Numerical study of the high-temperature phenomena in Summer over the inland Kanto Plain

  • Yuya TAKANE, 2009: Numerical study of the high-temperature phenomena in Summer over the inland Kanto Plain .

Abstract

The extremely high-temperature events(EHTE)in Summer has recently become a serious probrem. In this study, the climatological features and the forma-tion mechanisms of the EHTE in Summer over the inland area of the Kanto Plainare investigated using observational data and the Weather Research and Forcast-ing(WRF)model.The 682 events(subject to Statistical analysis)(11-years; 1998-2008)are clas-sified into the following three types: Extremely high-temperature event(EHTE),High-temperarure event(HTE), and Normal event. In order to understand thedifference between EHTE and HTE, pressure patterns and each meteorologicalelements are climatologically analyzed by weather charts and observational data.The main differences between EHTE and HTE are as follows:(1)Probabil-ity of a Kujira-no-o type(a summer-type pressure patten)occurring(EHTE>HTE),(2)NorthWest(NW)-wind for EHTE and SouthWest(SW)-wind forHTE at 700 hPa and 850 hPa,(3)Probability of a NW-wind event occurrenceat the surface(EHTE>HTE),(4)Mean temperature observed at 850 hPa(EHTE>HTE),(5)Mean sunshine duration(EHTE>HTE),(6)Meanstability(EHTE<HTE),(7)Mean daily maximun temperature(Tmax)of theprevious day to the event(EHTE>HTE),(8)Mean increase in temperaturefrom the early morning(EHTE>HTE),(9)Mean daily minimum temperature(EHTE>HTE).(2)and(3)suggests a temperature increase by the foehnphenomenon during EHTE. However, the statistical analysis indicates that thefoehn phenomenon did not have a big impact on Tmax. It seems that(4)-(6)and(7)contribute to(8)and(9), respectively. As mentioned above, thereare differences in the meteorological elements between EHTE and HTE. The re-sults suggest that the EHTE are caused by not only a particular factor but by theinteraction of multiple factors.

The following paper was based on a portion of his Master's thesis was published in International Journal of Climatology.(2014).

Takane, Y., H. Kusaka, and H. Kondo, 2014: Climatological study on mesoscale extreme high temperature events in the inland of the Tokyo Metropolitan Area, Japan, during the past 22 years. International Journal of Climatology, DOI:10.1002/joc.3951. 2014.02.01(Acknowledgment:S8, RECCA)

International Journal of Climatology(Wiley Online Library)

The following paper was based on a portion of his Master's thesis was published in J. Appl Meteor Clim.(2011).
Takane, Y., Kusaka, H., 2011: Formation mechanism of the extreme surface air temperature of 40.9 C observed in the Tokyo metropolitan area: Considerations of dynamic foehn and foehn-like wind. J. Appl. Meteor. Clim., 50(9), 1827-1841. 2011.09.01(Acknowledgment:S5, S8, T2K) .
American Meteorological Society(AMS)

Best Presentation Award(2008).
Takane,Y.,H.Kusaka,M.Hara,S.A.Adachi,and F.Kimura,2008:Formation mechanism of extreme hot conditions
-a case study on 16 August 2007-.3rd Conference on heat island Japan,2008
Certificate of merit