ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-8-7281-2008 Continuous monitoring of the boundary-layer top with lidar Baars H. 1 Ansmann A. 1 Engelmann R. 1 Althausen D. 1 Leibniz Institute for Tropospheric Research, Leipzig, Germany 10 12 2008 8 23 7281 7296 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/8/7281/2008/acp-8-7281-2008.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/8/7281/2008/acp-8-7281-2008.pdf

Continuous lidar observations of the top height of the boundary layer (BL top) have been performed at Leipzig (51.3° N, 12.4° E), Germany, since August 2005. The results of measurements taken with a compact, automated Raman lidar over a one–year period (February 2006 to January 2007) are presented. Main goals of the study are (a) to demonstrate that BL top monitoring with lidar throughout the year is possible, (b) to present the required data analysis method that permits an automated, robust retrieval of BL top at all weather situations, and (c) to use this opportunity to compare the lidar-derived BL top data with respective BL tops hourly predicted by the regional weather forecast model COSMO. Four different lidar methods for the determination of the BL top are discussed. The wavelet covariance algorithm is modified so that an automated retrieval of BL depths from lidar data is possible. Three case studies of simultaneous observations with the Raman lidar, a vertical-wind Doppler lidar, and accompanying radiosonde profiling of temperature and humidity are presented to compare the potential and the limits of the four lidar techniques. The statistical analysis of the one-year data set reveals that the seasonal mean of the daytime (about 08:00–20:00 Local Time, LT) maximum BL top is 1400 m in spring, 1800 m in summer, 1200 m in autumn, and 800 m in winter at the continental, central European site. BL top typically increases by 100–300 m per hour in the morning of convective days. The comparison between the lidar-derived BL top heights and the predictions of COSMO yields a general underestimation of the BL top by about 20% by the model.

 References Althausen, D., Engelmann, R., Foster, R., Rhone, P., and Baars, H.: Portable Raman lidar for determination of particle backscatter and extinction coefficients, in: Reviewed and revised papers presented at the 22nd ILRC, ESA SP–561, Volume 1, edited by: Pappalardo, G. and Amodeo, A., 83–86, ESA Publications Division, ESTEC, Noordwijk, The Netherlands, 2004. Althausen, D., Engelmann, R., Baars, H., Heese, B., and Komppula, M.: Portable Raman lidar Polly$^\rm XT$ for automatic profile measurements of aerosol backscatter and extinction coefficient, in: Proceedings, 24th ILRC, edited by: Hardesty, M. and Mayor, S., 45–48, NCAR, Boulder, CO, 2008. Ansmann, A. and Müller, D.: Lidar – Range-Resolved Optical Remote Sensing of the Atmosphere, chap. Lidar and atmospheric aerosol particles, Springer, New York, 2005. Ansmann, A., Wandinger, U., Riebesell, M., Weitkamp, C., and Michaelis, W.: Independent measurement of extinction and backscatter profiles in cirrus clouds by using a combined Raman elastic-backscatter lidar, Appl. Opt., 31, 7113–7131, 1992. Ansmann, A., Engelmann, R., Althausen, D., Wandinger, U., Hu, M., Zhang, Y., and He, Q.: High aerosol load over the Pearl River Delta, South China, observed with Raman lidar and Sun photometer, Geophys. Res. Lett., 32, L13815, doi:10.1029/2005GL023094, 2005. Beyrich, F.: Mixing height estimation from sodar data – a critcal discussion, Atmos. Environ., 31, 3941–3953, 1997. Brooks, I.: Finding Boundary Layer Top: Application of a wavelet covariance transform to lidar backscatter profiles, J. Atmos. Ocean. Tech., 20, 1092–1105, 2003. Campbell, J R., Hlavka, D L., Welton, E J., Flynn, C J., Turner, D D., Spinhirne, J D., Scott, V S., and Hwang, I H.: Full-time, eye-safe cloud and aerosol lidar observations at Atmospheric Radiation Measurement program sites: instruments and data processing., J. Atmos. Ocean. Tech., 19, 431–442, 2002. 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. Emeis, S., Münkel, C., Vogt, S., Müller, W., and Schäfer, K.: Atmospheric boundary-layer structure from simultaneous SODAR, RASS, and ceilometer measurements, Atmos. Environ., 38, 273–286, 2004. Engelmann, R., Wandinger, U., Ansmann, A., Müller, D., Zeromskis, E., Althausen, D., and Wehner, B.: Lidar observations of the vertical aerosol flux in the planetary boundary layer, J. Atmos. Ocean. Tech., 25, 1296–1306, 2008. Fay, B.: Evaluation and intercomparison of mixing heights derived from a Richardson number scheme and other MH formulae using operational NWP models at the German Weather Service, in: 5th International Conference on Harmonisation within Atmospheric Dispersion Modelling, Rhodes, 18–21 May 1998. Fay, B. and Neunhäuserer, L.: Evaluation of high-resolution forecasts with the non-hydrostaticnumerical weather prediction model Lokalmodell for urban air pollution episodes in Helsinki, Oslo and Valencia, Atmos. Chem. Phys., 6, 2107–2128, 2006. Fay, B., Schrodin, R., Jacobsen, I., and Engelbart, D.: Validation of mixing heights derived from the operational NWP models at the German Weather Service, in: The Determination of the Mixing Height – Current Progress and Problems, EURASAP Workshop Proceedings, 1–3 October 1997, Ris\o~National Laboratory, edited by: Gryning, S., Beyrich, F., and Batchvarova, E., 55–58, 1997. Flamant, C., Pelon, J., Flamant, P., and Durand, P.: Lidar determination of the entrainment zone thickness at the top of the unstable marine atmospheric boundary layer, Bound.-Lay. Meteorol., 83, 247–284, 1997. Hooper, W P. and Eloranta, E W.: Lidar measurements of wind in the planetary boundary layer: the method, accuracy, and results from joint measurements with radiosonde and kytoon, J. Clim. Appl. Meteorol., 25, 990–1001, 1986. Lammert, A. and Bösenberg, J.: Determination of the convective boundary-layer height with laser remote sensing, Bound.-Lay. Meteorol., 119, 157–170, 2005. Liu, Z., Vaughan, M A., Winker, D M., Hostetler, C A., Poole, L R., Hlavka, D., Hart, W., and McGill, M.: Use of probability distribution functions for discriminating between cloud and aerosol in lidar backscatter data, J. Geophys. Res., 109, D15202, doi:10.1029/2004JD004732, 2004. Martucci, G., Matthey, R., Mitev, V., and Richner, H.: Comparison between backscatter lidar and radiosonde measurements of the diurnal and nocturnal stratification in the lower troposphere, J. Atmos. Ocean. Tech., 24, 1231–1244, 2007. Mattis, I., Müller, D., Ansmann, A., Wandinger, U., Preißler, J., Seifert, P., and Tesche, M.: Ten years of multiwavelength Raman lidar observations of free-tropospheric aerosol layers over central Europe: Geometrical properties and annual cycle, J. Geophys. Res., 113, D20202 doi:10.1029/2007JD009636, 2008. Menut, L., Flamant, C., Pelon, J., and Flamant, P H.: Urban boundary-layer height determination from lidar measurements over the Paris area, Appl. Opt., 38, 945–954, 1999. Morille, Y., Haeffelin, M., Drobinski, P., and Pelon, J.: STRAT: an automated algorithm to retrieve the vertical structure of the atmosphere from single–channel lidar data, J. Atmos. Ocean. Tech., 24, 761–775, 2007. Müller, D., Tesche, M., Eichler, H., Engelmann, R., Althausen, D., Ansmann, A., Cheng, Y F., Zhang, Y., and Hu, M.: Strong particle absorption over the Pearl River Delta (south China) and Beijing (north China) determined from combined Raman lidar and Sun photometer observations, Geophys. Res. Lett., 33, L20811, doi:10.1029/2006GL027196, 2006. Müller, D., Ansmann, A., Mattis, I., Tesche, M., Wandinger, U., Althausen, D., and Pisani, G.: Aerosol-type-dependent lidar-ratios observed with Raman lidar, J. Geophys. Res., 112, D16202, doi:10.1029/2006JD008292, 2007. Piironen, A K. and Eloranta, E W.: Convective boundary layer depths and cloud geometrical properties obtained from volume imaging lidar data, J. Geophys. Res., 100, 569–576, 1995. Russel, P., Uthe, E., Ludwig, F., and Shaw, N.: A comparison of atmospheric structure as observed with monostatic acoustic sounder and lidar techniques, J. Geophys. Res., 79, 5555–5566, 1974. Seibert, P., Beyrich, F., Gryning, S.-E., Joffre, S., Rassmussen, A., and Tercier, P.: Review and intercomparison of operational methods for the determination of the mixing height, Atmos. Environ., 34, 1001–1027, 2000. Steeneveld, G J., van~de Wiel, B J., and Holtslag, A. A M.: Diagnostic equations for the stable boundary layer height: evaluation and dimensional analysis, J. Appl. Meteorol. Clim., 46, 212–225, 2007. Steyn, D., Baldi, M., and Hoff, R M.: The detection of mixed layer depth and entrainment zone thickness from lidar backscatter profiles, J. Atmos. Ocean. Tech., 16, 953–959, 1999. Stull, R B.: An Introduction to Boundary Layer Meteorology, Kluwer Academic Publishers, Dordrecht/Boston/London, 1988. Tesche, M., Ansmann, A., Müller, D., Althausen, D., Engelmann, R., Hu, M., and Zhang, Y.: Particle backscatter, extinction, and lidar ratio profiling with Raman lidar in south and north China, Appl. Opt., 46, 6302–6308, 2007. Turner, D D., Ferrare, R A., Heilman~Brasseur, L A., Feltz, W F., and Tooman, T P.: Automated retrievals of water vapor and aerosol profiles from an operational Raman lidar, J. Atmos. Ocean. Technol., 19, 37–50, 2002. Vogelezang, D. H P. and Holtslag, A. A M.: Evaluation and model impacts of alternative boundary–layer height formulations, Bound.-Lay. Meteorol., 81, 245–269, 1996. Wandinger, U. and Ansmann, A.: Experimental determination of the lidar overlap profile with Raman lidar, Appl. Opt., 41, 511–514, 2002. Wiegner, M., Emeis, S., Freudenthaler, V., Heese, B., Junkermann, W., Münkel, C., Schäfer, K., Seefeldner, M., and Vogt, S.: Mixing layer height over Munich, Germany: variability and comparisions of different methodologies, J. Geophys. Res., 111, D13201, doi:10.1029/2005JD006593, 2006. Zeromskis, E., Wandinger, U., Althausen, D., Engelmann, R., Rhone, P., and Foster, R.: Coherent Doppler lidar for wind profiling in the lower atmosphere, in: Extended Abstracts, Sixth International Symposium on Tropospheric Profiling: Needs and Technologies, edited by: Wandinger, U., 71–73, Leibniz Institute for Tropospheric Research, Leipzig, Germany, 2003. Zilitinkevich, S. and Baklanov, A.: Calculation of the height of the stable boundary layer in practical applications, Bound.-Lay. Meteorol., 105, 389–409, 2002.