Upper Air Observations

Transcription

1 Upper Air Observations by Japan Meteorological lagency Kenji Akaeda Japan Meteorological Agency JMA s mascot HARERUN

2 Weather Observations by Japan Meteorological Agency Surface Observation Rd Radar Observation Satellite Observation AWS Network AMeDAS Wind Profiler Observation Soundings Observations Department Japan Meteorological Agency

3 Observations Observations to clarify various processes over a Height (km) Satellite observation observat ion wide range of space and time scales. Rada r obser vation Wind profiler Upper air Radiosonde Surface observation Remote Sensing AMeDAS Manned Observatories Horizontal resolution (km) Direct Measurement

4 World Upper Air Network (Radiosonde) :Sounding site(850) GUAN site(166) WMO Raidosonde catalog(jan.2007)

5 JMA Upper-air Observation Network 31 Wind Profilers Wind Profiler Control Center 16 Radiosonde stations Rumoi Muroran Obihiro Sakata Miyako Hamada Takada Fukui Takamatu Kumagaya Tottori Mito Oita Control Center Miham (JMA Headquarters) Izuhara a Katuura Hirado Kawaguchiko Kumamoto Hachijojima Ichiki Shizuoka Kouchi Nagoya Yakushima Shimizu Owase Nobeoka JMA upper-air observation network consists of 31 wind profilers and 16 rawinsonde stations. Upper-wind observations are made at the interval of about 120km. Yonagunijima Naze Minamidaitojim a Wind Profiler in JMA 5

6 ABL (Automatic Balloon Launcher and sounding) Flow of sounding that uses ABL Sounding preparation Ground Check Loading the Radiosonde and Balloon onto a tray The sounding program starts at the specified time Balloon filling Balloon release (Sounding start) Sounding TEMP Message coding/sent Sounding stop Balloon filling Balloon release Sounding preparation Sounding Selecting tray Video (calm) Video (Strong Wind)

7 GPS radiosonde types witch JMA uses T Sensor T Sensor GPS Receiver U Sensor GPS Receiver Antenna U Sensor P Sensor Signal converter Alkaline cell Lithium cell Signal converter Telemetry antenna Telemetry antenna RS 06G GPSsonde (Meisei) mm 160g RS92 SGP SGP GPSsonde (Vaisala) mm 290g

8 Data Flow in Soundings of JMA ABL sites KUSHIRO WAJIMA HACHIJYOUJIMA SHIONOMISAKI To JMA HQ Sounding data Status data To Sites Control command MATSUE NAZE MINAMIDAITO JIMA Ishigakijima For numerical weather prediction models Global Telecommunication System Forecast Made for each models For weather watches WEB Contents Data Strage DATA DATA CONTROL CENTER JMA HQ Manned launched site At CONTROLCENTER Quality control of data Remote-controlling of ABL. MBL sites WAKKNAI SAPPORO AKITA TATENO FUKUOKA KAGOSHIMA CHICHIJIMA MINAMI TORISIMA

9 Antenna System Appearance of Profiler Module Unit Radome Clutter Fence Standard type Radome type (47848 Ichiki, Kagoshima) (47147 Obihiro, Hokkaido) 40 N 30 N 130 E 140 E Wind Profiler in JMA 9

10 W S Wind Measurement using Wind Profiler N Z E θ Doppler velocity by N beam V N Doppler velocity by vertical beam V Z Wind vector (u, v, w) V E VW u 2sin VN VS v 2sin w V Doppler velocity by Doppler velocity by W beam V W E beam V E Z HEIGHT Doppler velocity by S beam V S TIME Beams are emitted Wind direction and wind speed toward five directions. are calculated from five Doppler velocities. Vertical profiles of wind direction and wind speed from near the surface to nearly 5 km levels els are obtained. Wind Profiler in JMA 10

11 Comparison of Rawinsonde and Wind Profiler Measurements Correlation of u and v component measurements for the wind profiler and the rawinsonde, bothlocated at Hachijyojima in u-component: avg m/s std. 2.13m/s v-component: avg m/s std. 2.06m/s Differences between wind profiler and rawinsonde wind component measurements e e s (N=7514). Wind Profiler in JMA 11

12 Example of ground echo rejection Atmospheric echo Upper wind signal strength Received Ground echo Atmospheric echo Doppler velocity Remove ground echo Main lobe Ground echo strength Received signal Doppler velocity Atmospheric echo Side lobes Antenna Clutter fence to prevent ground echo Eliminating spectral component around zerovelocity in the Doppler velocity spectrum. Wind Profiler in JMA 12

13 Example of migrating-birds echo Fukui (47616) 19 NOV 2002 wind Height (km ) Time (JST) Time Wind (JST) Profiler in JMA 13

14 Observation Height Coverage of WINDAS Annual average: 5225m(All), 5181m(No precipitation), 7281m(Precipitation) All weather Non-Precipitation Precipitation Height (m m-agl) Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec Wind Profiler in JMA 14

15 Example of the Hourly Analysis FL170 FL170 06JST 8 OCT 2009 Typhoon 0918 FL010 FL010 Winds and vertical wind shear Stream lines Wind Profiler in JMA 15

16 Application to the Weather Analysis Katuura (47674) 24 NOV 2008 Vertical wind H H L S/N ratio Time (JST) Surface (21LST 24 NOV 2008) Katuura (47674) 24 NOV 2008 Helicity Time (JST) Time (JST) Wind Profiler in JMA 16

17 Comparison of Upper-Air Wind Observations WINDAS Radiosond e Doppler radar Weather condition All-weather All-weather Rainy (snowy) weather Accuracy (m/s) <2 <2 <2 Maximum height (km) 3 9 (depends on weather conditions) (depends on weather conditions) Vertical resolution (km) Horizontal spacing (km) Time between observations (h) Delay in delivery to user (h) or Wind Profiler in JMA 17