Eddy Diffusivities for Momentum and Heat in the Upper Troposphere and Lower Stratosphere Measured by MU Radar and RASS, and a Comparison of Turbulence Model Predictions

Abstract Recently, middle- and upper-atmosphere Doppler radar (MU radar) has enabled the measurement of middle-atmosphere turbulence from radar backscatter Doppler spectra. In this work, eddy diffusivities for momentum Km in the upper troposphere and lower stratosphere during clear-air conditions were derived from direct measurements of the Reynolds stress and vertical gradient of mean wind velocity measured by MU radar. Eddy diffusivity for heat Kh below 8 km was determined from measurements of temperature fluctuations by the Radio Acoustic Sounding System (RASS) attached to the MU radar. The eddy diffusivity for momentum was on the order of 10 m2 s−1 in the upper troposphere and decreased gradually in the stratosphere by an order of magnitude or more. The eddy diffusivity for heat was almost of the same order of magnitude as Km. Estimates of eddy diffusivity from the radar echo power spectral width give fairly good values compared with the direct measurement of Km. Applicability of three turbulence models—the spectral width method, the k–ɛ model modified for stratified flows, and the algebraic stress model—were also examined, using radar observation values of turbulent kinetic energy k and turbulent energy dissipation rate ɛ together with atmospheric stability observations from rawinsonde data. It is concluded that the algebraic stress model shows the best fit with the direct measurement of Km, even in the free atmosphere above the atmospheric boundary layer once k and ɛ values are obtained from observations or a model.

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Internal gravity wave selection in the upper troposphere and lower stratosphere observed by the MU radar: Preliminary results

Pure and Applied Geophysics ◽

10.1007/bf00874470 ◽

1989 ◽

Vol 130 (2-3) ◽

pp. 481-495 ◽

Cited By ~ 24

Author(s):

Manabu D. Yamanaka ◽

Shoichiro Fukao ◽

Hiromasa Matsumoto ◽

Toru Sato ◽

Toshitaka Tsuda ◽

...

Keyword(s):

Gravity Wave ◽

Lower Stratosphere ◽

Internal Gravity Wave ◽

Upper Troposphere ◽

Preliminary Results ◽

Mu Radar

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Internal Gravity Wave Selection in the Upper Troposphere and Lower Stratosphere Observed by the MU Radar: Preliminary Results

Middle Atmosphere ◽

10.1007/978-3-0348-5825-0_20 ◽

1989 ◽

pp. 481-495 ◽

Cited By ~ 1

Author(s):

Manabu D. Yamanaka ◽

Shoichiro Fukao ◽

Hiromasa Matsumoto ◽

Toru Sato ◽

Toshitaka Tsuda ◽

...

Keyword(s):

Gravity Wave ◽

Lower Stratosphere ◽

Internal Gravity Wave ◽

Upper Troposphere ◽

Preliminary Results ◽

Mu Radar

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Horizontal Wavenumber Spectra of Vertical Vorticity and Horizontal Divergence in the Upper Troposphere and Lower Stratosphere

Journal of the Atmospheric Sciences ◽

10.1175/jas3864.1 ◽

2007 ◽

Vol 64 (3) ◽

pp. 1017-1025 ◽

Cited By ~ 57

Author(s):

Erik Lindborg

Keyword(s):

Lower Stratosphere ◽

Velocity Structure ◽

Internal Gravity Waves ◽

Energy Cascade ◽

Stratified Turbulence ◽

Measured Velocity ◽

Upper Troposphere ◽

Vertical Vorticity ◽

Order Of Magnitude ◽

Point Correlation

Abstract The author shows that the horizontal two-point correlations of vertical vorticity and the associated vorticity wavenumber spectrum can be constructed from previously measured velocity structure functions in the upper troposphere and lower stratosphere. The spectrum has a minimum around k = 10−2 cycles per kilometer (cpkm) corresponding to wavelengths of 100 km. For smaller wavenumbers it displays a k−1 range and for higher wavenumbers, corresponding to mesoscale motions, it grows as k1/3. The two-point correlation of horizontal divergence of horizontal velocity and the associated horizontal spectrum is also constructed. The horizontal divergence spectrum is of the same order of magnitude as the vorticity spectrum in the mesoscale range and show similar inertial range scaling. It is argued that these results show that the mesoscale motions are not dominated by internal gravity waves. Instead, the author suggests that the dynamic origin of the k1/3 range is stratified turbulence. However, in contrast to Lilly, the author finds that stratified turbulence is not a phenomenon associated with an upscale energy cascade, but with a downscale energy cascade.

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Predicting S-duct flow using a composite algebraic stress model

AIAA Journal ◽

10.2514/3.13824 ◽

1998 ◽

Vol 36 ◽

pp. 327-335

Author(s):

T. Jongen ◽

G. Mompean ◽

T. B. Gatski

Keyword(s):

Stress Model ◽

Duct Flow ◽

Algebraic Stress Model

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High lift airfoil flow simulation using a wall-corrected Algebraic Stress Model

10.2514/6.1993-3109 ◽

1993 ◽

Author(s):

G. FRESKOS ◽

S. UNDREINER ◽

H. MINH

Keyword(s):

Flow Simulation ◽

Stress Model ◽

High Lift ◽

Algebraic Stress Model ◽

Airfoil Flow

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Correction: Improvements to an Explicit Algebraic Stress Model for Turbulent Jet Mixing Predictions

AIAA Scitech 2019 Forum ◽

10.2514/6.2019-0325.c1 ◽

2019 ◽

Author(s):

Nicholas J. Georgiadis ◽

Dennis A. Yoder

Keyword(s):

Turbulent Jet ◽

Stress Model ◽

Jet Mixing ◽

Algebraic Stress Model

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NUMERICAL STUDY OF NONISOTHERMAL THREE-DIMENSIONAL ROOM AIRFLOW : Room airflow analysis by means of algebraic stress model Part 4

Journal of Architecture Planning and Environmental Engineering (Transactions of AIJ) ◽

10.3130/aijax.443.0_15 ◽

1993 ◽

Vol 443 (0) ◽

pp. 15-20

Author(s):

Shinsuke KATO ◽

Shuzo MURAKAMI ◽

Yasushi KONDO

Keyword(s):

Numerical Study ◽

Three Dimensional ◽

Stress Model ◽

Algebraic Stress Model

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Measurements of the upper troposphere and lower stratosphere during tropical cyclones using the GPS radio occultation technique

Advances in Space Research ◽

10.1016/j.asr.2010.05.031 ◽

2011 ◽

Vol 47 (2) ◽

pp. 348-355 ◽

Cited By ~ 7

Author(s):

Riccardo Biondi ◽

Torsten Neubert ◽

Stig Syndergaard ◽

Johannes Nielsen

Keyword(s):

Tropical Cyclones ◽

Radio Occultation ◽

Lower Stratosphere ◽

Upper Troposphere ◽

Gps Radio Occultation

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A Case Study of Mass Transport during the East-West Oscillation of the Asian Summer Monsoon Anticyclone

Advances in Meteorology ◽

10.1155/2017/5174025 ◽

2017 ◽

Vol 2017 ◽

pp. 1-13 ◽

Cited By ~ 2

Author(s):

Jiali Luo ◽

Jiayao Song ◽

Hongying Tian ◽

Lei Liu ◽

Xinlei Liang

Keyword(s):

Lower Stratosphere ◽

Asian Summer Monsoon ◽

Chemical Transport ◽

Upward Motion ◽

High Concentration ◽

Upper Troposphere ◽

Asian Summer ◽

Mode Tm ◽

East West

We use ERA-Interim reanalysis, MLS observations, and a trajectory model to examine the chemical transport and tracers distribution in the Upper Troposphere and Lower Stratosphere (UTLS) associated with an east-west oscillation case of the anticyclone in 2016. The results show that the spatial distribution of water vapor (H2O) was more consistent with the location of the anticyclone than carbon monoxide (CO) at 100 hPa, and an independent relative high concentration center was only found in H2O field. At 215 hPa, although the anticyclone center also migrated from the Tibetan Mode (TM) to the Iranian Mode (IM), the relative high concentration centers of both tracers were always colocated with regions where upward motion was strong in the UTLS. When the anticyclone migrated from the TM, air within the anticyclone over Tibetan Plateau may transport both westward and eastward but was always within the UTLS. The relative high concentration of tropospheric tracers within the anticyclone in the IM was from the east and transported by the westward propagation of the anticyclone rather than being lifted from surface directly. Air within the relative high geopotential height centers over Western Pacific was partly from the main anticyclone and partly from lower levels.

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