Aircraft-Based Observations Dataset
DescriptionMany commercial aircraft operating in the world today are equipped with sensors that can provide real-time weather observations (primarily winds and temperatures) via radio downlinks.
The MADIS Aircraft-Based dataset provides data obtained from many U.S. airlines reporting through the Aircraft Communications Addressing and Reporting System (ACARS), managed by Aeronautical Radio, Inc. (ARINC). ACARS is a superset of the Meteorological Data Collection and Reporting System (MDCRS) data that's available via NOAAPORT. In addition to the ACARS data, the MADIS dataset also includes Aircraft Meteorological Data Reporting (AMDAR) data from many European and Asian carriers, and Tropospheric Airborne Meteorological Data Reporting (TAMDAR) data.
More than 60 TAMDAR sensors have been deployed on turboprop aircraft operated by Mesaba Airlines (d. b. a. Northwest Airlink). This fleet of aircraft provides high vertical resolution sounding data at regional airports in the Eastern half of the United States. A map of the Mesaba routes can be found here (the TAMDAR routes are shown in green), and generally provides high temporal resolution data at lower altitudes than is the case with currently available automated weather data from commercial jetliners. The sensors, developed jointly by NASA and AirDat LLC of Raleigh, NC, measure temperature, relative humidity, winds aloft, turbulence, and icing, and report these to the ground in real-time. The sensors were originally deployed as part of the Great Lakes Fleet Experiment conducted by the National Weather Service. In addition to the Mesaba fleet, in August 2008 data were added for Chautauqua airlines, which has about 60 aircraft, with geographic coverage from the Gulf Coast to the Northeast U.S.
The aircraft dataset is organized in two different ways: the "Aircraft-Based Reports" files contain all of the data, while the "Profiles at Airports" files only have data taken from aircraft taking off and landing at airports, which are organized into profiles associated with the location of the airports. Note that all of the data in the profiles are also contained in the Aircraft-Based Report files. Therefore users whose applications do not need the data organized into profiles only need to get the Aircraft-Based Report files.
Geographic CoverageCurrently-participating U.S. airlines are: American, Delta, Federal Express, Northwest, United, United Parcel Service, and Mesaba. In addition, the following airlines participate in the AMDAR program: BA, KLM, Air France, SAS, Lufthansa, Qantas, Air New Zealand, South African Air, Air Namibia.
Approximately 140,000 wind and temperature observations are available per day, 100,000 of which are over the continental United States. These data come from more than 4000 aircraft. There are more data during the daytime than at night, but thanks to participation by some parcel-carrying airlines, nighttime coverage is substantial.
Click here for a map showing the geographic coverage of the aircraft data over the 3-hour period 1200 - 1500 UTC on 19 September 2001.
Data ScheduleData arrive more or less continuously (with more during the day, as stated above), and are processed every 10 minutes. The data are segmented into hourly files, with the file for hour HH containing data for HH00 through HH59. Some reports arrive late, so each hour's data is reprocessed a number of times. The most complete data for a given hour is available about 13 hours after the file time. Using hour 00 as the example, the file is processed and available at around 0023, 0033, 0043, 0053, 0103, 0113, 0123, 0138, 0223, 0323, 0933, 1333.
VolumeTypical daily volume for all MADIS datasets can be seen here.
RestrictionsData that is 48 hours old and older are publicly accessible. All data less than 48 hours old are restricted based on the following rules ("real-time" is defined as less than 48 hours old):
- Real-time ABO data may be made available to those organizations that are performing research which, in the judgment of MADIS Support, is likely to benefit the airlines providing the data.
- The data may not be redistributed in real-time. However, the use of images in research publications is allowed and encouraged.
- Researchers are encouraged to use ABO data in Numerical Weather Prediction models. NWP model results may be made available to the public in real-time provided that all of the following conditions are met (Adapted 26 April 2001):
- Individual ABO measurements may not be revealed (though gross numbers may be).
- ABO must be one of several kinds of input observations (such as radiosondes and METARs).
- The model and data may not be used to develop products or services for sale.
- Real-time data are available to government agencies such as NOAA in support of forecasting operations.
- Real-time data may be made available only to those airlines that provide Aircraft-Based meteorological data to the US Government at their own expense. Data may not be shared with affiliate or code-share airlines. (Language clarified 26 April 2001.)
- Real-time data may not be made available to commercial entities that would use them to develop products or services they plan to offer for sale to the participating airlines.
- ESRL/GSD's Aircraft Data Web
Information on the ESRL/GSD decoder and its processing.
The home page of Aeronautical Radio, Inc.
- Water Vapor Sensing System Program
Information on the moisture observations available with some ACARS reports.
The home page of the European AMDAR effort.
Last updated 5 August 2015