Abstract
To investigate tubulence characteristics and organized motion within and above an urban canopy, field observations were conducted in July 1991 and November 1992 in Sapporo, Japan. The measurement heights were 5.4, 10.3, 18, 35 and 45 m above ground; the canopy height was 7 m. The profiles of σu peaked slightly above the canopy, while σv and σw had nearly uniform profiles. Vertical profiles of Reynolds stress -\(\overline {u'w'} \) peaked slightly at 1.5 times the canopy height and decreased slowly with height thereafter. A four-quadrant analysis showed that sweep and ejection motions caused high-velocity fluid from above moves downward toward the surface and low-velocity fluid from below moves upward. An ensemble-averaging technique was used to isolate typical features of the flow and temperature fields. A time-height cross-section of velocity vectors and temperature contours showed details of the flow structures associated with temperature ramps. It has been noted that the organized motions play important roles in the transport of heat near the urban canopy, where the sweep motion causes negative temperature fluctuations and the ejection motion causes positive temperature fluctuations.
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Antonia, R. A., Chambers, A. J., Friehe, C. A., and Van Atta, C. W.: 1979, ‘Temperature Ramps in the Atmospheric Surface Layer’,J. Atmos. Sci. 36, 99–108.
Bergström, H., and Högström, U.: 1989, ‘Turbulent Exchange above a Pine Forest. II. Organized Structures’,Boundary-Layer Meteorol. 49, 231–263.
Bowne, N. E. and Ball, J. T.: 1970, ‘Observational Comparison of Rural and Urban Boundary Layer Turbulence’,J. Applied Meteorol. 9, 862–873.
Brook, R. R.: 1972, ‘The Measurement of Turbulence in a City Environment’,J. Applied Meteorol. 11, 443–450.
Clarke, J. F., Ching, J. K. S., and Godowich, J. M.: 1982, ‘An Experimental Study of Turbulence in an Urban Environment’, EPA-600/3-82-062, 167 pp.
Counihan, J.: 1971, ‘Wind Tunnel Determination of the Roughness Length as a Function of the Fetch and Density of Three-dimensional Roughness Elements’,Atmos. Environ. 5, 637–642.
Duckworth, F. S. and Sandberg, J. S.: 1954, ‘The Effect of Cities upon Horizontal and Vertical Temperature Gradient’,Bull. Am. Meteorol. Soc. 35, 198–207.
Finnigan, J. J.: 1979, ‘Turbulence in Waving Wheat. II Structure of Momentum Transfer’,Boundary-Layer Meteorol. 16, 213–236.
Gao, W., Shaw, R. H., and Paw, U. K. T.: 1989, ‘Observation of Organized Structure in Turbulent Flow within and above a Forest Canopy’,Boundary-Layer Meteorol. 47, 349–377.
Garratt, J. R.: 1978, ‘Flux Profile Relations above Tall Vegetation’,Ouart. J. Roy. Meteorol. Soc. 104, 199–211.
Garratt, J. R.: 1980, ‘Surface Influence upon Vertical Profiles in the Atmospheric Near-Surface Layer’,Quart. J. Roy. Meteorol. Soc. 106, 803–819.
Graham, I. J.: 1968, ‘An Analysis of Turbulence Statistics at Fort Wayne, Indiana’,J. Applied Meteorol. 7, 90–93.
Grant, A. L. M. and Watkins, R. D.: 1989, ‘Errors in Turbulence Measurements with a Sonic Anemometer’,Boundary-Layer Meteorol. 46, 181–194.
Grass, A. J.: 1971, ‘Structural Features of Turbulent Flow over Smooth and Rough Boundaries’,J. Fluid Mech. 50, 233–255.
Högström, U., Bergström, H., and Alexandersson, H.: 1982, ‘Turbulence Characteristics in a Near Neutrally Stratified Urban Atmosphere’,Boundary-Layer Meteorol. 23, 449–472.
Hanafusa, T., Fujitani, T., Kobori, Y., and Mitsuta, Y.: 1982, ‘A New Type Sonic Anemometer-Thermometer for Field Operation’,Pap. Meteorol. Geophys. 33, 1–19.
Hanafusa, T., Fujitani, T., Kobori, Y., and Yoshida, M.: 1983, ‘Wind Measurement by a Strong Wind-Type of Three Sonic Anemometer-Thermometers’,Annual Meeting of Japan Society of Meteorol. Autumn, P99 (in Japanese).
Jackson, P. S.: 1978, ‘Wind Structure Near a City Center’,Boundary-Layer Meteorol. 15, 323–340.
Kanda, M. and Hino, M.: 1994, ‘Organized Structures Developing Turbulent Flow within and above a Plant Canopy, using a Large Eddy Simulation’,Boundary-Layer Meteorol. 68, 237–257.
Kaimal, J. C. and Gaynor, J. E.: 1983, ‘The Boulder Atmospheric Observatory’,J. Climate Appl. Meteorl. 22, 863–880.
Kline, S. J., Reynolds, W. C., Schraub, F. A., and Rundstadler, P. W.: 1967, ‘The Structure of Turbulent Boundary Layers’,J. Fluid Mech. 30, 741–773.
Lettau, H.: 1969, ‘Note on Aerodynamic Roughness-Parameter Estimation on the Basic of Roughness-Element Description’,J. Applied Meteorol. 8, 828–832.
Lu, S. S. and Willmarth, W. W.: 1973, ‘Measurements of the Structure of the Reynolds Stress in a Turbulent Boundary Layer’,J. Fluid Mech. 60, 481–511.
Meng, Y., Oikawa, S., and Wakamatsu, S.: 1993, ‘Coherent Structure in and above the Urban Canopy’,Proc. 25th Conf. on Turbulence, Japan. Soc. Fluid Mech. 47–50 (in Japanese).
Nakagawa, H. and Nezu, I.: 1977, ‘Prediction of the Contributions to the Reynolds Stress from Bursting Events in Open-channel Flows’,J. Fluid Mech. 80, 99–128.
Ogawa, Y. and Ohara, T.: 1982, ‘Observation of the Turbulent Structure in the Planetary Boundary Layer with a Kytoon-mounted Ultrasonic Anemometer System’,Boundary-Layer Meteorol. 22, 123–131.
Ogawa, Y., Ohara, T., Wakamatsu, S., Diosey, P.G., and Uno, I.,: 1986, ‘Observation of Lake Breeze Penetration and Subsequent Development of the Thermal Internal Boundary Layer for the Nanticoke II Shoreline Diffusion Experiment’,Boundary-Layer Meteorol. 35, 207–230.
Ohara, T., Uno, I., and Wakamatsu, S.: 1989, ‘Observed Structure of a Land Breeze Head in the Tokyo Metropolitan Area’,J. Applied Meteorol. 28, 693–704.
Oikawa, S.: 1993, ‘Vertical Turbulence Structure in and above the Urban Canopy’,J. Japan Society of Air Pollution,28, 348–358 (in Japanese).
Oke, T. R.: 1976, ‘The Distinction between Canopy and Boundary-Layer Urban Heat Island’,Atmosphere 14, 269–277.
Oke, T. R.: 1987, ‘Boundary Layer Climates’, Routledge, 435 pp.
Panofsky, H. A. and Dutton, J. A.: 1984, ‘Atmospheric Turbulence’, J. Wiley, New York, 397 pp.
Raupach, M. R., Thom, A. S., and Edwards, I.: 1980, ‘A Wind-tunnel Study of Turbulent Flow Close to Regularly Arranged Rough Surfaces’,Boundary-Layer Meteorol. 18, 373–397.
Raupach, M. R., Coppin, P. A., and Legg, B. J.: 1986, ‘Experiments on Scalar Dispersion within a Model Plant Canopy. Part I: The Turbulence Structure’,Boundary-Layer Meteorol. 35, 21–52.
Raupach, M. R.: 1989, ‘Stand Overstorey Processes’,Phil. Trans. R. Soc. Lond.,B324, 175–190.
Raupach, M. R., Finnigan, J. J., and Brunet, Y.: 1989, ‘Coherent Eddies in Vegetation Canopies’,Proc. Fourth Australasian Conf. on Heat and Mass Transfer, Christchurch, New Zealand, 75–90.
Reynolds, W. C. and Hussain, A. K. M. F.: 1972, ‘The Mechanics of an Organized Wave in Turbulent Shear Flow. Part 3. Theoretical Models and Comparisons with Experiments’,J. Fluid Mech. 54, 263–288.
Rotach, M. W.: 1991, ‘Turbulence within and above Urban Canopy’, ETH Technical Report 45, Geogra. Inst. E. T.H., Zurich, 245 pp.
Rotach, M. W.: 1993a, ‘Turbulence Close to a Rough Urban Surface. Part I: Reynolds Stress’,Boundary-Layer Meteorol. 65, 1–28.
Rotach, M. W.: 1993b, ‘Turbulence Close to a Rough Urban Surface. Part II: Variances and Gradients’,Boundary-Layer Meteorol. 66, 75–92.
Roth, M.: 1993, ‘Turbulent Transfer Relationships over an Urban Surface. II: Integral Statistics’,Quart. J. Royal Meteorol. Soc. 119, 1105–1120.
Roth, M. and Oke, T. R.: 1993, ‘Turbulent Transfer Relationships over an Urban Surface. I: Spectral Characteristics’,Quart. J. Royal Meteorol. Soc. 119, 1071–1104.
Shiotani, M. and Yamamoto, G.: 1950, ‘Atmospheric Turbulence over the Large City’,Geophys. Mag. 2, 134–147.
Steyn, D. G.: 1982, ‘Turbulence in an Unstable Surface Layer over Suburban Terrain’,Boundary-Layer Meteorol. 22, 183–191.
Tutu, N. K. and Chevray, R.: 1975, ‘Cross-wire Anemometry in High Intensity Turbulence’,J. Fluid Mech. 71, 785–800.
Uno, I., Wakamatsu, S., Ueda, H., and Nakamura, A.: 1988, ‘An Observational Study of the Structure of the Nocturnal Urban Boundary Layer’,Boundary-Layer Meteorol. 45, 59–82.
Wallace, J. M., Eckelmann, H., and Brodkey, R. S.: 1972, ‘The Wall Region in Turbulent Shear Flow’,J. Fluid Mech. 54, 39–48.
Wyngaard, J. C., Coté, O. R., and Izumi, Y.: 1971, ‘Local Free Convection, Similarity and the Budgets of Shear Stress and Heat Flux’,J. Atmos. Sciences 28, 1171–1182.
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Oikawa, S., Meng, Y. Turbulence characteristics and organized motion in a suburban roughness sublayer. Boundary-Layer Meteorol 74, 289–312 (1995). https://doi.org/10.1007/BF00712122
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DOI: https://doi.org/10.1007/BF00712122