Editorial Type:
Article
Article Type:
Research Article

Low-Level Easterly Winds Blowing through the Tsugaru Strait, Japan. Part I: Case Study and Statistical Characteristics Based on Observations

Teruhisa Shimada Ocean Environment Group, Center for Atmospheric and Oceanic Studies, Graduate School of Science, Tohoku University, Sendai, Japan

Search for other papers by Teruhisa Shimada in
Current site
Google Scholar
PubMed Close
,
Masahiro Sawada Atmospheric Science Laboratory, Graduate School of Science, Tohoku University, Sendai, Japan

Search for other papers by Masahiro Sawada in
Current site
Google Scholar
PubMed Close
,
Weiming Sha Atmospheric Science Laboratory, Graduate School of Science, Tohoku University, Sendai, Japan

Search for other papers by Weiming Sha in
Current site
Google Scholar
PubMed Close
, and
Hiroshi Kawamura Ocean Environment Group, Center for Atmospheric and Oceanic Studies, Graduate School of Science, Tohoku University, Sendai, Japan

Search for other papers by Hiroshi Kawamura in
Current site
Google Scholar
PubMed Close
Print Publication:
01 Oct 2010
DOI:
https://doi.org/10.1175/2010MWR3354.1
Page(s):
3806–3821
Restricted access

Abstract

This study has investigated structures and diurnal variations of the easterly surface winds blowing throughout the east–west passage comprising the Tsugaru Strait, Mutsu Bay, and circumjacent terrestrial gaps in northern Japan during the summer months. Based on observational and reanalysis data, a representative case study in June 2003 and supplemental statistical analyses are presented. The cool easterly winds accompanied by clouds and fog are blocked by the central mountain range. This condition increases an along-strait sea level pressure (SLP) gradient, which induces strong winds in the west of the strait. The along-strait SLP gradient is enhanced by the developed Okhotsk high and by low pressure systems passing along the southern coast of Japan or over the Japan Sea. Stronger (weaker) and easterly (east-northeasterly) winds are observed during the nighttime (daytime), corresponding to the cool air intrusion from the east (retreat from west). Differences in SLP observed at meteorological observation stations on the east and west can be a good indicator of wind speed in the west of the strait. Meanwhile, the winds over the land also show diurnal variations specific to the times of the prevailing cool easterly winds. The easterly winds over the land are stronger and more divergent across the strait during the daytime than nighttime. This indicates the possibility that the diurnal wind variations are thermally induced. Reduction of diurnal air temperature changes in the east increases east–west thermal contrast. Additionally, the cool air over the strait and the bay can enhance land–sea thermal contrast across the coast.

Corresponding author address: Teruhisa Shimada, Ocean Environment Group, Center for Atmospheric and Oceanic Studies, Graduate School of Science, Tohoku University, Aramaki Aza Aoba 6-3, Aoba-ku, Sendai, Miyagi 980-8578, Japan. Email: shimada@ocean.caos.tohoku.ac.jp

Abstract

This study has investigated structures and diurnal variations of the easterly surface winds blowing throughout the east–west passage comprising the Tsugaru Strait, Mutsu Bay, and circumjacent terrestrial gaps in northern Japan during the summer months. Based on observational and reanalysis data, a representative case study in June 2003 and supplemental statistical analyses are presented. The cool easterly winds accompanied by clouds and fog are blocked by the central mountain range. This condition increases an along-strait sea level pressure (SLP) gradient, which induces strong winds in the west of the strait. The along-strait SLP gradient is enhanced by the developed Okhotsk high and by low pressure systems passing along the southern coast of Japan or over the Japan Sea. Stronger (weaker) and easterly (east-northeasterly) winds are observed during the nighttime (daytime), corresponding to the cool air intrusion from the east (retreat from west). Differences in SLP observed at meteorological observation stations on the east and west can be a good indicator of wind speed in the west of the strait. Meanwhile, the winds over the land also show diurnal variations specific to the times of the prevailing cool easterly winds. The easterly winds over the land are stronger and more divergent across the strait during the daytime than nighttime. This indicates the possibility that the diurnal wind variations are thermally induced. Reduction of diurnal air temperature changes in the east increases east–west thermal contrast. Additionally, the cool air over the strait and the bay can enhance land–sea thermal contrast across the coast.

Corresponding author address: Teruhisa Shimada, Ocean Environment Group, Center for Atmospheric and Oceanic Studies, Graduate School of Science, Tohoku University, Aramaki Aza Aoba 6-3, Aoba-ku, Sendai, Miyagi 980-8578, Japan. Email: shimada@ocean.caos.tohoku.ac.jp

Save
Cover Monthly Weather Review
Monthly Weather Review

  • Bond, N. A., and P. J. Stabeno, 1998: Analysis of surface winds in Shelikof Strait, Alaska, using moored buoy observations. Wea. Forecasting, 13 , 547–559.

    • Search Google Scholar
    • Export Citation

  • Chelton, D. B., M. H. Freilich, and S. K. Esbensen, 2000: Satellite observation of the wind jets off the Pacific coast of Central America. Part II: Regional relationships and dynamical consideration. Mon. Wea. Rev., 128 , 2019–2043.

    • Search Google Scholar
    • Export Citation

  • Colle, B. A., and C. F. Mass, 2000: High-resolution observations and numerical simulations of easterly gap flow through the Strait of Juan de Fuca on 9–10 December 1995. Mon. Wea. Rev., 128 , 2398–2422.

    • Search Google Scholar
    • Export Citation

  • Haack, T., S. D. Burk, C. Dorman, and D. Rogers, 2001: Supercritical flow interaction within the Cape Blanco–Cape Mendocino orographic complex. Mon. Wea. Rev., 129 , 688–708.

    • Search Google Scholar
    • Export Citation

  • Hersbach, H., A. Stoffelen, and S. de Haan, 2007: An improved C-band scatterometer ocean geophysical model function: CMOD5. J. Geophys. Res., 112 , C03006. doi:10.1029/2006JC003743.

    • Search Google Scholar
    • Export Citation

  • Horstmann, J., W. Koch, S. Lehner, and R. Tonboe, 2000: Wind retieval over the ocean using synthetic aperture radar with C-band HH polarization. IEEE Trans. Geosci. Remote Sens., 38 (5) 2122–2131.

    • Search Google Scholar
    • Export Citation

  • Kawai, Y., K. Otsuka, and H. Kawamura, 2006: Study on diurnal sea surface warming and a local atmospheric circulation over Mutsu Bay. J. Meteor. Soc. Japan, 84 , 725–744.

    • Search Google Scholar
    • Export Citation

  • Kanno, H., 2004: Five-year cycle of north-south pressure difference as an index of summer weather in northern Japan from 1982 onwards. J. Meteor. Soc. Japan, 82 , 711–724.

    • Search Google Scholar
    • Export Citation

  • Kodama, Y-M., Y. Toiya, and S. Asano, 2009: Air mass transformation along trajectories of airflow and its relation to vertical structures of the maritime atmosphere and clouds in Yamase events. J. Meteor. Soc. Japan, 87 , 665–685.

    • Search Google Scholar
    • Export Citation

  • Kojima, M., S. Asano, and H. Iwabuchi, 2006: Time-variations of optical and microphysical properties of Yamase clouds estimated from shipboard experiments and satellite remote sensing in June 2003. SOLA, 2 , 45–48.

    • Search Google Scholar
    • Export Citation

  • Mass, C. F., S. Businger, M. D. Albright, and Z. A. Tucker, 1995: A windstorm in the lee of a gap in a coastal mountain barrier. Mon. Wea. Rev., 123 , 315–331.

    • Search Google Scholar
    • Export Citation

  • Monaldo, F. M., D. R. Thompson, W. G. Pichel, and P. Clemente-Colòn, 2004: A systematic comparison of QuikSCAT and SAR ocean surface wind speeds. IEEE Trans. Geosci. Remote Sens., 42 (2) 283–291.

    • Search Google Scholar
    • Export Citation

  • Ninomiya, K., and H. Mizuno, 1985a: Anomalously cold spell in summer over northeastern Japan caused by northeasterly wind from polar maritime air-mass. Part 1. EOF analysis of temperature variation in relation to the large-scale situation causing the cold summer. J. Meteor. Soc. Japan, 63 , 845–857.

    • Search Google Scholar
    • Export Citation

  • Ninomiya, K., and H. Mizuno, 1985b: Anomalously cold spell in summer over northeastern Japan caused by northeasterly wind from polar maritime air-mass. Part 2. Structure of the north-easterly flow from polar maritime airmass. J. Meteor. Soc. Japan, 63 , 859–871.

    • Search Google Scholar
    • Export Citation

  • Onogi, K., and Coauthors, 2007: The JRA-25 Reanalysis. J. Meteor. Soc. Japan, 85 , 369–432.

  • Overland, J. E., 1984: Scale analysis of marine winds in straits and along mountainous coasts. Mon. Wea. Rev., 112 , 2530–2534.

  • Rikiishi, K., and Y. Sasaki, 1990: Yamase and the land and sea breeze (in Japanese). Kaiyo Mon., 22 , 401–407.

  • Schoenberger, L. M., 1984: Doppler radar observation of a land breeze cold front. Mon. Wea. Rev., 112 , 2455–2464.

  • Sharp, J., and C. Mass, 2004: Columbia Gorge gap winds: Their climatological influence and synoptic evolution. Wea. Forecasting, 19 , 970–992.

    • Search Google Scholar
    • Export Citation

  • Shimada, T., and H. Kawamura, 2007: Case study of wind jet transition and localized responses of wind wave along the Pacific coast of northern Japan by synergetic use of satellite and in situ observations. J. Oceanogr., 63 , 953–966.

    • Search Google Scholar
    • Export Citation

  • Shimada, T., and H. Kawamura, 2009: Comparison of wind and wave fields between high-resolution simulations and operational forecast products: A case of wave development under easterly wind jets in the west of the Tsugaru Strait. J. Integr. Field Sci., 6 , 15–22.

    • Search Google Scholar
    • Export Citation

  • Takai, H., H. Kawamura, and O. Isoguchi, 2006: Characteristics of the Yamase Winds over oceans around Japan observed by the scatterometer-derived ocean surface vector winds. J. Meteor. Soc. Japan, 84 , 365–373.

    • Search Google Scholar
    • Export Citation

  • Tang, W., W. T. Liu, and B. W. Stiles, 2004: Evaluation of high-resolution ocean surface vector winds measured by QuikSCAT scatterometer in coastal regions. IEEE Trans. Geosci. Remote Sens., 42 , 1762–1769.

    • Search Google Scholar
    • Export Citation

  • Yamaguchi, S., and H. Kawamura, 2005: Influence of orographically steered winds on Mutsu Bay surface currents. J. Geophys. Res., 110 , C09010. doi:10.1029/2004JC002462.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 283 112 10
PDF Downloads 160 49 4