Sökning: "Forcing"

Visar resultat 6 - 10 av 261 avhandlingar innehållade ordet Forcing.

  1. 6. Effects of coastal forcing on turbulence and boundary-layer structure

    Författare :Linda Ström; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Geovetenskap; Earth sciences; Geovetenskap; Meteorology; meteorologi;

    Sammanfattning : Coastal mountains of significant elevation impose constraints for the surrounding flow. The aim of this study is to describe the modifications of the marine atmospheric boundary layer that occur offshore of the west coast of the United States. Aircraft measurements, up to 1000 km off the coast from two experiments, are used. LÄS MER

  3. 7. Historical anthropogenic radiative forcing of changes in biogenic secondary organic aerosol

    Författare :Juan Camilo Acosta Navarro; Ilona Riipinen; Annica Ekman; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Human activities have lead to changes in the energy balance of the Earth and the global climate. Changes in atmospheric aerosols are the second largest contributor to climate change after greenhouse gases since 1750 A.D. LÄS MER

  4. 8. Volcanic Aerosols in the Upper Troposphere and Stratosphere – Aircraft- and Satellite-Based Observations

    Författare :Sandra Andersson; Kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; carbonaceous aerosol; sulphate; ash; volcanic particles; upper troposphere; lowermost stratosphere; Stratospheric aerosol; volcanism; aerosol optical depth; radiative forcing; Fysicumarkivet A:2015:Andersson;

    Sammanfattning : Volcanic eruptions are the largest source of variability in the stratospheric particle concentration as they inject SO2 that is subsequently converted into sulphate particles. No major perturbation of the stratospheric aerosol load has been observed since the large eruption of Pinatubo in 1991, but several moderate eruptions after 2000 have caused deviations from stratospheric background conditions. LÄS MER

  5. 9. Global stability analysis of three-dimensional boundary layer flows

    Författare :Mattias Brynjell-Rahkola; Dan Henningson; Philipp Schlatter; Ardeshir Hanifi; Spencer Sherwin; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hydrodynamic stability; transition to turbulence; global analysis; boundary layers; roughness; laminar flow control; Stokes Laplace preconditioner; optimal forcing; crossflow vortices; Ginzburg-Landau; Falkner-Skan-Cooke; Blasius; lid-driven cavity;

    Sammanfattning : This thesis considers the stability and transition of incompressible boundary layers. In particular, the Falkner–Skan–Cooke boundary layer subject to a cylindrical surface roughness, and the Blasius boundary layer with applied localized suction are investigated. LÄS MER

  7. 10. Studies of Volcanic Influence on Aerosols, Clouds and Climate

    Författare :Johan Friberg; Ergonomi och aerosolteknologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lowermost stratosphere; volcanic aerosol; upper troposphere; sulfurous aerosol; carbonaceous aerosol; ion beam analysis; volcanism; indirect effect; radiative forcing; direct effect; Stratosphere; Fysicumarkivet A:2016:Friberg;

    Sammanfattning : This thesis focuses on the influence of volcanism on the compositions of the aerosols in the upper troposphere (UT) and lowermost stratosphere (LMS), and their direct and indirect impact on climate. Aerosol data were obtained by aircraft-borne sampling, using the CARIBIC (Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container) platform, and laboratory-based ion beam analysis of aerosol samples at the Lund Ion Beam Analysis Facility (LIBAF). LÄS MER