Abstract
Seasonal variations of the spectra of wind speed and air temperature in the mesoscale frequency range from 1.3 × 10-4 to 1.5 × 10-3 Hz (10 min to 2 h periods) have been studied through observations over land for one year. Spectrographs [time series of isopleths of spectral densities, f · S(f) vs f] of wind speed and air temperature contain occasional peaks that are attributed to short-lived mesoscale atmospheric activity with narrow frequency bands. Significant spectral peaks of wind speed were found in 19% of the total observations in winter, and in 15–16% in the other seasons; for air temperature, they occured in 12% of observations in autumn, and in 16–19% in the other seasons. The peaks most often occurred in the period range from 30 min to 1 h; most had durations less than 24 h. Mesoscale fluctuations of wind speed and air temperature were highly correlated, and in most cases, phase differences were 90–180 ° with air temperature leading wind speed. Significant spectral peaks of wind speed often occurred during northerly seasonal cold winds in winter, and accompanied tropical and/or mid-latitude cyclones in the other seasons. When the peaks occurred, wind speed was usually relatively high and the atmospheric surface layer was unstable.
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References
Agee, E. M., Chen, T. S. and Dowell, K. E.: 1973, ‘A Review of Mesoscale Cellular Convection’, Bull. Amer. Meteorol. Soc. 54, 1004–1012.
Agee, E. M. and Dowell, K. E.: 1974, ‘Observational Studies of Mesoscale Cellular Convection’, J. Appl. Meteorol. 13, 46–53.
Burt, W. V. and Agee, E. M.: 1977, ‘Bouy and Satellite Observations of Mesoscale Cellular Convection During AMTEX 75’, Boundary-Layer Meteorol. 12, 3–24.
Burt, W. V., Cumming, S., and Paulson, C. A.: 1974, ‘The Mesoscale Wind Field over the Ocean’, J. Geophys. Res. 79, 5625–5632.
Burt, W. V., Crew, H., and Poole, S. L.: 1975, ‘Evidence for Roll Vortices Associated with a Land Breeze’, J. Marine Res. 33, 61–68.
Fielder, F. and Panofsky, H. A.: 1970, ‘Atmospheric Scales and Spectral Gaps’, Bull. Amer. Meteorol. Soc. 51, 1114–1119.
Hess, G. D. and Clarke, R. H.: 1973, ‘Time Spectra and Cross-Spectra of Kinetic Energy in the Planetary Boundary Layer’, Quan. J. Roy. Meteorol. Soc. 99, 130–153.
Ishida, H., Burt, W. V., and Mitsuta, Y.: 1984, ‘The Effects of Mesoscale Convective Cells on the Surface Wind Field over the Ocean’, Boundary-Layer Meteorol. 29, 75–84.
Ishida, H.: 1986, ‘Mesoscale Spatial and Temporal Variability of Meteorological Observations from an Array of Buoys in JASIN-1978’, Boundary-Layer Meteorol. 37, 149–165.
Ishida, H.: 1989, ‘Sprectra of Surface Wind Speed and Air Temperature over the Ocean in the Mesoscale Frequency Range In JASIN-1978’, Boundary-Layer Meteorol. 47, 71–84.
Millard, R. C.: 1971, ‘Wind Measurements from Buoys: a Sampling Scheme’, J. Geophys. Res. 76, 5819–5828.
Mitsuta, Y and Fujitani, T.: 1974, ‘Direct Measurement of Turbulent Fluxes on a Cruising Ship’, Boundary-Layer Meteorol. 6, 203–217.
Mori, Y.: 1980, ‘Spectrum of Long-Period Fluctuations of Surface Wind at Marcus Island’, Mon. Wea. Rev. 108. 1456–1461.
Oort, A. H. and Taylor, A.: 1969, ‘On the Kinetic Energy Spectrum Near Ground’, Mon. Wea. Rev. 97, 623–636.
Overland, J. E. and Wilson, J. G.: 1984, ‘Mesoscale Variability in Marine Winds at Mid-Latitude’, J. Geophys. Res. 89, 10,599–10,614.
Panofsky, H. A.: 1969, ‘Spectra of Atmospheric Variables in the Boundary Layer’, Radio Sci. 4, 1101–1109.
Pierson, W. J.: 1983, ‘The Measurement of the Synoptic Scale Wind over the Ocean’, J. Geophys. Res. 88, 1683–1708.
Smedman-Högström, A. and Högström, U.: 1975, ‘Spectral Gap in Surface-Layer Measurements’, J. Atmos. Sci. 32, 340–350.
Trump, C. L., Neshyba, S. J., and Burt, W. V.: 1982, ‘Effects of Mesoscale Atmospheric Convection Cells on the Waters of the East China Sea’, Boundary-Layer Meteorol. 24, 15–34.
Van der Hoven, I.: 1957, ‘Power Spectrum of Horizontal Wind Speed in the Frequency Range from 0.0007 to 900 Cycles Per Hour’, J. Meteorol. 14, 160–164.
Weinstock, J.: 1980, ‘A Theory of Gaps in the Turbulence Spectra of Stably Stratified Shear Flow’, J. Atmos. Sci. 37, 1542–1549.
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Ishida, H. Seasonal variations of spectra of wind speed and air temperature in the mesoscale frequency range. Boundary-Layer Meteorol 52, 335–348 (1990). https://doi.org/10.1007/BF00119428
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DOI: https://doi.org/10.1007/BF00119428