High vertical resolution analyses of gravity waves and turbulence at a midlatitude station

[1] We proposed a broad spectral data-analyzing method to study the altitude and seasonal variability of gravity wave (GW)-associated dynamics in the lower atmosphere at a midlatitude by using the radiosonde data from Miramar Nas (32.87°N, 117.15°W), California, during 1998–2008. Generally, the presented primary statistical features of GW parameters and their seasonal variation are consistent with previous radiosonde observations by using the conventional hodograph analysis method based on monochromatic GW theory. These consistencies suggest our proposed analyzing method is feasible in extracting GW parameters from the radiosonde data. More interesting, our analyses can reveal the altitude variations of GW parameters, which have been seldom reported in previous radiosonde observations. Similar to previous observations, most seasonal and height variability of GW parameters is closely connected with tropospheric jet, suggesting the important role of the jet in determining GW parameters as well as the lower atmospheric dynamics and thermal structure. Mainly due to the broad spectral nature of the observed GWs, there are also some differences between our results and previous studies based on monochromatic GW extraction. By using the perturbation of vertical ascent rate, we directly calculated GW momentum and heat fluxes, which can only be indirectly derived from the hodograph analysis. Furthermore, the directly derived heat flux can explain the frequently observed tropospheric inversion in winter. Besides GW parameters, turbulent energy dissipation rate and diffusion coefficient were also derived. The derived turbulence parameters and their altitude variations are in good agreement with radar observations reported elsewhere.

[1]  T. Tsuda,et al.  Radiosonde observations of equatorial atmosphere dynamics over Indonesia: 2. Characteristics of gravity waves , 1994 .

[2]  M. Joan Alexander,et al.  Gravity waves in the tropical lower stratosphere: An observational study of seasonal and interannual variability , 2000 .

[3]  F.-J. Lfibken,et al.  Seasonal variation of turbulent energy dissipation rates at high latitudes as determined by in situ measurements of neutral density fluctuations , 1997 .

[4]  T. Tsuda,et al.  Measurements of vertical eddy diffusivity across the tropopause using radio acoustic sounding system (RASS) , 2007 .

[5]  F. Yi,et al.  A statistical study of gravity waves from radiosonde observations at Wuhan (30° N, 114° E) China , 2005 .

[6]  L. Thomas,et al.  Inertia-gravity waves in the troposphere and lower stratosphere associated with a jet stream exit region , 1999 .

[7]  J. Weinstock.  Energy Dissipation Rates of Turbulence in the Stable Free Atmosphere , 1981 .

[8]  T. Tsuda,et al.  Spectral analysis of temperature and Brunt-Väisälä frequency fluctuations observed by radiosondes , 1991 .

[9]  F. Yi,et al.  Latitudinal and seasonal variations of inertial gravity wave activity in the lower atmosphere over central China , 2007 .

[10]  M. Rapp,et al.  Turbulent energy dissipation rates observed by Doppler MST Radar and by rocket-borne instruments during the MIDAS/MaCWAVE campaign 2002 , 2005 .

[11]  U. Hoppe,et al.  Estimates of turbulent energy dissipation rates from determinations of characteristic vertical wavenumber by EISCAT , 1998 .

[12]  L. Kantha,et al.  On Turbulence and Mixing in the Free Atmosphere Inferred from High-Resolution Soundings , 2008 .

[13]  Nikolai M. Gavrilov,et al.  Turbulence parameter estimations from high-resolution balloon temperature measurements of the MUTSI-2000 campaign , 2005 .

[14]  G. D. Nastrom,et al.  Turbulence eddy dissipation rates from radar observations at 5-20 km at White Sands Missile Range, New mexico , 1997 .

[15]  David C. Fritts,et al.  A Climatology of Gravity Wave Motions in the Mesopause Region at Adelaide, Australia , 1987 .

[16]  Yehui Zhang,et al.  Intensive radiosonde observations of lower tropospheric inversion layers over Yichang, China , 2009 .

[17]  M. Yamamoto,et al.  Seasonal variability of vertical eddy diffusivity in the middle atmosphere: 1. Three‐year observations by the middle and upper atmosphere radar , 1994 .

[18]  G. D. Nastrom,et al.  A brief climatology of eddy diffusivities over White Sands Missile Range, New Mexico , 1997 .

[19]  M. Geller,et al.  Gravity wave kinetic, potential, and vertical fluctuation energies as indicators of different frequency gravity waves , 2010 .

[20]  F. Lübken.  On the extraction of turbulent parameters from atmospheric density fluctuations , 1992 .

[21]  Franz-Josef Lübken,et al.  BUGATTI experiments: Mass spectrometric studies of lower thermosphere eddy mixing and turbulence , 1990 .

[22]  M. Alexander,et al.  Gravity wave dynamics and effects in the middle atmosphere , 2003 .

[23]  Kaoru Sato,et al.  A statistical study of gravity waves in the polar regions based on operational radiosonde data , 2000 .

[24]  N. McFarlane,et al.  The effect of varying the source spectrum of a gravity wave parameterization in a middle atmosphere general circulation model , 1998 .

[25]  M. Geller,et al.  Morphology of gravity‐wave energy as observed from 4 years (1998–2001) of high vertical resolution U.S. radiosonde data , 2003 .

[26]  G. D. Nastrom,et al.  Seasonal variability of turbulence parameters at 2 to 21 km from MST radar measurements at Vandenberg Air Force Base, California , 2005 .

[27]  Global gravity wave activity in the tropopause region from CHAMP radio occultation data , 2008 .

[28]  G. D. Nastrom,et al.  Vertical wavenumber spectra of wind and temperature from high-resolution balloon soundings over Illinois , 1997 .

[29]  R. Vincent,et al.  Interstation correlation of high-latitude lower-stratosphere gravity wave activity: Evidence for planetary wave modulation of gravity waves over Antarctica , 2004 .

[30]  M. Geller,et al.  Vertical fluctuation energy in United States high vertical resolution radiosonde data as an indicator of convective gravity wave sources , 2010 .

[31]  Wayne K. Hocking,et al.  Measurement of turbulent energy dissipation rates in the middle atmosphere by radar techniques: A review , 1985 .

[32]  A. Liu.  Estimate eddy diffusion coefficients from gravity wave vertical momentum and heat fluxes , 2009 .

[33]  T. Dunkerton,et al.  Fluxes of Heat and Constituents Due to Convectively Unstable Gravity Waves , 1985 .

[34]  H. Basha,et al.  High resolution observations of turbulence in the troposphere and lower stratosphere over Gadanki , 2009 .

[35]  R. Vincent,et al.  Wavelet analysis of stratospheric gravity wave packets over Macquarie Island 2. Intermittency and mean-flow accelerations , 2001 .

[36]  B. V. K. Murthy,et al.  Turbulence parameters in the tropical troposphere and lower stratosphere , 2002 .

[37]  R. Walterscheid.  Dynamical cooling induced by dissipating internal gravity waves , 1981 .

[38]  F. Yi,et al.  Latitudinal and seasonal variations of lower atmospheric inertial gravity wave energy revealed by US radiosonde data , 2010 .

[39]  R. Akmaev.  On the energetics of mean‐flow interactions with thermally dissipating gravity waves , 2007 .

[40]  R. Lindzen.  Turbulence and stress owing to gravity wave and tidal breakdown , 1981 .

[41]  M. McIntyre.  On Dynamics and Transport Near the Polar Mesopause in Summer , 1989 .

[42]  M. Geller,et al.  Source spectra information derived from U.S. high-resolution radiosonde data , 2008 .

[43]  R. N. Misra,et al.  First mesospheric turbulence study using coordinated rocket and MST radar measurements over Indian low latitude region , 2008 .

[44]  G. B. Pant,et al.  Seasonal, annual and inter-annual features of turbulence parameters over the tropical station Pune (18°32' N, 73°51' E) observed with UHF wind profiler , 2008 .

[45]  Todd P. Lane,et al.  Observations and numerical modelling of mountain waves over the Southern Alps of New Zealand , 2000 .

[46]  F. Yi,et al.  Radiosonde observations of vertical wave number spectra for gravity waves in the lower atmosphere over Central China , 2006 .

[47]  G. Papen,et al.  Gravity wave characteristics in the lower atmosphere at south pole , 1999 .

[48]  J. Weinstock.  On the Theory of Turbulence in the Buoyancy Subrange of Stably Stratified Flows , 1978 .

[49]  T. Blix,et al.  In situ measurements of the fine-scale structure and turbulence in the mesosphere and lower thermosphere by means of electrostatic positive ion probes , 1990 .

[50]  F. Lübken,et al.  In situ measurements of turbulent energy dissipation rates and eddy diffusion coefficients during MAP/WINE , 1987 .

[51]  R. Vincent,et al.  Wavelet analysis of stratospheric gravity wave packets over Macquarie Island: 1. Wave parameters , 2001 .

[52]  T. Tsuda,et al.  Characteristics of Kelvin waves and gravity waves observed with radiosondes over Indonesia , 1997 .

[53]  S. Eckermann.  Hodographic analysis of gravity waves: Relationships among Stokes parameters, rotary spectra and cross‐spectral methods , 1996 .

[54]  Ling Wang,et al.  Spatial and Temporal Variations of Gravity Wave Parameters. Part I: Intrinsic Frequency, Wavelength, and Vertical Propagation Direction , 2005 .

[55]  R. Wilson,et al.  Turbulent diffusivity in the free atmosphere inferred from MST radar measurements: a review , 2004 .

[56]  O. Coté,et al.  Comparison of radar and in situ measurements of atmospheric turbulence , 2004 .

[57]  M. Rapp,et al.  In situ measurements of mesospheric turbulence during spring transition of the Arctic mesosphere , 2002 .

[58]  C. Williams,et al.  A dual‐wavelength radar technique for measuring the turbulent energy dissipation rate ε , 2000 .

[59]  N. Adams,et al.  Radiosonde observations of partially trapped lee waves over Tasmania, Australia , 1999 .

[60]  S. Rao,et al.  Turbulence characteristics over tropical station Gadanki (13.5°N, 79.2°E) estimated using high-resolution GPS radiosonde data , 2010 .

[61]  M. Joan Alexander,et al.  Gravity wave momentum flux in the lower stratosphere over convection , 1995 .

[62]  Peter F. Lester,et al.  Waves and Turbulence in the Stratosphere , 1974 .

[63]  V. I. Tatarskii.  The effects of the turbulent atmosphere on wave propagation , 1971 .

[64]  David C. Fritts,et al.  Mesospheric Momentum Flux Studies at Adelaide, Australia: Observations and a Gravity Wave–Tidal Interaction Model , 1987 .

[65]  R. Vincent,et al.  Gravity wave activity in the lower atmosphere: Seasonal and latitudinal variations , 1995 .

[66]  D. Fritts,et al.  Gravity wave heat fluxes - A Lagrangian approach , 1988 .

[67]  Rolando R. Garcia,et al.  Implementation of a gravity wave source spectrum parameterization dependent on the properties of convection in the Whole Atmosphere Community Climate Model (WACCM) , 2005 .

[68]  S. Fukao,et al.  Vertical eddy diffusivity in the lower and middle atmosphere: A climatology based on the MU radar observations during 1986–1992 , 1996 .

[69]  M. Alexander,et al.  Interpretations of observed climatological patterns in stratospheric gravity wave variance , 1998 .

[70]  J. Weinstock,et al.  Vertical turbulence diffusivity for weak or strong stable stratification , 1981 .

[71]  S. Rao,et al.  MST radar and radiosonde observations of inertia‐gravity wave climatology over tropical stations: Source mechanisms , 2008 .