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The Seasonal Variation of the Propagating Diurnal Tide in the Mesosphere and Lower Thermosphere. Part I: The Role of Gravity Waves and Planetary Waves
Publisher: American Meteorological Society
Abstract: The seasonal variation of the propagating diurnal tide in the mesosphere and lower thermosphere is examined using results from a 2-yr simulation of the extended version of the Canadian Middle Atmosphere Model (CMAM). The ...
The Seasonal Variation of the Propagating Diurnal Tide in the Mesosphere and Lower Thermosphere. Part II: The Role of Tidal Heating and Zonal Mean Winds
Publisher: American Meteorological Society
Abstract: A linear mechanistic tidal model is used to understand the mechanisms responsible for the seasonal variation of the propagating diurnal tide in the mesosphere and lower thermosphere simulated in the Canadian Middle Atmosphere ...
Consistent Scale Interaction of Gravity Waves in the Doppler Spread Parameterization
Publisher: American Meteorological Society
Abstract: The standard Doppler spread parameterization of gravity waves, which was proposed by C.-O. Hines and has been applied in a number of middle atmosphere general circulation models, is extended by the inclusion of all effects ...
Simulated Anthropogenic Changes in the Brewer–Dobson Circulation, Including Its Extension to High Latitudes
Publisher: American Meteorological Society
Abstract: Recent studies using comprehensive middle atmosphere models predict a strengthening of the Brewer?Dobson circulation in response to climate change. To gain confidence in the realism of this result it is important to quantify ...
Impact of Climate Change on Stratospheric Sudden Warmings as Simulated by the Canadian Middle Atmosphere Model
Publisher: American Meteorological Society
Abstract: The dynamics of Northern Hemisphere major midwinter stratospheric sudden warmings (SSWs) are examined using transient climate change simulations from the Canadian Middle Atmosphere Model (CMAM). The simulated SSWs show ...
A Robust Mechanism for Strengthening of the Brewer–Dobson Circulation in Response to Climate Change: Critical-Layer Control of Subtropical Wave Breaking
Publisher: American Meteorological Society
Abstract: limate models consistently predict a strengthened Brewer?Dobson circulation in response to greenhouse gas (GHG)-induced climate change. Although the predicted circulation changes are clearly the result of changes in ...
The GCM Response to Current Parameterizations of Nonorographic Gravity Wave Drag
Publisher: American Meteorological Society
Abstract: A comparison is undertaken of the response of a general circulation model (GCM) to the nonorographic gravity wave drag parameterizations of Hines, Warner and McIntyre, and Alexander and Dunkerton. The analysis is restricted ...
Is Missing Orographic Gravity Wave Drag near 60°S the Cause of the Stratospheric Zonal Wind Biases in Chemistry–Climate Models?
Publisher: American Meteorological Society
Abstract: early all chemistry?climate models (CCMs) have a systematic bias of a delayed springtime breakdown of the Southern Hemisphere (SH) stratospheric polar vortex, implying insufficient stratospheric wave drag. In this study ...
Dynamical Control of the Mesosphere by Orographic and Nonorographic Gravity Wave Drag during the Extended Northern Winters of 2006 and 2009
Publisher: American Meteorological Society
Abstract: version of the Canadian Middle Atmosphere Model (CMAM) that is nudged toward reanalysis data up to 1 hPa is used to examine the impacts of parameterized orographic and nonorographic gravity wave drag (OGWD and NGWD) on the ...
The Climate Impact of Past Changes in Halocarbons and CO2 in the Tropical UTLS Region
Publisher: American Meteorological Society
Abstract: chemistry?climate model coupled to an ocean model is used to compare the climate impact of past (1960?2010) changes in concentrations of halocarbons with those of CO2 in the tropical upper troposphere and lower stratosphere ...