Sökning: "The atmospheric boundary layer"

Visar resultat 1 - 5 av 65 avhandlingar innehållade orden The atmospheric boundary layer.

1. 1. On the Arctic Boundary Layer : From Turbulence to Climate

   Författare :Thorsten Mauritsen; Gunilla Svensson; Joao Teixeira; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atmospheric boundary layers; Turbulence; Stable stratification; Gravity waves; Mesoscale motion; Arctic climate; Meteorology; Meteorologi; atmosfärvetenskap; Atmospheric Sciences;

   Sammanfattning : The boundary layer is the part of the atmosphere that is in direct contact with the ground via turbulent motion. At mid-latitudes the boundary layer is usually one or a few kilometers deep, while in the Arctic it is much more shallow, typically a few hundred meters or less. LÄS MER

3. 2. The Representation of Atmospheric Boundary Layer Processes in Global Climate Models

   Författare :Jenny Lindvall; Gunilla Svensson; Rodrigo Caballero; Andrew R. Brown; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; The atmospheric boundary layer; Global climate models; Diurnal cycle; Flux towers; Diurnal temperature range; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

   Sammanfattning : The atmospheric boundary layer is the lowest part of the atmosphere, which is in direct contact with the surface. It is here, in this turbulent layer, that the exchange of heat, moisture and momentum between the surface and the atmosphere takes place. LÄS MER

4. 3. 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

5. 4. Arctic Atmospheric Rivers : Eulerian and Lagrangian features, and trends over the last 40 years

   Författare :Cheng You; Michael Tjernström; Abhay Devasthale; Heikki Järvinen; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arctic; Atmospheric river; Stratocumulus; Blocking; Turbulence; Longwave irradiance; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

   Sammanfattning : Arctic Atmospheric rivers, termed ‘warm-and-moist intrusion’ (WaMAI) in this thesis, transporting heat and moisture into the Arctic from lower latitudes, is a key contributor to the amplified warming in the Arctic under global change (Arctic Amplification). However, the warming effect of WaMAIs and its transformation along the trajectories into high Arctic still remain unclear, as well as their relation with the large-scale atmospheric circulation. LÄS MER

7. 5. Fluxes and Mixing Processes in the Marine Atmospheric Boundary Layer

   Författare :Erik Olof Nilsson; Anna Rutgersson; Harm Jonker; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Waves; Growing sea; Swell; Marine boundary layer; Air-sea interaction; Mixing; Momentum flux; Wind stress; Flux attenuation; Sensor separation; Large eddy simulation; Multiresolution analysis; Coupling; Wave model; Climate model; Wave age; Meteorology; Meteorologi;

   Sammanfattning : Atmospheric models are strongly dependent on the turbulent exchange of momentum, sensible heat and moisture (latent heat) at the surface. Oceans cover about 70% of the Earth’s surface and understanding the processes that control air-sea exchange is of great importance in order to predict weather and climate. LÄS MER