Presentation on theme: "Ni Yunqi Chinese Academy of Meteorological Sciences State Key Laboratory of Severe Weather State Key Basic Research Development Program China Heavy Rainfall."— Presentation transcript:
Ni Yunqi Chinese Academy of Meteorological Sciences State Key Laboratory of Severe Weather State Key Basic Research Development Program China Heavy Rainfall Experiment China Heavy Rainfall Experiment (CHeREX) in 2007/2008
1. Purpose and Significance
1 ） Heavy rainfall is one of main disasters in south China. But heavy rainfall caused by strong convective systems with several tens km- 200 km space scale (meso- β scale).
2002/06/ /3h There are a series of Meso-scale systems within Meiyu front, which caused heavy rainfall and it could induce flooding.
The landed tropical cyclone Billis caused heavy rainfall and flooding in southern China, which caused big economic loses and over six hundreds peoples died. In fact, the heavy rainfall was caused by activities of meso-scale convective systems in the cyclone.
2 ） It is also difficult to predict heavy rainfall by using the numerical model.
The capability of forecasting heavy rainfall by using numerical model is still lower. Ts score for AREM model in 2003 summer AREM_3Dvar meso-scale model HLAFS0.25 operational regional model regional model T213 Global model
1 ） three dimensional structure, formation mechanism and physical processes of the convective systems with meso β scale still is not very clear. 2 ） We can’t provide a initial condition involving a lot of meso-scale information for numerical model.
If we want to really understand meso-scale convective systems and improve capability of forecasting heavy rainfall we have to get the data as follows: 1) the meteorological data described three dimensional structure of meso-scale convective system and its variation; 2) parameters of micro-physical processes of inside of could. Therefore, organizing a field experiment to get the above data is very important for studying and forecasting heavy rainfall events.
2. Objectives, regions and period of CHeREX
1) Objectives (1) Establish a high resolution meso-scale observation network with time and space,which can obtain three dimensional structure data of meso-scale system; (2) developing a meso-scale reanalysis system and forming a high resolution grid meteorological fields with time; (3) improve heavy rainfall prediction by using the above data with real time.
2) Experimental region The experimental region includes all the Guandong province with parts of GuangXi province 、 FuJian province 、 HuNan province 、 JiangXi province 、 HongKong 、 Marco.
3) Experimental period It is May- July in 2007 and maybe extended to 2008.
The organizer of this heavy rainfall experiment is: (1) The project “Research on Detecting and Forecasting Theories and Methods for Heavy Rainfall Causing Flooding in Southern China” from State key Basic Research Developing Program in China; (2) State Key Laboratory of Severe Weather.
3. Design of observation network with meso-scale
Distribution of annual mean heavy rainfall days in Guandong
Guandong Province meso-βscale observation region EquipmentsNumber Doppler radar operational6 Movable4 Sounding station Operational6 GPS sounding/boundary layer 15 Wind profile3 Surface stationsoperational30 Auto-stations 300 GPS/moisture
We can retrieve the data from dual- Doppler radars to get three dimensional wind field with high resolution. Therefore, we construct three dual Doppler radar network in the central region of the experimental area.
配对雷达的距离适中： 60 － 80KM 立体扫描时间短，层数要尽量多 Retrieval area of dual-Doppler radars 两个雷达径向速度 的夹角在（ 30 － ） 之间 广州 龙门
广卅 龙门 CAPPI 1km 2km 3km PPI 1层1层 2层2层 3层3层 4层4层 Retrieval layers in vertical for dual-Doppler radars
业务雷达 广州 23º 00′113º 21′ 深圳 22º 33′114º 06′ 香港 22º 15′114º 08′ 澳门 22º 10′113º 33′ 车载雷达 龙门 23º 44′114º 14′ 惠阳 23º 05′114º 25′ 广州 香港 澳门 龙门 深圳 惠阳 Dual-Doppler Radar Network in Southern China meso—β Obs. Region in Southern China meso—β Obs. Region
(3) Movable Observation Systems
Movable Observing System Satellite Radar on plane Drop sounding Processing & Prediction system Movable radar Operation radar
运－ 8 飞机 (10499) 图 154 (11900m )
美国 35G 测云雾雷达 /20Km
3830 、 3830J Movable C-band Doppler Radar
（ 4 ） Using satellite remote sensing retrieved data make up lack of data, especially in the ocean areas.
Analysis using remote sensing retrieval data for three dimensional temperature & moisture structure of meso-scale system
4. Database and data share of CHeREX
5. Headquarters of CHeREX
CHeREX Leaders group CHeREX Headquarters CHeREX Office Working group Of meso –scale Obs. Working group Of Data processing Working group of Analysis of satellite remote sensing Working group Of database Working group of Quick look & meso-scale analysis Working group of reanalysis & prediction Headquarters Organization Flow Chart
6. International Collaboration
1)Japan: Institute of Observation Research for Global Change/JAMSTEC, Dr. Yoshizaki Masanori group. 2)Korea: School of Earth and Environmental Sciences of Seoul National University, Prof. Dong-Kyou Lee. 3) United States: (1) University of Marland, Prof.Da-Lin Zhang; (2) Texas A & M University, Prof.Fuqin Zhang; (3) University of Miami, Dr.Shuyi Chen.
7. Several basic problems need to be solved
1)Decided where are the sensitive areas for prediction of meso-scale heavy rainfall vir experiments & research of meso –scale observation; 2)Implement target observation. That is Sensitive areas + predicted area = the target observation areas
3) Establish the interact system between observation system and prediction system. In this case we can use the real time data to improve prediction accuracy of heavy rainfall. 4) Developing a reanalysis system with high-resolution. As a result, a reanalysis meteorological field with high resolution is formed.
1)In order to obtain high-resolution with time & space three dimensional data we will implement the field experiment of heavy rainfall in southern China in May-July 2007/ )Characteristics of CHeREX are (1) establish dual-Doppler observation network with four operational Doppler radars and two movable Doppler radars; (2) implement dropsonde detecting three dimensional structure data; (3) Using dual polarized Doppler radar to detect the parameters inside of cloud; (4) Increasing sounding density in space by using GPS/boundary layer sounding.
3)It is necessary to us satellite remote sensing to increase meso-scale observed information including COSMIC; 4)In this experiment we have to develop meso- scale reanalysis system which assimulaes and integrates different kinds of observed data. As a result, The meso-scale reanalysis field is formed; 5)We must develop interact system between observation system and prediction system. 6)The data from CHeREX should be shared under certain condition.