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(the transition layer between PBL and the free troposphere) are not well understood and thus are not well parameterized in atmospheric models. Observations of fluxes covering the entire PBL and the entrainment zone are rare. With respect to aerosols, vertical transport is even more complicated because the ascent of particles is often combined with water uptake because of a relative humidity increase with height in the PBL. The particle mass concentration and optical and microphysical properties
(the transition layer between PBL and the free troposphere) are not well understood and thus are not well parameterized in atmospheric models. Observations of fluxes covering the entire PBL and the entrainment zone are rare. With respect to aerosols, vertical transport is even more complicated because the ascent of particles is often combined with water uptake because of a relative humidity increase with height in the PBL. The particle mass concentration and optical and microphysical properties
; Klipp and Mahrt 2004 ; Baas et al. 2006 ). In addition, the separation of the atmospheric variables into a turbulent component and a mean or slowly variable component can be ill posed, especially for statistics such as variances and fluxes for challenging conditions such as stable boundary layers ( Kaimal and Finnigan 1994 ; Mahrt 1998 ; Vickers and Mahrt 2003 ) and larger-scale forcing such as with a density current and a frontal passage ( Piper and Lundquist 2004 ). The standard analysis
; Klipp and Mahrt 2004 ; Baas et al. 2006 ). In addition, the separation of the atmospheric variables into a turbulent component and a mean or slowly variable component can be ill posed, especially for statistics such as variances and fluxes for challenging conditions such as stable boundary layers ( Kaimal and Finnigan 1994 ; Mahrt 1998 ; Vickers and Mahrt 2003 ) and larger-scale forcing such as with a density current and a frontal passage ( Piper and Lundquist 2004 ). The standard analysis
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
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
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
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
. Correspondingly, there are 200 × 200 × 200 grid points. The time discretization is 1 s. The following external parameters were assigned during the run: the free-atmosphere horizontal wind was set to 5 m s −1 in the x direction and 0 m s −1 in the y direction; the free-atmosphere potential temperature gradient was 0.004 K m −1 ; and the surface kinematic heat flux, surface kinematic moisture flux, and surface roughness length were 0.2 K m s −1 , 10 −4 m s −1 , and 0.01 m, respectively. A subset of the
. Correspondingly, there are 200 × 200 × 200 grid points. The time discretization is 1 s. The following external parameters were assigned during the run: the free-atmosphere horizontal wind was set to 5 m s −1 in the x direction and 0 m s −1 in the y direction; the free-atmosphere potential temperature gradient was 0.004 K m −1 ; and the surface kinematic heat flux, surface kinematic moisture flux, and surface roughness length were 0.2 K m s −1 , 10 −4 m s −1 , and 0.01 m, respectively. A subset of the
profiling. COST Office, Brussels, Belgium, Final Rep., in press . Gossard, E. E. , Chadwick R. B. , Neff W. D. , and Moran K. P. , 1982 : The use of ground-based Doppler radars to measure gradients, fluxes, and structure parameters in elevated layers. J. Appl. Meteor. , 21 , 211 – 226 . 10.1175/1520-0450(1982)021<0211:TUOGBD>2.0.CO;2 Gossard, E. E. , Wolfe D. E. , and Stankov B. B. , 1999 : Measurement of humidity profiles in the atmosphere by the Global Positioning System and radar
profiling. COST Office, Brussels, Belgium, Final Rep., in press . Gossard, E. E. , Chadwick R. B. , Neff W. D. , and Moran K. P. , 1982 : The use of ground-based Doppler radars to measure gradients, fluxes, and structure parameters in elevated layers. J. Appl. Meteor. , 21 , 211 – 226 . 10.1175/1520-0450(1982)021<0211:TUOGBD>2.0.CO;2 Gossard, E. E. , Wolfe D. E. , and Stankov B. B. , 1999 : Measurement of humidity profiles in the atmosphere by the Global Positioning System and radar
th Int. Laser Radar Conf., NASA/CP-1998-207671/PT2, Annapolis, MD, NASA, 565–568 . Corcoran, R. , and Pronk R. , 2003 : POS MV model 320 V30 ethernet and SCSI ICD document No. PUBS-ICD-000033 Rev. 1.02. APPLANIX document, 140 pp. [Available from APPLANIX Corp, 85 Leek Crescent, Richmond Hill, ON L4B 3B3, Canada.] . Edson, J. , Hinton A. , Prada K. , Hare J. , and Fairall C. , 1998 : Direct covariance flux estimates from mobile platforms at sea. J. Atmos. Oceanic Technol. , 15
th Int. Laser Radar Conf., NASA/CP-1998-207671/PT2, Annapolis, MD, NASA, 565–568 . Corcoran, R. , and Pronk R. , 2003 : POS MV model 320 V30 ethernet and SCSI ICD document No. PUBS-ICD-000033 Rev. 1.02. APPLANIX document, 140 pp. [Available from APPLANIX Corp, 85 Leek Crescent, Richmond Hill, ON L4B 3B3, Canada.] . Edson, J. , Hinton A. , Prada K. , Hare J. , and Fairall C. , 1998 : Direct covariance flux estimates from mobile platforms at sea. J. Atmos. Oceanic Technol. , 15
value of T is used. 4. IPT application to simulated cases In this section we would like to show the accuracy improvements achieved by including the elevation scans for the retrieval of temperature profiles. This is done on the basis of a simulation study for clear-sky situations when the strongest temperature variations are expected due to strong radiative fluxes at the surface. L07 have performed an extensive accuracy assessment of the IPT within an NWP model domain using zenith measurements
value of T is used. 4. IPT application to simulated cases In this section we would like to show the accuracy improvements achieved by including the elevation scans for the retrieval of temperature profiles. This is done on the basis of a simulation study for clear-sky situations when the strongest temperature variations are expected due to strong radiative fluxes at the surface. L07 have performed an extensive accuracy assessment of the IPT within an NWP model domain using zenith measurements
.1127/0941-2948/2006/0101 Gossard, E. E. , and Strauch R. G. , 1983 : Radar Observation of Clear Air and Clouds . Elsevier, 280 pp . Gossard, E. E. , Chadwick R. R. , Neff W. D. , and Moran K. P. , 1982 : The use of ground based Doppler radars to measure gradients, fluxes, and structure parameters in elevated layers. J. Appl. Meteor. , 21 , 211 – 226 . 10.1175/1520-0450(1982)021<0211:TUOGBD>2.0.CO;2 Gossard, E. E. , Chadwick R. B. , Detman T. R. , and Gaynor J. , 1984 : Capability of surface
.1127/0941-2948/2006/0101 Gossard, E. E. , and Strauch R. G. , 1983 : Radar Observation of Clear Air and Clouds . Elsevier, 280 pp . Gossard, E. E. , Chadwick R. R. , Neff W. D. , and Moran K. P. , 1982 : The use of ground based Doppler radars to measure gradients, fluxes, and structure parameters in elevated layers. J. Appl. Meteor. , 21 , 211 – 226 . 10.1175/1520-0450(1982)021<0211:TUOGBD>2.0.CO;2 Gossard, E. E. , Chadwick R. B. , Detman T. R. , and Gaynor J. , 1984 : Capability of surface
