Sökning: "cloud droplets"

Visar resultat 6 - 10 av 28 avhandlingar innehållade orden cloud droplets.

  1. 6. Modelling the effects of organic aerosol phase partitioning processes on cloud formation

    Författare :Samuel Joseph Lowe; Ilona Riipinen; Daniel Partridge; Harri Kokkola; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Cloud droplet activation; organic aerosol; cloud parcel modelling; Köhler theory; Sensitivity and Uncertainty analysis; Applied Environmental Science; tillämpad miljövetenskap;

    Sammanfattning : Atmospheric aerosols particles may act as cloud condensation nuclei (CCN) that provide sites for condensation of water vapour for the formation of cloud droplets, called cloud droplet activation. Whether aerosol particles are CCN is determined by their size, composition and the ambient humidity. LÄS MER

  3. 7. Experimental studies of ice particle formation with tropospheric relevance

    Författare :Erik Svensson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; heterogeneous nucleation; water; freezing; cloud droplets; levitation; electrodynamic balance; light scattering; oxalic acid; kaolinite; dinitrogen pentoxide;

    Sammanfattning : In their fourth assessment report, the Intergovernmental Panel on Climate Change points out the influence of particles suspended in air, known as an aerosol, as the main uncertainty in the understanding of the climate system. Aerosols affect climate in a number of ways. LÄS MER

  4. 8. Mixing and Evaporation at the Cloud Edge and Angular Dynamics of Small Crystals in Viscous Flow

    Författare :Johan Fries; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cloud microphysics; droplet evaporation; reactive flows; Jeffery orbits; shear flow;

    Sammanfattning : How liquid water in atmospheric clouds distributes over droplets of different sizes is important for the initiation of rainfall, and for the optical properties of the atmosphere. Droplet-number densities and droplet-size distributions change rapidly at turbulent cloud edges, where mixing of cloudy and dry air causes cloud dilution and droplet evaporation. LÄS MER

  5. 9. Modeling aerosol-cloud interactions in the Arctic

    Författare :Hannah Frostenberg; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Mixed-phase clouds; ice nucleating particles; heterogeneous freezing; Arctic; LES-modeling; parameterization;

    Sammanfattning : Clouds have a large impact on Earth’s energy balance, especially in the Arctic. Through their warming or cooling effect on the surface, clouds can play a critical role in the onset of melting and freezing of Arctic sea ice, which itself has a large effect on energy and moisture fluxes between the ocean and the atmosphere. LÄS MER

  7. 10. Aerosol-cloud interaction from an observational and modeling perspective

    Författare :Anders Engström; Annica Ekman; Heiner Körnich; Philip Stier; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

    Sammanfattning : Clouds may respond strongly to changes in the atmospheric aerosol population, and the response of clouds to an increased global aerosol burden could to some extent mask the warming caused by enhanced greenhouse gas concentrations. However, estimates of the impact of aerosols on cloud properties are associated with large uncertainties, both because of difficulties representing the aerosol-cloud interaction within models, and because of problems of unequivocally isolating the effect of aerosols on cloud properties in observational data. LÄS MER