【Grant-in-Aid for (Scientific Research(S)】
公表用資料（英文）Title of Project ： Scientific and Integrated Research by In-situ
Campaign
Observations
SynchronizingVideo-sonde and the Latest Polarimetric Radar,
Heading for Reduction of Water Related
DisasterEiichi Nakakita(Kyoto University, Disaster Prevention Research Institute,Professor)
Research Area：Civil Engineering, Hydraulic Engineering, Hydrometeorology
Keyword：Radar Hydrology, Polarimetric Radar, Video Sonde, Rainfall Estimation, Prediction【Purpose and Background of the Research】
Recently, disaster due to localized heavy rainfall
is noticeable under climate change andurbanization. Although prediction accuracy ofheavy rainfall in large spatial scale is getting
higher and higher, it is still difficult for localized
heavy rainfall in smaller spatial scale to be evenreproduced. Moreover, earlier detection andprediction of localized and suddenly generated
heavy rainfall (so called guerrilla heavy rainfall)
are very important, even if the time lag is five toten minutes. Also, prediction and early warningof flash flood are expected. Under thesecircumstances, this scientific integrated researchaims to execute in-situ campaign observations ofprecipitation using a video-sonde synchronizedwith the latest polarimetric Doppler radar whichis expected to be effective in the rainfall
estimation and prediction. Also, this researchaims to develop methodologies for reducing
water related disaster.
【Research Methods】
The Video-sonde is an expensive instrument
which can take images of hydrometeors. In theautumn of 2010, preliminary campaign
observations will be carried out in Okinawa andShiga prefectures in order to develop a morecompact and sophisticated general type of“video-sonde observation system”. By this newlydeveloped system, continuous video-sonde
observations during various life stages of a
precipitation system will be realized. Forsynchronization, COBRA by NICT in Okinawa
and operational radars by MLIT in Shiga will be
used as the polarimetric Doppler radars.
From 2011 to 2013, the timing of the campaign
observations will be shifted to the Baiu-season.
The MU radar and a cloud radar by RISH, Kyoto
University will also be used for synchronizationin Shiga prefecture. Based on these basic in-situ
observations and obtained products, thisresearch proceeds as follows: 1) Improving
meso-scale atmospheric model by sophisticating
model of cloud micro physics, 2) Developing

assimilation methodology by establishing apolarimetric radar distinction algorithm of typesof co-existing hydrometeoros, 3) Completing
rainfall estimation procedure for operational use,4) Developing earlier detection and prediction
methodologies of guerrilla heavy rainfall, andimproving warning system of flash flood.

Figure 1

Schematic of campaign observation.

【Expected Research Achievements andScientific Significance】
1) The first synchronized observation in theworld. 2) Sophistications of the models of cloudphysics, atmospheric, and rainfall prediction. 3)
Reducing water related disaster such as flashflood.
【Publications Relevant to the Project】
Nakakita, et, al., Develpment of hydrometeor
classification system using polarimetric radarmeasurements synchronized with video-sonde
observation, Annual Journal of HydraulicEngineering, JSCE Vol.53, pp.361-366, 2009.
【Term of Project】 FY2010-2014【Budget Allocation】169,700 Thousand Yen【Homepage Address and Other Contact
Information】
http://hmd.dpri.kyoto-u.ac.jp/nakakita/nakakita_Eng.htm