References

ANGEO

Annales Geophysicae

ANGEO

Ann. Geophys.

1432-0576

Copernicus Publications

Göttingen, Germany

10.5194/angeo-28-825-2010

Elastic-backscatter-lidar-based characterization of the convective boundary layer and investigation of related statistics

Pal

¹ Behrendt

¹ Wulfmeyer

Institute of Physics and Meteorology (IPM), University of Hohenheim, Garbenstrasse 30, 70599 Stuttgart, Germany

22 03 2010

28 3 825 847

2010

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

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We applied a ground-based vertically-pointing aerosol lidar to investigate the evolution of the instantaneous atmospheric boundary layer depth, its growth rate, associated entrainment processes, and turbulence characteristics. We used lidar measurements with range resolution of 3 m and time resolution of up to 0.033 s obtained in the course of a sunny day (26 June 2004) over an urban valley (central Stuttgart, 48°47' N, 9°12' E, 240 m above sea level). The lidar system uses a wavelength of 1064 nm and has a power-aperture product of 2.1 W m2. Three techniques are examined for determining the instantaneous convective boundary layer (CBL) depth from the high-resolution lidar measurements: the logarithm gradient method, the inflection point method, and the Haar wavelet transform method. The Haar wavelet-based approach is found to be the most robust technique for the automated detection of the CBL depth. Two different regimes of the CBL are discussed in detail: a quasi-stationary CBL in the afternoon and a CBL with rapid growth during morning transition in the presence of dust layers atop. Two different growth rates were found: 3–5 m/min for the growing CBL in the morning and 0.5–2 m/min during the quasi-steady regime. The mean entrainment zone thickness for the quasi-steady CBL was found to be ~75 m while the CBL top during the entire day varied between 0.7 km and 2.3 km. A fast Fourier-transform-based spectral analysis of the instantaneous CBL depth time series gave a spectral exponent value of 1.50±0.04, confirming non-stationary CBL behavior in the morning while for the other regime a value of 1.00±0.06 was obtained indicating a quasi-stationary state of the CBL. Assuming that the spatio-temporal variation of the particle backscatter cross-section of the aerosols in the scattering volume is due to number density fluctuations (negligible hygroscopic growth), the particle backscatter coefficient profiles can be used to investigate boundary layer turbulence since the aerosols act as tracers. We demonstrate that with our lidar measurements, vertical profiles of variance, skewness, and kurtosis of the fluctuations of the particle backscatter coefficient can be determined. The variance spectra at different altitudes inside the quasi-steady CBL showed an f−5/3 dependency. The integral scale varied from 40 to 90 s (depending on height), which was significantly larger than the temporal resolution of the lidar data. Thus, the major part of the inertial subrange was detected and turbulent fluctuations could be resolved. For the quasi-stationary case, negative values of skewness were found inside the CBL while positive values were observed in the entrainment zone near the top of the CBL. For the case of the rapidly growing CBL, the skewness profile showed both positive and negative values even inside the CBL.

References 1

Angevine, W. M., White, A. B., and Avery, S. K.: Boundary layer depth and entrainment zone characterization with a boundary layer wind profiler, Bound.-Layer Meteorol., 68, 375–385, 1994.

Baars, H., Ansmann, A., Engelmann, R., and Althausen, D.: Continuous monitoring of the boundary-layer top with lidar, Atmos. Chem. Phys., 8, 7281–7296, 2008.

Behrendt, A., Wagner, G., Petrova, A., Schiler, M., Pal, S., Schaberl, T., and Wulfmeyer, V.: Modular lidar systems for high-resolution 4-dimensional measurements of water vapor, temperature, and aerosols, in: Lidar Remote Sensing for Industry and Environment Monitoring V, Proceedings of SPIE, edited by: Singh, U. N. and Kohei Mizutani, 5653, Honolulu, Hawaii, USA, 8–12 November 2004, 220–227, 2005.

Behrendt, A.: Temperature Measurements with Lidar, in: Lidar: Range-Resolved Optical Remote Sensing of the Atmosphere, edited by: Weitkamp, C., Springer Series in Optical Sciences, vol. 102, ISBN: 0-387-40075-3, Springer, New York, 273–305, 2005.

Beyrich, F. and Gryning, S.: Estimation of the entrainment zone depth in a shallow convective boundary layer from sodar data, J. Appl. Meteorol., 37, 255–268, 1998.

Boers, R., Eloranta, E. W., and Coulter, R. L.: Lidar observations of mixed layer dynamics: Tests of parameterized entrainment models of mixed layer growth rate, J. Appl. Meteorol., 23, 247–266, 1984.

Boers, R., Melfi, S. H., and Palm, S. P.: Fractal nature of the planetary boundary layer depth in the trade wind cumulus regime, Geophys. Res. Lett., 22(13), 1705–1708, 1995.

Boheren, C. and Huffmann, D.: Absorption and scattering of light by small particles, Wiley, New York, 530, 1983.

Brooks, I. M.: Finding boundary layer top: Application of a wavelet covariance transform to lidar backscatter profiles, J. Atmos. Ocean. Technol., 20, 1092–1105, 2003.

Cai, X.-M.: Dispersion of a passive plume in an idealized urban convective boundary layer: A large-eddy simulation, Atmos. Environ., 34, 61–72, 2000.

Chemel, C. and Staquet, C.: A formulation of convective entrainment in terms of mixing efficiency, J. Fluid. Mech., 580, 169–178, 2007.

Cohn, S. A. and Angevine, W. M.: Boundary layer height and entrainment zone thickness measured by lidars and wind-profiling radars, J. Appl. Meteorol., 39, 1233–1247, 2000.

Couvreux, F., Guichard, F., Redelsperger, J. L., Kiemle, C., Masson, V., Lafore, J. P., and Flamant, C.: Water-vapor variability within a convective boundary-layer assessed by large-eddy simulations and IHOP_2002 observations, Q. J. Roy. Meteorol. Soc., 131, 2665–2693, 2005.

Couvreux, F., Guichard, F., Masson, V., and Redelsperger, J.-L.: Negative water vapour skewness and dry tongues in the convective boundary layer: observations and large-eddy simulation budget analysis, Bound.-Lay. Meteorol., 123, 269–294, 2007.

Daubechies, I., Mallat, S., and Willsky, A.: Introduction to the special issue on wavelet transforms and multiresolution signal analysis, IEEE Trans. Inf. Theory., 38(2), 528–531, 1992.

Davis, A., Marshak, A., Wiscombe, W., and Cahalan, R.: Multifractal characterizations of nonstationarity and intermittency in geophysical fields: Observed, retrieved, or simulated, J. Geophys. Res., 99, 8055–8072, 1994.

Davis, K. J., Lenschow, D. H., Oncley, S. P., Kiemle, C., Ehret, G., and Giez, A.: Role of entrainment in surface–atmosphere interactions over a boreal forest, J. Geophys. Res., 102(29), 29218–29230, 1997.

Davis, K. J.,~Gamage, N., Hagelberg, C. R., Kiemle, C., Lenschow, D. H., and Sullivan,~P. P.: An objective method for deriving atmospheric structure from airborne lidar observations, J. Atmos. Ocean. Technol., 17, 1455–1468, 2000.

Deardorff, J. W., Willis, G. E., and Lilly, D. K.: Laboratory investigation of nonsteady penetrative convection, J. Fluid Mech., 35, 7–31, 1969.

Deardorff, J. W.: Numerical investigation of neutral and unstable planetary boundary layers, J. Atmos. Sci., 29, 91–115, 1972.

Degrazia, G. A., Anfossi, D., Carvalho, J. C., Mangia, C., Tirabassi, T., and Campos Velho, H. F.: Turbulence parameterization for PBL dispersion models in all stability conditions, Atmos. Environ., 34, 3575–3583, 2000.

Engelmann, R., Wandinger, U., Ansmann, A., Müller, D., Žeromskis, E., Althausen, D., and Wehner, B.: Lidar observations of the aerosol vertical flux in the planetary boundary layer, J. Atmos. Ocean. Technol., 25(8), 1296–1306, 2008.

Fitzgerald, J. W.: Approximation formulas for the equilibrium size of an aerosol particle as a function of its dry size and composition and ambient relative humidity, J. Appl. Meteorol., 14, 1044–1049, 1975.

Flamant, C., Pelon, J., Flamant, P. H., and Durand, P.: Lidar determination of the entrainment zone thickness at the top of the unstable marine boundary layer, Bound.-Lay. Meteorol., 83, 247–284, 1997.

Gamage, N. and Hagelberg, C.: Detection and analysis of micro fronts and associated coherent events using localized transforms, J. Atmos. Sci., 50, 750–756, 1993.

Gibert, F., Cuesta, J., Yano, J.-I., Arnault, N., and Flamant, P. H.: On the correlation between convective plume updrafts, lidar reflectivity and depolarization ratio, Bound.-Lay. Meteorol., 125, 553–573, 2007.

Hänel, G.: The properties of atmospheric aerosol particles as functions of relative humidity at thermodynamic equilibrium with the surrounding moist air, Adv. Geophys., 19, 73–188, 1976.

He, Q. S., Mao, J. T., Chen, J. Y., and Hu, Y. Y.: Observational and modeling studies of urban atmospheric boundary-layer height and its evolution mechanisms, Atmos. Environ., 40, 1064–1077, 2006.

Kiemle, C., Ehret, G., Giez, A., Davis, K. J., Lenschow, D. H., and Oncley, S. P.: Estimation of boundary layer humidity fluxes and statistics from airborne differential absorption lidar (DIAL), J. Geophys Res., 102(D24), 29189–29203, 1997.

Kolmogorov, A. N.: The local structure of turbulence in incompressible viscous fluid for very large Reynolds numbers', Dokalady, ANSSSR 30, 301–304, 1941.

Lammert, A. and Bösenberg, J.: Determination of the convective boundary layer height with laser remote sensing, Bound.-Lay. Meteorol., 119, 159–170, 2006.

Larson, V. E., Wood, R., Field, P. R., Golaz, J. C., Vonder Haar, T. H., and Cotton, W. R.: Small-scale and mesoscale variability of scalars in cloudy boundary layers: one-dimensional probability density functions, J. Atmos. Sci., 58, 1978–1994, 2001.

Lenschow, D. H., Wulfmeyer, V., and Senff, C.: Measuring second-through fourth-order moments in noisy data, J. Atmos. Ocean. Technol., 17, 1330–1347, 2000.

Lothon, M., Lenschow, D. H., and Mayor, S. D.: Coherence and scale of vertical velocity in the convective boundary layer from a Doppler lidar, Bound.-Lay. Meteorol., 121, 521–536, 2006.

Martucci, G., Matthey, R., and Mitev, V.: Comparison between backscatter lidar and radiosonde measurements of the diurnal and nocturnal stratification in the lower troposphere, J. Atmos. Ocean. Technol., 24, 1231–1244, 2007.

Mahrt, L.: Boundary layer moisture regimes, Q. J. Roy. Meteorol. Soc., 117, 151–176, 1991.

Melfi, S. H., Spinhirne, J. D., Chou, S. H., and Palm, S. P.: Lidar observations of vertically organized convection in the planetary boundary layer over the ocean, J. Climate Appl. Meteorol., 24, 806–821, 1985.

Menut, L., Flamant, C., Pelon, J., and Flamant, P. H.: Urban boundary-layer height determination from lidar measurements over the Paris area, Appl. Optics, 38, 945–954, 1999.

Moeng, C. H. and Wyngaard, J. C.: Statistics of conservative scalars in the convective boundary layer, J. Atmos. Sci., 41, 3161–3169, 1984.

Pal, S., Behrendt, A., Radlach, M., Schaberl, T., and Wulfmeyer, V.: Eye safe scanning aerosol lidar at 355 nm, Reviewed and Revised Papers of the 23rd International Laser Radar Conference (ILRC), Nara, Japan, 23–27~July 2006.

Pal, S., Behrendt, A., Wulfmeyer, V. , Valdebenito, Á. M., and Lammel, G.: A novel approach for the characterisation of transport and optical properties of aerosol particles emitted from an animal facility – Part I: Detection and analyses of aerosol plumes using a scanning eye-safe elastic UV lidar, Atmos. Environ., submitted, 2010.

Pelletier, J. D.: Kardar-Parisi-Zhang scaling of the height of the convective boundary layer and multifarctal structure of cumulus cloud fields, Phys. Rev. Lett., 78(13), 2672–2675, 1997.

Perera, M. J. A. M., Fernando, J. S., and Boyer, D. L.: Turbulent mixing at an inversion layer, J. Fluid Mech., 267, 275–298, 1994.

Radlach, M., Behrendt, A., and Wulfmeyer, V.: Scanning rotational Raman lidar at 355 nm for the measurement of tropospheric temperature fields, Atmos. Chem. Phys., 8, 159–169, 2008.

Randriamiarisoa, H., Chazette, P., Couvert, P., Sanak, J., and Mégie, G.: Relative humidity impact on aerosol parameters in a Paris suburban area, Atmos. Chem. Phys., 6, 1389–1407, 2006.

Russell, P. B., Uthe, E. E., Ludwig, F. L., and Shaw, N. A.: A comparison of atmospheric structure as observed with monostatic acoustic sounder and lidar techniques, J. Geophys. Res., 79, 5555–5566, 1974.

Schwemmer, G. K., Miller, D. O., Wilkerson, T. D., and Lee, S.: Lidar data products and applications enabled by conical scanning, edited by: Pappalardo, G. and Amodo, A., Reviewed and revised papers presented at 22nd International Laser Radar Conference, Matera, Italy, 12–16 July 2004, European Space Agency (SP-561), 17–20, 2004.

Seibert, P., Beyrich, F., Gryning, S.-E., Joffre, S., Rasmussen, A., and Tercier, P.: Review and intercomparison of operational methods for the determination of mixing height, Atmos. Environ., 34, 1001–1027, 2000.

Senff, C. J., Bösenberg, J., and Peters, G.: Measurement of water vapor flux profiles in the convective boundary layer with lidar and Radar-RASS, J. Atmos. Ocean. Technol., 11, 85–93, 1994.

Senff, C. J., Bösenberg, J., Peters, G., and Schaberl, T.: Remote sensing of turbulent ozone fluxes and the ozone budget in the convective boundary layer with DIAL and radar-RASS: A case study, Contrib. Atmos. Phys., 69, 161–176, 1996.

Senff, C. J., Banta, R. M., Darby, L. S., Alvarez, R. J., Sandberg, S. P., Hardesty, R. M., and Angevine, W. M.: Ozone distribution and transport in the Houston area: Insights gained by airborne lidar, Proceedings of AGU Fall Meeting, San Francisco, California, USA, 6–10 December 2002, 173 p., 2002.

Sicard, M., Perez, C., Rocadenbosch, F., Baldasano, J. M., and Garcia-Vizcaino, D.: Mixed-layer depth determination in the Barcelona coastal area from regular lidar measurements: Methods, results and limitations, Bound.-Lay. Meteorol., 119, 135–157, 2006.

Sorbjan, Z.: Similarity scales and universal profiles of statistical moments in the convective boundary layer, J. Appl. Meteorol., 29, 762–775, 1990.

Sorbjan, Z.: Effects caused by varying the strength of the capping inversion based on a large eddy simulation model of the shear-free convective boundary layer, J. Atmos. Sci., 53, 101–112, 1996.

Stull, R. B.: An Introduction to Boundary Layer Meteorology, Kluwer Acad. Publ., Dordrecht, 666, 1988.

Stull, R. B. and Eloranta, E. W.: Boundary layer experiment, B. Am. Meteorol. Soc., 65, 450–456, 1984.

Sullivan, P. P., Moeng, C. H., Stevens, B., Lenschow, D. H., and Mayor, S. D.: Structure of the entrainment zone capping the convective atmospheric boundary layer, J. Atmos. Sci., 55, 3042–3064, 1998.

Taylor, G. I.: Diffusion by Continuous Movements, Proc. London Math. Soc., 20, 196, 1921.

Ulke, A. G.: New turbulent parameterization for a dispersion model in the atmospheric boundary layer, Atmos. Environ., 34, 1029–1042, 2000.

Wulfmeyer, V.: Investigation of turbulent processes in the lower troposphere with water-vapor DIAL and radar-RASS, J. Atmos. Sci., 56, 1055–1076, 1999a.

Wulfmeyer, V.: Investigations of humidity skewness and variance profiles in the convective boundary layer and comparison of the latter with large eddy simulation results, J. Atmos. Sci., 56, 1077–1087, 1999b.

Wulfmeyer, V. and Feingold, G.: On the relationship between relative humidity and particle backscattering coefficient in the marine boundary layer determined with differential absorption lidar, J. Geophys. Res., 105(D4), 4729–4741, 2000.

Wulfmeyer, V. and Janjić, T.: 24-h observations of the marine boundary layer using ship-borne NOAA high-resolution doppler lidar, J. Appl. Meteorol., 44, 1723–1744, 2005.

Wulfmeyer, V., Behrendt, A., Bauer, H.-S., Kottmeier, C., et al.: The Convective and Orographically-induced Precipitation Study: A Research and Development Project of the World Weather Research Program for improving quantitative precipitation forecasting in low-mountain regions, B. Am. Meteorol. Soc., 89(10), 1477–1486, 2008.

Wulfmeyer, V., Turner, D. D., Pal, S., and Wagner, E.: Can the water-vapor Raman lidar resolve profiles of turbulent variables in the convective boundary layer?, Bound.-Lay. Meteorol., submitted, 2010.

Wyngaard, J. C. and Brost, R. A.: Top-down and bottom-up diffusion of a scalar in the convective boundary layer, J. Atmos. Sci., 41, 102–112, 1984.