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the perturbation part of the atmospheric pressure, ρ is the mean air density, and ν is the kinematic molecular viscosity. Repeated indices indicate summation, and bars denote time averaging. Our approach is to determine as many terms as possible. We unfortunately cannot determine the terms that describe horizontal advection and horizontal shear. We also cannot calculate the pressure correlation , which requires high-frequency pressure measurements that were not made during the Terrain
the perturbation part of the atmospheric pressure, ρ is the mean air density, and ν is the kinematic molecular viscosity. Repeated indices indicate summation, and bars denote time averaging. Our approach is to determine as many terms as possible. We unfortunately cannot determine the terms that describe horizontal advection and horizontal shear. We also cannot calculate the pressure correlation , which requires high-frequency pressure measurements that were not made during the Terrain
stratosphere. Ozone concentration is obtained on the GV with a chemiluminescence technique ( Ridley et al. 1992 ). More instrument details are available from the NCAR and University of Wyoming flight facilities. 3. Flight level data and wave kinematics One advantage of the racetrack path is that differences in GPS altitude and pressure between the two legs can be used to evaluate the degree of geostrophy in the mean flow. We computed the component of the geostrophic wind velocity along the x B direction
stratosphere. Ozone concentration is obtained on the GV with a chemiluminescence technique ( Ridley et al. 1992 ). More instrument details are available from the NCAR and University of Wyoming flight facilities. 3. Flight level data and wave kinematics One advantage of the racetrack path is that differences in GPS altitude and pressure between the two legs can be used to evaluate the degree of geostrophy in the mean flow. We computed the component of the geostrophic wind velocity along the x B direction
flow kinematics by the Oregon Coast Range and Cascades during IMPROVE-2. Mon. Wea. Rev. , 136 , 3894 – 3916 . Cox , J. A. W. , W. J. Steenburgh , and J. C. Shafer , 2005 : The kinematic structure of a Wasatch Mountain winter storm during IPEX IOP3. Mon. Wea. Rev. , 133 , 521 – 542 . Doyle , J. D. , and R. B. Smith , 2003 : Mountain waves over the Hohe Tauern. Quart. J. Roy. Meteor. Soc. , 129 , 799 – 823 . Doyle , J. D. , and Q. Jiang , 2006 : Observations and
flow kinematics by the Oregon Coast Range and Cascades during IMPROVE-2. Mon. Wea. Rev. , 136 , 3894 – 3916 . Cox , J. A. W. , W. J. Steenburgh , and J. C. Shafer , 2005 : The kinematic structure of a Wasatch Mountain winter storm during IPEX IOP3. Mon. Wea. Rev. , 133 , 521 – 542 . Doyle , J. D. , and R. B. Smith , 2003 : Mountain waves over the Hohe Tauern. Quart. J. Roy. Meteor. Soc. , 129 , 799 – 823 . Doyle , J. D. , and Q. Jiang , 2006 : Observations and
-REX, GAUS was located near Independence in Owens Valley ( Fig. 2 ) and launched 102 radiosondes during the 2-month period. These soundings were collected to obtain kinematic and thermodynamic data for the valley atmosphere and, in conjunction with NCAR Mobile GAUS (MGAUS) soundings launched from the sites upwind of the Sierra Nevada, to detect changes induced on the lee side by mountain waves and rotors. Note that only GAUS data collected in Owens Valley are used in this study although we also processed
-REX, GAUS was located near Independence in Owens Valley ( Fig. 2 ) and launched 102 radiosondes during the 2-month period. These soundings were collected to obtain kinematic and thermodynamic data for the valley atmosphere and, in conjunction with NCAR Mobile GAUS (MGAUS) soundings launched from the sites upwind of the Sierra Nevada, to detect changes induced on the lee side by mountain waves and rotors. Note that only GAUS data collected in Owens Valley are used in this study although we also processed
. Meteor. Climatol. , 47 , 2929 – 2945 . 10.1175/2008JAMC1878.1 Browning, K. A. , and Wexler R. , 1968 : The determination of kinematic properties of a wind field using Doppler radar. J. Appl. Meteor. , 7 , 105 – 113 . 10.1175/1520-0450(1968)007<0105:TDOKPO>2.0.CO;2 Calhoun, R. , Heap R. , Princevac M. , Newsom R. , Fernando H. , and Ligon D. , 2006 : Virtual towers using coherent Doppler lidar during the Joint Urban 2003 Dispersion Experiment. J. Appl. Meteor. , 45 , 1116
. Meteor. Climatol. , 47 , 2929 – 2945 . 10.1175/2008JAMC1878.1 Browning, K. A. , and Wexler R. , 1968 : The determination of kinematic properties of a wind field using Doppler radar. J. Appl. Meteor. , 7 , 105 – 113 . 10.1175/1520-0450(1968)007<0105:TDOKPO>2.0.CO;2 Calhoun, R. , Heap R. , Princevac M. , Newsom R. , Fernando H. , and Ligon D. , 2006 : Virtual towers using coherent Doppler lidar during the Joint Urban 2003 Dispersion Experiment. J. Appl. Meteor. , 45 , 1116
then be solved for using the kinematic relation w ′ = U (∂ η /∂ x ), continuity u ′ = − U (∂ η /∂ z ), and the Bernoulli relation p ′ = − ρ 0 Uu ′, yielding where ρ 0 = 1.292 kg m −3 is the reference density. The Queney solution for an atmosphere with U = 10 m s −1 , N = 10 −2 s −1 , a = 7 km, and h m = 1000 m is shown in Fig. 1a . The momentum and energy fluxes for the Queney solution are MF = −( π /4) ρ 0 NUh m 2 and EF = ( π /4) ρ 0 NU 2 h m 2 . These analytic solutions can
then be solved for using the kinematic relation w ′ = U (∂ η /∂ x ), continuity u ′ = − U (∂ η /∂ z ), and the Bernoulli relation p ′ = − ρ 0 Uu ′, yielding where ρ 0 = 1.292 kg m −3 is the reference density. The Queney solution for an atmosphere with U = 10 m s −1 , N = 10 −2 s −1 , a = 7 km, and h m = 1000 m is shown in Fig. 1a . The momentum and energy fluxes for the Queney solution are MF = −( π /4) ρ 0 NUh m 2 and EF = ( π /4) ρ 0 NU 2 h m 2 . These analytic solutions can
downslope windstorm: Numerical simulations and comparison with observations . J. Atmos. Sci. , 57 , 1105 – 1131 . Colle , B. , and C. F. Mass , 1996 : An observational and modeling study of the interaction of low level southwesterly flow with the Olympic Mountains during COAST IOP4 . Mon. Wea. Rev. , 124 , 2152 – 2175 . Colle , B. , Y. Lin , S. Medina , and B. F. Smull , 2008 : Orographic modification of convection and flow kinematics by the Oregon Coast Range and cascades during
downslope windstorm: Numerical simulations and comparison with observations . J. Atmos. Sci. , 57 , 1105 – 1131 . Colle , B. , and C. F. Mass , 1996 : An observational and modeling study of the interaction of low level southwesterly flow with the Olympic Mountains during COAST IOP4 . Mon. Wea. Rev. , 124 , 2152 – 2175 . Colle , B. , Y. Lin , S. Medina , and B. F. Smull , 2008 : Orographic modification of convection and flow kinematics by the Oregon Coast Range and cascades during
wind vector and vertical measurement without the need to scan in multiple beam directions, resulting in a higher temporal resolution (approximately 5 min in the horizontal and 30 s in the vertical). MISS is a mobile system that could be transported to the area of strongest wave activity. During IOP 8, MISS was located at the airport north of Independence ( Fig. 1c ). Given the importance of documenting the upstream thermodynamic and kinematic flow structure for interpreting the mountain wave
wind vector and vertical measurement without the need to scan in multiple beam directions, resulting in a higher temporal resolution (approximately 5 min in the horizontal and 30 s in the vertical). MISS is a mobile system that could be transported to the area of strongest wave activity. During IOP 8, MISS was located at the airport north of Independence ( Fig. 1c ). Given the importance of documenting the upstream thermodynamic and kinematic flow structure for interpreting the mountain wave
thermosonde, and a K-band radar were deployed to monitor the incoming flow characteristics. A more detailed description of the instrumentation can be found in Grubišić et al. (2008) . Three research aircraft were used in the T-REX campaign to document the mountain wave–rotor coupled system over Owens Valley and to provide kinematic and thermodynamic information about airflow upstream and downstream of the Sierra Nevada range. The T-REX aircraft included the National Science Foundation (NSF)–NCAR High
thermosonde, and a K-band radar were deployed to monitor the incoming flow characteristics. A more detailed description of the instrumentation can be found in Grubišić et al. (2008) . Three research aircraft were used in the T-REX campaign to document the mountain wave–rotor coupled system over Owens Valley and to provide kinematic and thermodynamic information about airflow upstream and downstream of the Sierra Nevada range. The T-REX aircraft included the National Science Foundation (NSF)–NCAR High
. Initial upstream blocking is gradually reduced and winds amplify throughout the troposphere. The low-level wind switches from initially southerly to westerly and finally to northerly, as the front passes. At the same time, the potential temperature profiles remain relatively unaltered, with the rather uniform profiles of stability and wind shear promoting the generation of long trapped waves or even upward-propagating mountain waves. The kinematic characteristics of the valley atmosphere in the four
. Initial upstream blocking is gradually reduced and winds amplify throughout the troposphere. The low-level wind switches from initially southerly to westerly and finally to northerly, as the front passes. At the same time, the potential temperature profiles remain relatively unaltered, with the rather uniform profiles of stability and wind shear promoting the generation of long trapped waves or even upward-propagating mountain waves. The kinematic characteristics of the valley atmosphere in the four
