Search Results
Special Sensor Microwave Imager/Sounder (SSMIS) on operational Defense Meteorological Satellite Program (DMSP) platforms. Additional details are provided in section 2b in Eckermann et al. (2016) . For estimating the planetary wave activity in the stratosphere and mesosphere, temperature and geopotential height from the MLS are analyzed ( Waters et al. 2006 ; Livesey et al. 2017 ). MLS covers Earth’s atmosphere from 82°S to 82°N on each sun-ynchronous sorbit and the data are analyzed between
Special Sensor Microwave Imager/Sounder (SSMIS) on operational Defense Meteorological Satellite Program (DMSP) platforms. Additional details are provided in section 2b in Eckermann et al. (2016) . For estimating the planetary wave activity in the stratosphere and mesosphere, temperature and geopotential height from the MLS are analyzed ( Waters et al. 2006 ; Livesey et al. 2017 ). MLS covers Earth’s atmosphere from 82°S to 82°N on each sun-ynchronous sorbit and the data are analyzed between
restriction is typically overcome through the use of analysis or reanalysis products, which provide an estimate of the state of the atmosphere based on assimilation of available heterogeneous observations using data assimilation systems (DASs). However, as depicted in Fig. 1b , the suite of NWP DASs used during DEEPWAVE all had upper boundaries that did not extend into the MLT. Indeed, at present, no NWP center provides either near-real-time or retrospective analysis products above 60–80-km altitude
restriction is typically overcome through the use of analysis or reanalysis products, which provide an estimate of the state of the atmosphere based on assimilation of available heterogeneous observations using data assimilation systems (DASs). However, as depicted in Fig. 1b , the suite of NWP DASs used during DEEPWAVE all had upper boundaries that did not extend into the MLT. Indeed, at present, no NWP center provides either near-real-time or retrospective analysis products above 60–80-km altitude
playing a more secondary role in the extratropical stratosphere. The focus of this study is the propagation and attenuation of gravity waves within the extratropical stratosphere. In the stratosphere, the important equator-to-pole Brewer–Dobson circulation is driven by momentum deposited in the extratropics by both planetary-scale Rossby waves and GWs (e.g., Holton et al. 1995 ). Within chemistry–climate models, planetary waves are resolved while the smaller-scale GWs and their GWD are largely
playing a more secondary role in the extratropical stratosphere. The focus of this study is the propagation and attenuation of gravity waves within the extratropical stratosphere. In the stratosphere, the important equator-to-pole Brewer–Dobson circulation is driven by momentum deposited in the extratropics by both planetary-scale Rossby waves and GWs (e.g., Holton et al. 1995 ). Within chemistry–climate models, planetary waves are resolved while the smaller-scale GWs and their GWD are largely
turbulence due to large GW amplitudes and superpositions; 6) energy, momentum, and tracer transports; 7) parameterizations of GW effects in large-scale (LS) models; and 8) GW influences on other processes such as convection, cloud microphysics, chemical reactions, and plasma dynamics and instabilities in the ionosphere. Many other papers have addressed important GW roles in oceans, lakes, other planetary atmospheres, and stellar interiors. PREVIOUS RESEARCH. The scope of GW dynamics and roles is
turbulence due to large GW amplitudes and superpositions; 6) energy, momentum, and tracer transports; 7) parameterizations of GW effects in large-scale (LS) models; and 8) GW influences on other processes such as convection, cloud microphysics, chemical reactions, and plasma dynamics and instabilities in the ionosphere. Many other papers have addressed important GW roles in oceans, lakes, other planetary atmospheres, and stellar interiors. PREVIOUS RESEARCH. The scope of GW dynamics and roles is
;2 . Holton , J. , and M. Alexander , 2000 : The role of waves in the transport circulation of the middle atmosphere . Atmospheric Science across the Stratopause , Geophys. Monogr. , Vol. 123, Amer. Geophys. Union, 21–35 . Hong , S.-Y. , and J.-O. Lim , 2006 : The WRF single-moment 6-class microphysics scheme (WSM6) . J. Korean Meteor. Soc. , 42 , 129 – 151 . Hu , X.-M. , J. Nielsen-Gammon , and F. Zhang , 2010 : Evaluation of three planetary boundary layer schemes in
;2 . Holton , J. , and M. Alexander , 2000 : The role of waves in the transport circulation of the middle atmosphere . Atmospheric Science across the Stratopause , Geophys. Monogr. , Vol. 123, Amer. Geophys. Union, 21–35 . Hong , S.-Y. , and J.-O. Lim , 2006 : The WRF single-moment 6-class microphysics scheme (WSM6) . J. Korean Meteor. Soc. , 42 , 129 – 151 . Hu , X.-M. , J. Nielsen-Gammon , and F. Zhang , 2010 : Evaluation of three planetary boundary layer schemes in
1. Introduction Gravity waves are ubiquitous features of the atmosphere. Although their major sources are tropospheric, some of these waves propagate into the stratosphere, mesosphere, and thermosphere where, in response to density decreases with height, amplitudes increase, leading to progressively larger impacts. Growth of amplitudes with height, for example, leads to wave breaking and deposition of energy and momentum into the flow as dynamical heating and body forcing, respectively
1. Introduction Gravity waves are ubiquitous features of the atmosphere. Although their major sources are tropospheric, some of these waves propagate into the stratosphere, mesosphere, and thermosphere where, in response to density decreases with height, amplitudes increase, leading to progressively larger impacts. Growth of amplitudes with height, for example, leads to wave breaking and deposition of energy and momentum into the flow as dynamical heating and body forcing, respectively
1. Introduction It is well known that gravity waves (GWs) flux horizontal momentum vertically in Earth’s atmosphere, depositing momentum wherever they attenuate (e.g., Bretherton 1969 ; McLandress 1998 ; Alexander et al. 2010 ). Mountain waves (MWs), GWs generated by flow over mountains, attain this momentum flux (MF) through a pressure drag interaction with the mountains that generate them ( Miles 1969 ; Smith 1979 ). That is, as the atmosphere flows over mountains, a pressure drag is
1. Introduction It is well known that gravity waves (GWs) flux horizontal momentum vertically in Earth’s atmosphere, depositing momentum wherever they attenuate (e.g., Bretherton 1969 ; McLandress 1998 ; Alexander et al. 2010 ). Mountain waves (MWs), GWs generated by flow over mountains, attain this momentum flux (MF) through a pressure drag interaction with the mountains that generate them ( Miles 1969 ; Smith 1979 ). That is, as the atmosphere flows over mountains, a pressure drag is
every 6 h. The outermost domain was allowed to spin up for 6 h before the inner domains were initialized. Physical parameterizations used were Thompson microphysics, YSU planetary boundary layer (PBL) physics, Kain–Fritsch cumulus (for the outermost domain only), Dudhia shortwave and RRTM longwave radiation, Monin–Obukhov surface layer physics, and the Noah land surface model (LSM). The domain included 108 vertical levels, with vertical grid spacing increasing from 56 m near the surface to 1190 m at
every 6 h. The outermost domain was allowed to spin up for 6 h before the inner domains were initialized. Physical parameterizations used were Thompson microphysics, YSU planetary boundary layer (PBL) physics, Kain–Fritsch cumulus (for the outermost domain only), Dudhia shortwave and RRTM longwave radiation, Monin–Obukhov surface layer physics, and the Noah land surface model (LSM). The domain included 108 vertical levels, with vertical grid spacing increasing from 56 m near the surface to 1190 m at
, gravity waves are subject to reflection, refraction, instability, and breakdown associated with vertical or lateral wind shears and sharp stratification variations when propagating through a deep atmosphere. In this section, we aim to provide further insight into the possible role of a horizontal wind shear in shaping trailing waves through ray-path calculations using the simulated wind and buoyancy-frequency fields from IOP 6. Each ray is launched from the location of the highest peak of the Southern
, gravity waves are subject to reflection, refraction, instability, and breakdown associated with vertical or lateral wind shears and sharp stratification variations when propagating through a deep atmosphere. In this section, we aim to provide further insight into the possible role of a horizontal wind shear in shaping trailing waves through ray-path calculations using the simulated wind and buoyancy-frequency fields from IOP 6. Each ray is launched from the location of the highest peak of the Southern
-based lidar observations in the lee of New Zealand’s Alps during DEEPWAVE revealed enhanced gravity wave activity in the stratosphere and mesosphere, which lasted about 1–3 days and alternated with quiescent periods ( Kaifler et al. 2015 ). The gravity wave forcing due to passing weather systems, the appearance of tropopause jets, and the middle atmosphere wave response were all observed with a similar frequency and duration of 2–4 days ( Fritts et al. 2016 ; Gisinger et al. 2017 ). The episodic nature
-based lidar observations in the lee of New Zealand’s Alps during DEEPWAVE revealed enhanced gravity wave activity in the stratosphere and mesosphere, which lasted about 1–3 days and alternated with quiescent periods ( Kaifler et al. 2015 ). The gravity wave forcing due to passing weather systems, the appearance of tropopause jets, and the middle atmosphere wave response were all observed with a similar frequency and duration of 2–4 days ( Fritts et al. 2016 ; Gisinger et al. 2017 ). The episodic nature
