1. THE GLOBAL AMDAR SYSTEM
Third WMO Workshop
On the Impact of Various Observing Systems on NWP
Alpbach March 2004
THE GLOBAL AMDAR SYSTEM By
J. Stickland, Technical Coordinator
WMO AMDAR Panel

3. Data Requirements Desirable Horizontal Spatial and Temporal Density:
1 profile on 250 km grid at 3 hourly intervals
BASIC Data

4. Data Requirements (cont.)
Additional Data

5. WHAT DOES AMDAR PROVIDE?
Trigger Level 1
part 1
Ascent
part 2
Ascent
Trigger Level 2
Typically every min
Level flight phase
Descent
part 1
Descent
part 2
Pressure Based Triggering Time Based Triggering
Ascent Part 1: 5 or 10 hPa intervals 3 to 20 second intervals (default 6)
for first 100 hPa for 30 to 200 seconds (default 90)
Ascent Part 2: 25 or 50 hPa intervals 20 to 60 second intervals (default 20)
above first 100 hPa for 490 to 1050 seconds (default 510)
Enroute: to 60 minute intervals (default 7)
Descent Part 1: 25 or 50 hPa intervals 20 to 300 second intervals (default 40)
from TOD to last 100 hPa from top of descent to surface.
Descent Part 2: 5 or 10 hPa intervals
for last 100 hPa

6. Mandatory and Optional Reported Elements
Element Mandatory/Optional Requires Additional Onboard Processing
Aircraft identifier M
Phase of flight M
Latitude M
Longitude M
Day & time of observation M
Pressure altitude M
Static air temperature M
Wind direction M
Wind speed M
Maximum wind M
Roll & pitch angle flag M *
Humidity O *
Turbulence O *
Icing O *

8. 24 Hour Global Coverage

9. 10 Countries Producing AMDAR Observations
Oceania Nth America Europe Africa
Australia US Netherlands South Africa
New Zealand UK Namibia
France
Sweden
Germany
Note: 5 European providers are supported by 18 EUMETNET countries
15 Airlines
Qantas United KLM SAA
Air New Zealand American BA Air Namibia
North West Air France
Delta SAS
Fed Ex Lufthansa
UPS

10. Countries Testing New AMDAR Programs
* Canada (Air Nova, extending to other regionals and Air Canada)
* Hong Kong China (Cathay Pacific)
* China * Repub. of Korea (Korean Air)
* Saudi Arabia (Saudia) * Japan (JAL, ANA, +)
Countries Developing, Planning or Considering New AMDAR Programs
* Southern Africa Region * Egypt * Ireland (Air Lingus)
* Chile (Lan Chile) * India * Portugal (TAP)
* Argentina (Aerolineas) * Russian Federation * Spain (Iberia)
* Brazil * Poland (LOT) * Austria (Lauda)
* United Arab Emirates (Emirates) * Hungary (Malev) * Switzerland
* Oman (Oman Air, Gulf Air) * Ukraine * Iceland (Iceland Air)
* Morocco (RAM) * Finland (Finnair) * Italy

11. Countries Providing Targeted Observations
The use of AMDAR equipped foreign aircraft operating into remote airports to provide observation profiles and over-flight data. Data are provided by the host airline/NMS on the GTS through a fully automated control system.
Operational Scenarios:
Contributing routine observations to data sparse areas;
Supporting upper air programs of other NMSs with routine data;
Supporting additional operational requirements for additional data, eg. special synoptic or research events.
Countries Providing Targeted Observations
Australia, US, Europe (E-AMDAR)

12. Collaborative Targeted Programs
Collaborative programs of targeted observations between NMSs consist of 2 models:
Formal or informal agreements between data provider and recipient NMSs or regions that may include the recipient reimbursing the provider for marginal operational costs.
Examples include:
ASECNA group (E-AMDAR)
Canada (E-AMDAR)
South Africa (E-AMDAR, Australia)
SW Pacific and SE Asia (Australia, US)
Middle East (E-AMDAR)
Hong Kong (Australia, US)

13. Providers contribute data as part of their own programs or through commitment to the WMO WWW Programme.
Examples include:
Africa (E-AMDAR)
Caribbean, Central America & Gulf of Mexico (US, E-AMDAR)
Eastern Europe and Russian Fed. (E-AMDAR)
South America (E-AMDAR, US)
Global (selective: US, Australia, E-AMDAR)

14. Blue - Routine program Red - Targeted Program
E-AMDAR Targeting into Middle East, Eastern Europe & Independent States
Blue - Routine program
Red - Targeted Program

15. Potential Airports Served by E-AMDAR
Data Targeting
Potential Airports Served by E-AMDAR
* Information compiled from data available on E-ADOS. Figures for 3, 6 and 12 hourly airports are for the EUCOS area.
** Figures are for global data – there were 137 airports providing profile data.

16. Network Optimisation:
The automated control of collecting AMDAR data -
through selection by phase of flight
at appropriate temporal and spatial density
to minimise data redundancy
to improve cost effectiveness.
Techniques:
ground based system through uplinking using scheduled flight and/or real time aircraft operations information
onboard software control using flight phase, lat/long boxes, airport lists, time windows;
Applications:
Regional
Global potential

17. E-AMDAR Optimisation
Reduction of 37% in Lufthansa observations following automated optimisation

18. Optimised E-AMDAR Data

19. Optimised E-AMDAR Data
AMDAR NETWORK PERFORMANCE
Month
Average number of airports with
Average number of airports
Covered per
day
Average number of obs per day.
Average number of profiles per day
3 hourly profiles or better
6 hourly profiles
12 hourly profiles
Less frequently than 12 hourly
Oct 2003* 35 27 28 14
104
22,758**
778**
Dec 2002 21 26
102
23,424
636
Jan 2002 25 19 42
111
25,916
785
Jan 2001 16 18 31 58
123
25,446
729
May 2000 8 61
108
21,770
621
Feb 2000 10 50 88
12,657
422
Definitions:
3 hourly profiles – at least one profile each and every 3 hourly time period between 09Zm and 21Z
6 hourly profiles – at least one profile each and every 6 hourly time period between 06Zm and 24Z
12 hourly profiles – at least one profile each and every 12 hourly time period between 00Zm and 24Z
* Information compiled from data available on E-ADOS. Figures for 3, 6 and 12 hourly airports are for the EUCOS area.
** Figures are for global data – there were 137 airports providing profile data.

20. AMDAR Data Monitoring and Control
Capability
Level 1
Level 2
Level 3
Airlines
Remedial
Action
Feedback
National/Regional
AMDAR Centres
Acquisition &
Optimisation
Focal Points TC
WMO
AMDAR Panel
Fault Investigation
Reports
Daily
Monthly
National/Regional
Monitoring Centres
Global Monitoring
Centres

21. Data Fault Reporting and Remedial Action
Monitoring Centre - detects systematic fault;
- advises relevant national or regional Focal Point or, if unsure which region/country is involved, the AMDAR Panel TC
Panel TC (as required) contacts relevant Focal Point;
Focal Point - conducts preliminary investigation;
- determines relevant airline;
- arranges for inhibiting data distribution on GTS;
- requests remedial action by airline who advise expected fix date;
- provides feedback to the initiating monitoring centre and as appropriate, to the Panel TC and other monitoring centres;
- continues monitoring data or requests airline to cease transmissions

22. Airline - takes remedial action;
- advises Focal Point when data are again expected to be acceptable.
Focal Point - continues to monitor data quality until acceptable again;
- releases data on the GTS for operational use;
- advises monitoring centres

23. Data Quality Processing
Level 1 - Onboard Aircraft:
Sensor buddy checks;
Smoothing filter to improve resolution of quantised observations and to reduce impact of outlyers;
Range and rate of change checks;
Level 2 - Data Acquisition System:
Format checks on incoming message;
Range and rate of change checks on all elements;
Checks following encoding in AMDAR FM42 or FM94 BUFR;
Bulletin preparation and transmission on GTS;
Use of manual and automatic data quality flags to inhibit data distribution

24. Level 3 - National, Regional & Global Centres:
As part of the assimilation process, all of the above plus a wide range of additional sophisticated checks.
International Monitoring Standards:
WMO has established a standard set of monitoring and rejection criteria for operational AMDAR data that will be implemented by all monitoring centres

25. KNMI QEV Report - April - June 2003
Frequency distribution of the mean temperature difference (OBS–Background)
KNMI QEV Report - April - June 2003

26. KNMI QEV Report - April - June 2003
Frequency distribution of the mean wind speed difference (OBS–Background)
KNMI QEV Report - April - June 2003

27. KNMI QEV Report - April - June 2003
Frequency distribution of the mean temperature difference (OBS–Background)
KNMI QEV Report - April - June 2003

28. Frequency distribution of the mean of the absolute wind direction difference (|OBS–Background|) KNMI QEV Report - April - June 2003

31. “New” Observations 1. Humidity/Water Vapour
5 candidate sensors are in varying stages of development:
(1) US – WVSSII (Spectralabs and UCAR) uses proven laser diode technology matched with a new air intake device. Purchase and installation costs are estimated to be US$24k. Operational evaluation trials are due to commence in the 2nd quarter of 2004 on 35 UPS B757s. Other countries including Australia and the E-AMDAR group are also planning to assist with certification and evaluation on Airbus aircraft.
(2) US – TAMDAR (ODS now AIRDAT)) system has a multi-sensor package that includes a humidity sensor for use in the lower to mid troposphere. Operational evaluation trials of 60 sensors will commence on Saab 340 aircraft of regional airline Mesaba in the US Great Lakes region beginning in April, 2004.  Additional evaluation trials are being planned in Canada, France and Australia.
(3) UK – Cambridge University has developed 2 sensors. The laser diode version will be evaluated in collaboration with the UK Met Office on the BAe146 research aircraft. Plans for commercial production have been considered.

32. (4) Germany – DWD is planning to adapt the capacitative sensor used by the European MOZAIC program on a small number of Airbus A340s to make it suitable for AMDAR aircraft.
(5) Russian Federation – (Central Aerological Observatory) has developed a rapid response Aircraft Condensation Hygrometer (ACH) – an infrared diode cooled mirror device for tropospheric and stratospheric research programs. Adaptation to commercial aviation is being considered.

33. 2. Turbulence
Operational reporting of turbulence in AMDAR commenced in 1985 on Australian aircraft (Derived Equivalent Vertical Gust Velocity (DEVG)), and subsequently on aircraft from New Zealand, UK, Netherlands and France. Used operationally for analysis verification and in some forecasting offices including the London WAFC.
Deviation from normal acceleration (delta g) is reported by some US aircraft.
AIREPS use ICAO turbulence categories
More recently, the US has developed and is evaluating Eddy Dissipation Rate (EDR). This has been adopted by ICAO for automated met reports.
Verification of critical EDR turbulence criteria is under way.
Operational systems are being developed in the US for the aviation industry based on EDR and investigations have begun to assimilate data for NWP.

34. 3. Icing
Various technologies are being developed and evaluated;
Measure ice/no-ice conditions and in some cases, ice accretion;
Operational evaluation trials have commenced in the US and Canada has prepared plans for system testing;
Aimed initially to improve aviation weather services;
May have potential to provide liquid water content and super-cooled large droplet information in the future.

35. Future Directions
Encourage and assist more countries, particularly those in data sparse areas to implement AMDAR programs of targeted observations and if possible their own operational systems on local aircraft
More lower flying regional aircraft will become operational (15k - 20k ft)
New sensors will become operational over the next few years
Encourage the development of regional programs to minimise duplication of effort and to increase cost effectiveness
Continue development of regional and global data monitoring and control systems
Increase in education and training programs
Continue publicising AMDAR to all countries so that they may be aware of the availability of data and its operational usefulness
Further integration of AMDAR into the GOS
END