Sökning: "Arctic Atmosphere"

Visar resultat 1 - 5 av 80 avhandlingar innehållade orden Arctic Atmosphere.

1. 1. The Arctic Atmosphere : Interactions between clouds, boundary-layer turbulence and large-scale circulation

   Författare :Georgia Sotiropoulou; Michael Tjernström; Joseph Sedlar; Susanne Crewell; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arctic; mixed-phase clouds; thermodynamic structure; Arctic inversion; cloud-surface interactions; seasonal transition; IFS model; LES; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

   Sammanfattning : Arctic climate is changing fast, but weather forecast and climate models have serious deficiencies in representing the Arctic atmosphere, because of the special conditions that occur in this region. The cold ice surface and the advection of warm air aloft from the south result in a semi-continuous presence of a temperature inversion, known as the “Arctic inversion”, which is governed by interacting large-scale and local processes, such as surface fluxes and cloud formation. LÄS MER

3. 2. The Arctic Summer Atmosphere

   Författare :Cecilia Wesslén; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arctic; meteorology; reanalysis; clouds; remote sensing;

   Sammanfattning : The Arctic climate has experienced large changes over recent decades, the largest for any region on Earth. To understand the underlying reasons for this climate sensitivity, we need both models and observations. LÄS MER

4. 3. Properties and Origin of Arctic Aerosols

   Författare :Ann-Christine Engvall; Jörg Gumbel; Frode Stordal; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arctic aerosols; Arctic troposphere; air-mass transport; Atmosphere and hydrosphere sciences; Atmosfärs- och hydrosfärsvetenskap; atmosfärvetenskap; Atmospheric Sciences;

   Sammanfattning : The present thesis deals with the origin and physics of aerosols in the Arctic atmosphere. These show a large annual variability due to changes of the photochemical and cloud processes as well as of the synoptic-scale atmospheric pressure patterns. LÄS MER

5. 4. The high Arctic summer aerosol : Size, chemical composition, morphology and evolution over the pack-ice

   Författare :Evelyne Hamacher-Barth; Caroline Leck; Stephan Weinbruch; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arctic; aerosol; marine gel; electron microscopy; EDX-spectroscopy; chemical composition; morphology; size distribution; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

   Sammanfattning : Aerosol particles, especially in the high Arctic are still not very well represented in climate models. Particle size and number concentrations are strongly under-predicted and temporal variations of aerosol composition and size are still not very well understood, mainly due to the sparsity of observations. LÄS MER

7. 5. A large-eddy simulation perspective on Arctic airmass transformation and low-level cloud evolution

   Författare :Antonios Dimitrelos; Annica Ekman; Caballero Rodrigo; Rune Grand Graversen; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Arctic; mixed phase clouds; sea ice; Arctic amplification; atmospheric energy transport; CCN; Atmospheric Sciences and Oceanography; atmosfärvetenskap och oceanografi;

   Sammanfattning : The Arctic is currently warming faster than other regions of the Earth. Many processes and feedbacks contribute to the enhanced warming. Among these are the radiative effects of clouds. LÄS MER