Diurnal Variations in Summertime Surface Wind upon Japanese Plains: Hodograph Rotation and Its Dynamics

Sakazaki, Takatoshi; Fujiwara, Masatomo

doi:10.2151/jmsj.86.787

Cited by 12 publications

(14 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This veering indicates a competition between two onshore flows, a SE flow below 200 m and a deeper SSW flow. However, the Coriolis force influences the veering of the wind vectors during the daytime in the Northern Hemisphere (e.g., Haurwitz, 1947;Sakazaki and Fujiwara, 2008). Here, the vertical structure confirms the dual SB formations already observed in the near-surface measurements.…”

Section: Sodar Datasupporting

confidence: 82%

Characteristics of shallow thermally driven flow in the complex topography of the south-eastern Adriatic

Prtenjak

Tomažić²,

Kavčič

et al. 2010

Ann. Geophys.

View full text Add to dashboard Cite

Abstract. Characteristics of thermally induced flow, namely the sea breeze, are investigated along the south-eastern Adriatic. The chosen period 24-25 April 2006 favoured sea breeze development and simultaneously allowed a comparison of the large-scale wind influence (north-westerly wind versus south-easterly wind) and the complex terrain on the local circulations. Particular attention is paid to the smallscale formation of the wind field, convergence zones (CZs), channelling flows and small scale eddies, especially in the vicinity of two airports in the central part of south-eastern Adriatic. The results are based on wind measurements (from meteorological surface stations, radiosoundings, satellite data and sodar data) and further supplemented by model data at fine grid spacing.This study shows the formation of numerous irregular daytime and nighttime CZs, which occurred along the coastline in the lee of mountains and over the larger, elongated islands. The results show that the above mentioned airports are surrounded by daytime CZ formations within the lowermost 1000 m and associated updrafts of 1 m s −1 , especially if CZs are maintained by the north-westerly largescale winds. Whereas the daytime CZ was generated due to merged sea breezes, the weaker and shallower nighttime CZs were formed by wind convergence of the seaward breezes, and significantly modified by the large-scale flow of the topography (e.g., accelerated flow in the sea channels and substantial swirled flows around the islands).The passes between the coastal mountain peaks changed the inflow penetration, provoking the increase in wind speed of the channelled flow. The strongest sea breeze channellingCorrespondence to: M. T. Prtenjak (telisman@gfz.hr) was observed above the valley of the Neretva River, where the onshore flow reached 40 km inland with a strength of 8 m s −1 , and the highly asymmetric offshore part was confined within the sea channel.

show abstract

Section: Sodar Datasupporting

confidence: 82%

Characteristics of shallow thermally driven flow in the complex topography of the south-eastern Adriatic

Prtenjak

Tomažić²,

Kavčič

et al. 2010

Ann. Geophys.

View full text Add to dashboard Cite

show abstract

“…This relationship was confirmed by Bian (1995, 1996), based on data from the wind profiler network in the USA. Sakazaki and Fujiwara (2008) confirmed a robust semidiurnal component in surface wind that is caused by the non-sinusoidal local pressure gradient force associated with local wind systems. Note that the height range up to which local wind systems control the semidiurnal wind component remains poorly understood.…”

Section: Introductionmentioning

confidence: 58%

“…The hodograph represents diurnal variations in the wind vector at a given point. Details of the method employed in analyzing hodographs can be found in Sakazaki and Fujiwara (2008). The harmonic dial vector represents the amplitude and phase of any harmonic component based on its length and direction, respectively.…”

Section: Spatial Inhomogeneitymentioning

confidence: 99%

“…Being relatively easy to measure, surface wind patterns have been reported in many previous studies conducted throughout the world (e.g., see Miller et al 2003 for a review of studies on land-sea breezes). Sakazaki and Fujiwara (2008) recently investigated the surface wind upon Japanese plains and found that diurnal variations upon plains of 50-100 km in scale are explained mainly by the lagged combination of land-sea and mountain-valley breezes. Di¤erent types of ''local-scale'' wind systems are sometimes coupled to generate ''regional-scale'' (@100 km) wind systems (e.g., Kurita et al 1990).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Diurnal Variations in Lower-Tropospheric Wind over Japan Part I: Observational Results using the Wind Profiler Network and Data Acquisition System (WINDAS)

Sakazaki

Fujiwara

2010

Journal of the Meteorological Society of Japan

Self Cite

View full text Add to dashboard Cite

This study investigates diurnal variations in lower-tropospheric wind over Japan during [2002][2003][2004][2005][2006][2007][2008] using data from 31 stations of the Wind profiler Network and Data Acquisition System (WINDAS) and the Automated Meteorological Data Acquisition System (AMeDAS). The diurnal and semidiurnal components are extracted and analyzed to identify the dominant processes for each height range and for each season. Near the surface, the diurnal component is controlled by local wind systems (e.g., land-sea breezes) throughout the year. At 1-3 km, the diurnal component is primarily controlled by the return currents of local wind systems, with additional influence by other disturbances; the superposition of these two wind systems generates amplitude maxima in spring (@0.5 m s À1 ) and autumn (@0.6 m s À1 ). At 3-5 km, the diurnal wind in DJF-MAM is controlled by mediumscale eastward traveling waves, which generate the amplitude maximum (@0.8 m s À1 ) in winter-spring. In JJA-SON, the diurnal component is controlled by a large-scale wind system with an amplitude of @ 0.3 m s À1 , probably related to the diurnal tide. At stations located on small islands located south of the Japanese mainland, the diurnal wind within the lower troposphere has di¤erent characteristics from those described above throughout the year. Throughout Japan, the semidiurnal wind component is controlled by the semidiurnal migrating tide above @ 1 km, and is influenced by local wind systems below @1 km. The amplitude of the semidiurnal tide below 5 km is largest in DJF (@0.4 m s À1 ) and smallest in JJA (@0.2 m s À1 ).

show abstract

“…SMS provides precipitation intensity and air temperature data on a 10-min time scale from 1992 to 2011 (Kikuchi et al, 2001;Sakazaki and Fujiwara 2008;Farukh and Yamada 2014). We analyzed the SMS dataset to investigate the relationship between P 99 (T ) and the corresponding surface air temperatures.…”

Section: Datamentioning

confidence: 99%

Extreme precipitation intensity in future climates associated with the Clausius-Clapeyron-like relationship

Yamada

Farukh

Fukushima

et al. 2014

Hydrological Research Letters

View full text Add to dashboard Cite

Abstract:This paper introduces a method named "hybrid-downscaling" to estimate the future extreme hourly precipitation intensity based on observational evidence of the 99th percentile precipitation intensity against air temperature in Sapporo and Tokyo, Japan. The future projected air temperature under the Special Report on Emissions Scenarios (SRES) A1B was used after dynamical downscaling using 3 different regional atmospheric models (RAMs) with lateral boundary conditions from 3 different general circulation models (GCMs). We analyzed the 99th percentile of hourly precipitation intensity against daily mean air temperature in Sapporo and Tokyo. The 99th percentile precipitation intensity tended to have an approximate equation in which the rate of increment was similar to the Clausius-Clapeyron rate of change in the saturated water vapor. This study also showed that the precipitable water vapor and the convective instability followed the Clausius-Clapeyron-like rate of change during the hours with the 99th percentile precipitation intensity.

show abstract

Diurnal Variations in Summertime Surface Wind upon Japanese Plains: Hodograph Rotation and Its Dynamics

Cited by 12 publications

References 30 publications

Characteristics of shallow thermally driven flow in the complex topography of the south-eastern Adriatic

Characteristics of shallow thermally driven flow in the complex topography of the south-eastern Adriatic

Diurnal Variations in Lower-Tropospheric Wind over Japan Part I: Observational Results using the Wind Profiler Network and Data Acquisition System (WINDAS)

Extreme precipitation intensity in future climates associated with the Clausius-Clapeyron-like relationship

Contact Info

Product

Resources

About