Search Results

You are looking at 1 - 10 of 11 items for :

  • Middle atmosphere x
  • Fifth International Symposium on Tropospheric Profiling (ISTP) x
  • Journal of Atmospheric and Oceanic Technology x
  • All content x
Clear All
Simon P. Alexander and Toshitaka Tsuda

et al. 1992 ), boundary layer heat fluxes ( Angevine et al. 1993 ), humidity profiles ( Furumoto and Tsuda 2001 ), fog inversions ( Bonino et al. 1981 ), and gravity waves ( Tsuda et al. 1994 ; Yamamoto et al. 1996 ). Recent experiments with the very high-frequency (VHF) middle- and upper-atmosphere (MU) radar RASS in Shigaraki, Japan (located at 34.85°N, 136.10°E; 370 m MSL), have shown fluctuations in turbulent parameters, such as the turbulent spectral width σ t and kinetic energy

Full access
Danny E. Scipión, Phillip B. Chilson, Evgeni Fedorovich, and Robert D. Palmer

the middle atmosphere. J. Atmos. Terr. Phys. , 46 , 739 – 753 . 10.1016/0021-9169(84)90055-2 Gage, K. S. , Williams C. R. , and Ecklund W. L. , 1994 : UHF wind profilers: A new tool for diagnosing and classifying tropical convective cloud systems. Bull. Amer. Meteor. Soc. , 75 , 2289 – 2294 . 10.1175/1520-0477(1994)075<2289:UWPANT>2.0.CO;2 Grimsdell, A. W. , and Angevine W. M. , 2002 : Observation of the afternoon transition of the convective boundary layer. J. Appl. Meteor

Full access
B. L. Cheong, R. D. Palmer, T-Y. Yu, K-F. Yang, M. W. Hoffman, S. J. Frasier, and F. J. Lopez-Dekker

1. Introduction Very high-frequency (VHF) and ultrahigh-frequency (UHF) profiling radars have been used widely in both the operational and research arenas for observations of the structure and dynamics of the atmosphere. In particular, this type of radar has proven important for studies of turbulence, momentum fluxes, and gravity waves (e.g., Röttger and Larsen 1990 ; Gage 1990 ; and references therein). One of the more common techniques for obtaining profiles of the three-dimensional wind

Full access
Matthias Grzeschik, Hans-Stefan Bauer, Volker Wulfmeyer, Dirk Engelbart, Ulla Wandinger, Ina Mattis, Dietrich Althausen, Ronny Engelmann, Matthias Tesche, and Andrea Riede

is the second fully operational worldwide lidar system after CARL and the first one with a fully autonomous data retrieval scheme ( Mattis and Jaenisch 2006 ). RAMSES is based on an injection-seeded frequency-tripled Nd:YAG laser with a total pulse energy of up to 1.6 J. Only third-harmonic radiation at 354.7 nm is emitted into the atmosphere. The typical pulse energy at this wavelength chosen for operational conditions is 300 mJ. The pulse repetition rate is 30 Hz. The laser beam is expanded

Full access
Thierry Leblanc, I. Stuart McDermid, and Robin A. Aspey

. , Waltman W. B. , and Pauls T. A. , 1995 : Ground-based measurements of water vapor in the middle atmosphere. J. Geophys. Res. , 100 , 2927 – 2939 . 10.1029/94JD02952 Oltmans, S. J. , and Hofmann D. J. , 1995 : Increase in lower stratospheric water vapor at a midlatitude Northern Hemisphere site from 1981 to 1994. Nature , 374 , 146 – 149 . 10.1038/374146a0 Sherlock, V. , Garnier A. , Hauchecorne A. , and Keckhut P. , 1999a : Methodology for the independent calibration of

Full access
Laura Bianco, James M. Wilczak, and Allen B. White

of atmospheric turbulence parameters from radar backscatter Doppler spectra—I. Theory. J. Atmos. Terr. Phys. , 45 , 89 – 102 . 10.1016/S0021-9169(83)80013-0 Hocking, W. K. , 1985 : Measurement of turbulent energy dissipation rates in the middle atmosphere by radar technique: A review. Radio Sci. , 20 , 1403 – 1422 . 10.1029/RS020i006p01403 Hocking, W. K. , 1986 : Observations and measurements of turbulence in the middle atmosphere with a VHF radar. J. Atmos. Terr. Phys. , 48

Full access
Ronny Engelmann, Ulla Wandinger, Albert Ansmann, Detlef Müller, Egidijus Žeromskis, Dietrich Althausen, and Birgit Wehner

set up next to the stationary three-wavelength Raman lidar at the IfT site in Leipzig. The horizontal distance between the two lidar beams was less than 10 m. The bias in the flux measurements introduced by this lateral displacement is negligibly small for flux observations in the middle and upper PBL ( Kristensen et al. 1997 ). The data acquisition computers of the two systems were synchronized via an Internet-based time server. Data were stored on a fixed time grid every 5 s. A vertical

Full access
Ulrich Löhnert, S. Crewell, O. Krasnov, E. O’Connor, and H. Russchenberg

1. Introduction Continuous profiling of the thermodynamic state of the atmosphere is becoming more and more important in support of mesoscale models, which are increasingly employed for numerical weather prediction (NWP). Especially the development of the boundary layer (BL), for example, its diurnal cycle or its influence on the initiation of convection, is crucial for the correct prediction of regional weather scales, including severe events, such as extreme precipitation. In this context the

Full access
Daniela Nowak, Dominique Ruffieux, Judith L. Agnew, and Laurent Vuilleumier

traverse the atmosphere. The resulting backscatter profile (signal strength versus height) is processed to detect cloud-base height. The ceilometer can detect up to three cloud layers simultaneously and retrieve cloud heights every 30 s with a vertical resolution of 15 m up to 7.5 km above the ground. The minimum vertical visibility that can be measured is 15 m (e.g., in case of fog). A disadvantage of this system is that high cirrus clouds can hardly be detected because they often occur above 7.5 km

Full access
Edwin F. Campos, Wayne Hocking, and Frédéric Fabry

radar profilers as calibration tools for scanning radars. J. Appl. Meteor. , 39 , 2209 – 2222 . 10.1175/1520-0450(2001)040<2209:DRPACT>2.0.CO;2 Hocking, W. K. , 1985 : Measurement of turbulent energy dissipation rates in the middle atmosphere by radar techniques: A review. Radio Sci. , 20 , 1403 – 1422 . 10.1029/RS020i006p01403 Hocking, W. K. , and Vincent R. A. , 1982 : Comparative observations of D- region HF partial reflections at 2 and 6 MHz. J. Geophys. Res. , 87 , 7615

Full access