Abstract
Measurements in the atmospheric surface layer are generally made with point sensors located in the first few tens of metres. In most cases, however, these measurements are not representative of the whole surface layer. Standard Doppler sodars allow a continuous display of the turbulent thermal structure and wind profiles in the boundary layer up to 1000 m, with a few points, if any, in the surface layer. To overcome these limitations a new sodar configuration is proposed that allows for a higher resolution in the surface layer. Because of its capabilities (echo recording starting at 2 m, echo intensity vertical resolution of approximately 2 m, temporal resolution of 1 s) this sodar is called the surface-layer mini-sodar (SLM-sodar). Features and capabilities of the SLM-sodar are described and compared with the sodar. The comparison of the thermal vertical structure given by the SLM-sodar and the sodar provides evidence that, in most cases, the surface layer presents a level of complexity comparable to that of the entire boundary layer. Considering its high vertical resolution, the SLM-sodar is a promising system for the study of the nocturnal surface layer. The nocturnal SLM-sodar measurements have shown that, depending on wind speed, the structure of the surface layer may change substantially within a short time period. At night, when the wind speed is greater than 3 m s−1, mechanical mixing destroys the wavy structure present in the nocturnal layer. Sonic anemometer measurements have shown that, in such cases, also the sensible heat flux varies with height, reaching a peak in correspondence with the wind speed peak. Under these conditions the assumption of horizontal homogeneity of the surface layer and the choice of the averaging time need to be carefully treated.
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References
Asimakopoulos DN, Helmis CG, Stephanou GJ (1987) Atmospheric acoustic minisounder. J Atmos Ocean Technol 4: 345–347
Bonner CS, Ashley MCB, Lawrence JS, Luong-Van DM, Storey JWV (2009) Snodar: an acoustic radar for atmospheric turbulence profiling with 1 m resolution. Acoust Aust 37: 47–51
Contini D, Mastrantonio G, Viola A, Argentini S (2004) Mean vertical motions in the PBL measured by Doppler sodar: accuracy, ambiguities, possible improvements. J Atmos Ocean Technol 21: 1532–1544
Contini D, Donateo A, Belosi F (2006) Accuracy of measurements of turbulent phenomena in the surface-layer with an ultrasonic anemometer. J Atmos Ocean Technol 23: 785–801
Contini D, Grasso F, Mastrantonio G, Viola AP, Martano P (2007) Performances of a modular PC-based multi-tone sodar system in measuring vertical wind velocity. Meteorol Z 16: 357–365
Derbyshire SH (1995) Stable boundary layers: observations, models, and variability. Part I: Modelling and measurements. Boundary-Layer Meteorol 74: 19–54
Gryning SE (1985) The Oresund experiment—a nordic mesoscale dispersion experiment over a land–water–land area. Bull Am Meteorol Soc 66: 1403–1407
Kaimal JC, Finnigan JJ (1994) Atmospheric boundary layer flow: their structure and measurement. Oxford University Press, New York, 289 pp
Kouznetsov RD (2009) The summertime ABL structure over an Antarctic oasis with a vertical Doppler sodar. Meteorol Z 18: 163–167
Lee X, Massman W, Law B (2004) Handbook of micrometeorology: a guide for surface flux measurement and analysis. Kluwer Academic Publishers, New York, 250 pp
Mastrantonio G, Argentini S (1997) A modular PC-based multiband sodar system. In: Singal SP (eds) Acoustic sounding and applications. Narosa Publishing House, New Delhi, pp 105–116
Mastrantonio G, Fiocco G (1982) Accuracy of wind velocity determinations with Doppler sodar. J Appl Meteorol 21: 820–830
McNider RT, England DE, Friedman MJ, Shi X (1995) Predictability of the stable atmospheric boundary layer. J Atmos Sci 20: 331–336
Mursch-Radlgruber E, Wolfe DE, Gregg DW, King CW, Neff WD, Sharp KAH, Ruffieux D (1994) NOAA’s portable, high-frequency mini-sodar design and first results. Int J Remote Sens 15: 325–332
Poulos GS, Bossert JE (1995) An observational and prognostic numerical investigation of complex terrain dispersion. J Appl Meteorol 34: 650–669
Seaman NL (2000) Meteorological modelling for air-quality assessment. Atmos Environ 34: 2231–2259
Weill A, Klapisz C, Baudin F (1986) The CRPE mini-sodar: applications in micrometeorology and in physics of precipitations. Atmos Res 20: 317–333
Acknowledgments
The authors are grateful to Dr. D. Contini for having made available the sonic anemometer measurements. Thanks go to Sigs. A. Conidi and F. Grasso for the help given during the field experiment. The authors also want to thank the anonymous reviewers and Dr. D. Cavallaro who helped improve the quality of the article.
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Open Access This is an open access article distributed under the terms of the Creative Commons Attribution Noncommercial License (https://creativecommons.org/licenses/by-nc/2.0), which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.
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Argentini, S., Mastrantonio, G., Petenko, I. et al. Use of a High-Resolution Sodar to Study Surface-layer Turbulence at Night. Boundary-Layer Meteorol 143, 177–188 (2012). https://doi.org/10.1007/s10546-011-9638-9
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DOI: https://doi.org/10.1007/s10546-011-9638-9