scholarly journals The interaction between the tropopause inversion layer and the inertial gravity wave activities revealed by radiosonde observations at a midlatitude station

2015 ◽  
Vol 120 (16) ◽  
pp. 8099-8111 ◽  
Author(s):  
Yehui Zhang ◽  
Shaodong Zhang ◽  
Chunming Huang ◽  
Kaiming Huang ◽  
Yun Gong ◽  
...  
Keyword(s):  
Gravity Wave ◽  
Inversion Layer

scholarly journals Atmospheric Conditions during the Deep Propagating Gravity Wave Experiment (DEEPWAVE)

2017 ◽  
Vol 145 (10) ◽  
pp. 4249-4275 ◽  
Author(s):  
Sonja Gisinger ◽  
Andreas Dörnbrack ◽  
Vivien Matthias ◽  
James D. Doyle ◽  
Stephen D. Eckermann ◽  
...  
Keyword(s):  
New Zealand ◽  
Gravity Wave ◽  
Inversion Layer ◽  
Polar Vortex ◽  
Polar Front ◽  
Atmospheric Conditions ◽  
Mountain Waves ◽  
Wave Experiment ◽  
Stratospheric Wind ◽  
Antarctic Polar Vortex

This paper describes the results of a comprehensive analysis of the atmospheric conditions during the Deep Propagating Gravity Wave Experiment (DEEPWAVE) campaign in austral winter 2014. Different datasets and diagnostics are combined to characterize the background atmosphere from the troposphere to the upper mesosphere. How weather regimes and the atmospheric state compare to climatological conditions is reported upon and how they relate to the airborne and ground-based gravity wave observations is also explored. Key results of this study are the dominance of tropospheric blocking situations and low-level southwesterly flows over New Zealand during June–August 2014. A varying tropopause inversion layer was found to be connected to varying vertical energy fluxes and is, therefore, an important feature with respect to wave reflection. The subtropical jet was frequently diverted south from its climatological position at 30°S and was most often involved in strong forcing events of mountain waves at the Southern Alps. The polar front jet was typically responsible for moderate and weak tropospheric forcing of mountain waves. The stratospheric planetary wave activity amplified in July leading to a displacement of the Antarctic polar vortex. This reduced the stratospheric wind minimum by about 10 m s−1 above New Zealand making breaking of large-amplitude gravity waves more likely. Satellite observations in the upper stratosphere revealed that orographic gravity wave variances for 2014 were largest in May–July (i.e., the period of the DEEPWAVE field phase).

The Tropopause Inversion Layer Interaction With the Inertial Gravity Wave Activities and Its Latitudinal Variability

2019 ◽  
Vol 124 (14) ◽  
pp. 7512-7522
Author(s):  
Yehui Zhang ◽  
Shaodong Zhang ◽  
Chunming Huang ◽  
Kaiming Huang ◽  
Yun Gong
Keyword(s):  
Gravity Wave ◽  
Inversion Layer ◽  
Layer Interaction

scholarly journals Long-term Lidar Observations of the Gravity Wave Activity near the Mesopause at Arecibo

2018 ◽  
Author(s):  
Xianchang Yue ◽  
Jonathan S. Friedman ◽  
Qihou Zhou ◽  
Xiongbin Wu ◽  
Jens Lautenbach
Keyword(s):  
Potential Energy ◽  
Gravity Wave ◽  
Inversion Layer ◽  
Lower Thermosphere ◽  
Temperature Inversion ◽  
Temperature Structure ◽  
Mean Temperature ◽  
The Mean ◽  
Highly Correlated ◽  
Lidar Observations

Abstract. 11-years long K Doppler lidar observations of temperature profiles in the mesosphere and lower thermosphere (MLT) between 85 and 100 km, conducted at the Arecibo Observatory, Puerto Rico (18.35° N, 66.75° W), are used to estimate seasonal variations of the mean temperature, the squared Brunt-Väisälä frequency, and the gravity wave potential energy in a composite year. The following unique features are obtained: (1) The mean temperature structure shows similar characteristics as a prior report based on a smaller dataset: (2) The profiles of the squared Brunt-Väisälä frequency usually reach the maxima at or just below the temperature inversion layer when that layer is present. The first complete range-resolved climatology of potential energy of temperature fluctuations in the tropical MLT exhibits an altitude dependent combination of annual oscillation (AO) and semiannual oscillation (SAO). Between 88 to 96 km altitude, the amplitudes of AO and SAO are comparable, and their phases are almost the same and quite close to day of year (DOY) 100. Below 88 km, the SAO amplitude is significantly larger than AO and the AO phase shifts to DOY 200 and after. At 97 to 98 km altitude, the amplitudes of AO and SAO reach their minima, and both phases shift significantly. Above that, the AO amplitude becomes greater. The annual mean potential energy profile reaches the minimum at 91 to 92 km altitude. The altitude-dependent SAO of the potential energy is found to be highly correlated with the satellite observed mean zonal winds reported in the literature.

scholarly journals Gravity Wave Dynamics in a Mesospheric Inversion Layer: 1. Reflection, Trapping, and Instability Dynamics

2018 ◽  
Vol 123 (2) ◽  
pp. 626-648 ◽  
Author(s):  
David C. Fritts ◽  
Brian Laughman ◽  
Ling Wang ◽  
Thomas S. Lund ◽  
Richard L. Collins
Keyword(s):  
Gravity Wave ◽  
Inversion Layer ◽  
Wave Dynamics

scholarly journals Gravity Wave Dynamics in a Mesospheric Inversion Layer: 2. Instabilities, Turbulence, Fluxes, and Mixing

2018 ◽  
Vol 123 (2) ◽  
pp. 649-670 ◽  
Author(s):  
David C. Fritts ◽  
Ling Wang ◽  
Brian Laughman ◽  
Thomas S. Lund ◽  
Richard L. Collins
Keyword(s):  
Gravity Wave ◽  
Inversion Layer ◽  
Wave Dynamics ◽  
Layer 2

A theoretical model analysis of the sudden narrow temperature-layer formation observed in the ALOHA-93 Campaign

2002 ◽  
Vol 80 (12) ◽  
pp. 1543-1558 ◽  
Author(s):  
H Hur ◽  
T Y Huang ◽  
Z Zhao ◽  
P Karunanayaka ◽  
T F Tuan
Keyword(s):  
Energy Dissipation ◽  
Gravity Wave ◽  
Temperature Rise ◽  
Critical Level ◽  
Inversion Layer ◽  
Phase Speed ◽  
Temperature Inversion ◽  
Critical Layer ◽  
Mean Flow ◽  
Wind Profiles

The behavior of temperature and wind profiles observed on 21 October 1993 in the ALOHA-93 Campaign is theoretically and numerically analyzed. A sudden temperature rise took place in a very narrow vertical region (3–4 km) at about 87 km. Simultaneously observed radar wind profiles and mesospheric airglow wave structures that show a horizontal phase speed of 35 m/s and a period of about half an hour strongly suggest that a critical level may occur in the proximity of that altitude and that the energy dissipation due to the interaction of the gravity wave with the critical level causes the temperature rise. The numerical model used is a solution to the gravity wave – mean-flow interaction in the critical layer, including a simple cooling mechanism and a wave-energy dissipation simulated by the "optical model" technique. The solutions for the temperature variations so obtained show good agreement with the observed temperature profiles at different times, providing a quantitative explanation for the temperature inversion layer as a phenomenon of gravity wave – critical layer interaction. PACS Nos.: 91.10V, 94.10D

scholarly journals Planetary wave-gravity wave interactions during mesospheric inversion layer events

2013 ◽  
Vol 118 (7) ◽  
pp. 4503-4515 ◽  
Author(s):  
K. Ramesh ◽  
S. Sridharan ◽  
K. Raghunath ◽  
S. Vijaya Bhaskara Rao ◽  
Y. Bhavani Kumar
Keyword(s):  
Gravity Wave ◽  
Planetary Wave ◽  
Inversion Layer ◽  
Wave Interactions

scholarly journals An intercomparison of stratospheric gravity wave potential energy densities from METOP GPS-radio occultation measurements and ECMWF model data

2017 ◽  
Author(s):  
Markus Rapp ◽  
Andreas Dörnbrack ◽  
Bernd Kaifler
Keyword(s):  
Potential Energy ◽  
Gravity Wave ◽  
Radio Occultation ◽  
Inversion Layer ◽  
Small Scale ◽  
Temperature Profiles ◽  
Model Data ◽  
Data Set ◽  
Median Difference ◽  
Mean Temperature

Abstract. Temperature profiles based on radio occultation (RO) measurements with the operational European METOP-satellites are used to derive monthly mean global distributions of stratospheric (20–40 km) gravity wave (GW) potential energy densities (EP) for the period July 2014–December 2016. In order to test whether the sampling and data quality of this data set is sufficient for scientific analysis we investigate to which degree the METOP-observations agree quantitatively with ECMWF operational analysis (IFS-data) and reanalysis (ERA-Interim) data. A systematic comparison between corresponding monthly mean temperature fields determined for a latitude-longitude-altitude grid of 5° by 10° by 1 km is carried out. This yields very low systematic differences between RO and model data below 30 km (i.e., median temperature differences is between −0,2 and +0,3 K) which increases with height to yield median differences of +1,0 K at 34 km and +2,2 K at 40 km. Comparing EP)-values for three selected locations at which also ground based lidar measurements are available yields excellent agreement between RO and IFS-data below 35 km. ERA-Interim underestimates EP) under conditions of strong local mountain wave forcing over Norther Scandinavia which is apparently not resolved by the model. Above 35 km, RO-values are consistently much larger than model values which is likely caused by the model sponge layer which damps small scale fluctuations above ~ 32 km altitude. The comparison between RO and lidar data reveals very good qualitative agreement in terms of the seasonal variation of EP), however, RO-values are consistently smaller than lidar values by about a factor of two. This discrepancy is likely caused by the very different sampling characteristics of RO and lidar observations. Direct comparison of the global data set of RO and model EP)-fields shows large correlation coefficients (0.4–1.0) with a general degradation with increasing altitude. Concerning absolute differences between observed and modelled EP)-values, the median difference is relatively small at all altitudes (but increasing with altitude) with an exception between 20 and 25 km where the median difference between RO- and model-data is increased and where also the corresponding variability is found to be very large. The reason for this is identified as an artifact of the EP)-algorithm: this erroneously interprets the pronounced climatological feature of the tropical tropopause inversion layer (TTIL) as GW activity hence yielding very large EP)-values in this area and also large differences between model and observations. This is because the RO-data show a more pronounced TTIL than IFS and ERA-Interim. We suggest a correction for this effect based on an estimate of this `artificial' EP) using monthly mean zonal mean temperature profiles. This correction may be used in the future to study, for example, the annual cycle of zonal mean GW activity using the here considered data.

Spectrum of a 2D electron gas in an inversion layer

1985 ◽  
Vol 146 (7) ◽  
pp. 531 ◽  
Author(s):  
Yu.A. Bychkov ◽  
E.I. Rashba
Keyword(s):  
Inversion Layer ◽  
Electron Gas
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