Status of AMDAR Implementation in Japan

, Forecast Department, Japan Meteorological Agency

Prepared for APSDEU-6Seoul, Korea, 1 June 2005

History of AMDAR in JMA

• 1992 ～ : ASDAR collection via GMS and dissemination via GTS.

• mid 1990’s :Started contact with airlines, and many impact studies performed with off-line ACARS data.

• 2002 : Agreement with JAL for experimental on-line use of ACARS.

• 2003 : Agreement with ANA.• Aug 2004 : Started dissemination via GTS in FM42 form.• Mar 2006 : Planned to disseminate in BUFR form.

Available Data

• Coverage: Within the reach of VHF data link mainly in Japan.

• Data collection strategy: - For flight operation of each airline.

- Ascent, descent data are collected by one airline.

- QNH correction <= 14,000ftDES JP9Z4UU5 2620N 12802E 050239 F/// PS090 235/013 TB/ S031333 F100 VG///=

System OverviewData link provider company

Airline company

J MA

GTS

Numerical Analysis and Prediction System

ACARS Met Data receiverACARS Met data processing server

Met data extractionPseud ID conversionCommunication to J MA

Data for flight operation(including Met)

VHF Remote Ground Stations

Data link Computer

Encoding into FM42

Current AMDAR Encoding

ACARS Met. Data Receiver

MSS

MSS

GTS

GTS

ACARS to AMDAR

Conversion

Elimination Filter

Elimination ListElimination List

ACARSData LinkProvider

ACARSData LinkProvider

JMA

NAPS

NAPS

BUFR Encoding (Plan )

GTS

GTS

JMA

QNH

ACARS Met. Data Processor

MSS

ACARSData LinkProvider

ACARSData LinkProvider

Civil AviationBureau

Civil AviationBureau

Height Correction(Height to Pressure Level)

Height Correction(Height to Pressure Level)

BUFR EncoderElimination Filter

BUFR EncoderElimination Filter

METARMETAR

Elimination ListElimination List

DecoderDecoder

NAPS

NAPS

Impact to NWP

Greatest impact to the JMA Mesoscale model (MSM):

-( J-AMDAR coverage / Model domain ) is large.- Hourly data can be fully ingested to 4D-variational analysis.

Data coverage for MSM

- Radar/AMeDAS rain rate is also assimilated into MSM

Diurnal change of data coverage for MSM

DAYDAY

NIGHTNIGHT

00UTC 06UTC

12UTC18UTC

Daily error sequence on upper air wind(FL210 – FL450)

Mesoscale model (00UTC initial), vs ACARS

Start using ACARS

Lines indicate errors averaged over 25days before and after Aug 26.

Dots indicate daily errors

Month/day in 2002

Statistical verification on upper wind forecast

Comparison between Sep-Oct (with ACARS) and Apr-May (w/o ACARS) Mesoscale Model 250hPa wind forecast error vs radiosonde

Error reduction was small for 18UTC initial （ ACARS not available ）

0.0

0.2

0.4

0.6

0.8

6 12 18

Forecast hours

Red

uction

of

erro

s (m

/s)

Vaild at 00UTCVaild at 12UTC

indicatesforecast from 18UTC (03 Local time) initial

With ACARS

w/o ACARS

Oct 21, 2002 00UTC initial T=3

MOD CAT

MOD CAT

図３

New product: hourly wind analysis

3D-OI based on Mesoscale modelwith ACARS, Wind profiler, Doppler Radar.

Data monitoring of AMDAR for GSM

13 APR 2005 - 24 MAY 2005

DecodedUsed Rejected

DecodedUsedRejected

CYCLE ANALYSIS

EARLY ANALYSIS

- Used data are about 20% of decoded data due to thinning- Very few data rejected in the assimilation system imply the data quality is excellent

AMDAR as verification data for GSM

MEAN: 0.5K, RMSE: 1.6K for APR 2004MEAN: 0.2K, RMSE: 1.5K for APR 2005

300hPa-150hPa, Cycle Analysis

0

0.02

0.04

0.06

0.08

-10 -5 0 5 10

Temperature difference (K) between AMDAR obs. & firstguess of GSM

Freq

uenc

y APR 2005APR 2004

Better consistency between AMDAR observation and first guess implies improvement of model performance.

Thank you!