antarctica

   Författare :Hoang Long Nguyen; MERGE: ModElling the Regional and Global Earth system; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ice core; cosmogenic radionuclide; 10Be; 14C; solar activity; paleomagnetism; ; Holocene;

   Sammanfattning : Reliable information on solar activity over the Holocene period is important to predict the Sun in the future and to understand the mechanism behind the Sun-climate linkage. Presently, there are discrepancies in the proxy data of solar activity due to reasons that are not yet understood. LÄS MER