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  • 16th International Symposium for the Advancement of Boundary-Layer Remote Sensing (ISARS 2012) x
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C. R. Wood, R. D. Kouznetsov, R. Gierens, A. Nordbo, L. Järvi, M. A. Kallistratova, and J. Kukkonen

studies is to estimate sensible heat flux . Scintillometry is desirable because it gives a path average (most typically over some hundreds of meters) that is comparable to the scales typically used in meteorological modeling. Because of the spatial averaging, it is possible to obtain estimates of turbulence quantities over shorter time periods than is possible with the eddy-covariance (EC) method ( Aubinet et al. 2012 ). Yet, the most common way to examine the reliability of scintillometer data is to

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Rostislav Kouznetsov, Priit Tisler, Timo Palo, and Timo Vihma

turbulent fluxes were calculated in streamwise coordinates obtained with the double-rotation method (see, e.g., Rebmann et al. 2012 ). The momentum flux was calculated as a component of the Reynolds stress in the direction of the mean velocity vector. No corrections for the effect of humidity fluxes were applied in this study. We estimated them to be less than about 15%, which we consider to be insignificant for the qualitative consideration below. b. Sodar We used the 3-component Doppler sodar “Latan

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B. Van Dam, D. Helmig, W. Neff, and L. Kramer

conditions at SP when compared with sodar measurements. This model was tested against sodar measurements more recently at SP using vertical temperature gradients from a 22-m tower and rawinsonde temperature profiles. It was found that model results were representative of the BLD during very stable conditions but were overestimates in other cases. In this expression, H is only weakly dependent on vertical static stability. The Pollard et al. (1973) model assumes a sensible heat flux H s = ρc p of

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Jacob Berg, Jakob Mann, and Edward G. Patton

because of the relatively weak influence of the Coriolis force here. In addition, the streamwise vertical momentum flux is controlled by wind shear in agreement with the turbulent-viscosity hypothesis ( Pope 2000 ): where the turbulent eddy viscosity is given by ν T . We have used the normal micrometeorological coordinate system convention that x is aligned with the near-surface mean wind direction—that is, U ( z ) is the mean wind with superimposed fluctuations u ′( x , y , z , t ), and

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A. B. White, M. L. Anderson, M. D. Dettinger, F. M. Ralph, A. Hinojosa, D. R. Cayan, R. K. Hartman, D. W. Reynolds, L. E. Johnson, T. L. Schneider, R. Cifelli, Z. Toth, S. I. Gutman, C. W. King, F. Gehrke, P. E. Johnston, C. Walls, D. Mann, D. J. Gottas, and T. Coleman

the surface can often be blocked by the terrain ( Neiman et al. 2002 ). Combining the winds in the low-level jet with the measured IWV, used as a proxy for the low-level moisture, allows the calculation of the bulk flux of water vapor, which Neiman et al. (2009) showed to be more highly correlated with orographic rainfall than either the winds in the low-level jet core or the IWV, treated separately. Figure 7 illustrates the scientific concepts behind the ARO development. Fig . 7. Schematic of

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Qing Yang, Larry K. Berg, Mikhail Pekour, Jerome D. Fast, Rob K. Newsom, Mark Stoelinga, and Catherine Finley

boundary layer (PBL) parameterizations play an important role in simulating low-level winds and PBL structures ( Berg and Zhong 2005 ; Shin and Hong 2011 ) and are used to parameterize subgrid vertical fluxes of momentum, heat, and moisture. Three PBL parameterization schemes have been selected to test the sensitivity of the WRF model's performance to the choice of PBL schemes: Mellor–Yamada–Janjić (MYJ; Janjić 1994 ), University of Washington (UW; Bretherton and Park 2009 ), and Yonsei University

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Valery F. Kramar, Evgeniya Baykova, Margarita Kallistratova, Rostislav Kouznetsov, and Sergei Kulichkov

structure, large convective structures in the shape of a toroid have been observed by a sodar network in the Kalmykian desert ( Granberg et al. 2009 ; Kalmykia is part of the Russian Federation), which is an area of higher heat flux than Moscow; nevertheless, we expect the convective structures in Moscow to be toroidal. In the ideal case, a database with the characteristics of pollutant sources should be made to provide necessary input for models of short-range transfer of pollutants in a city air basin

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Margarita A. Kallistratova, Rostislav D. Kouznetsov, Valerii F. Kramar, and Dmitrii D. Kuznetsov

low-level jet characteristics measured by sodars over rural and urban areas . Meteor. Z. , 18 , 289 – 295 , doi:10.1127/0941-2948/2009/0380 . Karipot, A. , Leclerc M. Y. , Zhang G. , Lewin K. F. , Nagy J. , Hendrey G. R. , and Starr G. , 2008 : Influence of nocturnal low-level jet on turbulence structure and CO 2 flux measurements over a forest canopy. J. Geophys. Res., 113, D10102 , doi:10.1029/2007JD009149 . Kouznetsov, R. D. , Kramar V. F. , and Kallistratova M. A

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Mikael Sjöholm, Nikolas Angelou, Per Hansen, Kasper Hjorth Hansen, Torben Mikkelsen, Steinar Haga, Jon Arne Silgjerd, and Neil Starsmore

or by introducing a quadrature detection scheme ( Hogenboom and DiMarzio 1998 ), which can provide the sign of the line-of-sight velocity without the use of an acousto-optic modulator. Combining the flow field measurement capabilities of the WindScanner technology with the concentration mapping capabilities provided by scanning aerosol and differential absorption lidars could constitute a fruitful combination for detailed studies of rotorcraft-downwash-generated brownout as well as remote flux

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Elías Lau, Scott McLaughlin, Frank Pratte, Bob Weber, David Merritt, Maikel Wise, Gary Zimmerman, Matthew James, and Megan Sloan

height ( Hashiguchi et al. 1995 ; Cohn and Angevine 2000 ), cold front characterization ( Browning et al. 1998 ), heat and momentum fluxes ( Angevine et al. 1993 ), classification of precipitating clouds ( Williams et al. 1995 ), and rainfall drop size distributions ( Schafer et al. 2002 ). Operational applications include weather forecasting, air quality forecasting for urban areas, and wind shear determination at airports. Typical BL RWPs currently deployed utilize antenna arrays, either several

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