TAMDAR and the GREAT LAKES FLEET EXPERIMENT
TAMDAR stands for "Tropospheric Airborne Meteorological Data Report". An experiment is currently underway to determine the data quality of aircraft mounted atmospheric sensors providing temperature, winds and moisture. Normally, meteorological sensors of this nature can only be found attached to weather balloons, which are launched by the NWS twice per day at selected sites across the country. Successful adaptation of these sensors to commercial aircraft could produce more accurate forecasts and enhance aviation safety by providing more timely atmospheric 'soundings' to meteorologists.
Meteorological sensors have been used on commercial aircraft for many years and are referred to as ACARS data. However, these sensors do not have the ability to measure moisture, which TAMDAR sensors provide. Having the ability to provide moisture allows for a classical atmospheric sounding to be taken, similar in nature to a regular weather balloon sounding.
The Great Lakes Fleet Experiment refers to the fleet of aircraft mounted with TAMDAR sensors currently involved in the test. Mesaba Airlines is hosting the units on their SF340 turboprop fleet. A picture of an SF 340 is shown below. Mesaba is a feeder airline to Northwest, and serves their hubs at Minneapolis, Detroit and Memphis. Therefore, most of the data will be concentrated around those three cities. And in case you're wondering, Memphis has not been moved to the Great Lakes region! It was tacked on to this experiment at the last minute and became the site of comprehensive comparison testing.
The comparison testing being performed in Memphis is necessary for scientists to gage the accuracy of TAMDAR sensors as compared to standard balloon-borne sounding devices. For the purpose of the experiment, a mobile weather balloon launching facility was needed. Enter the "Aerobago", which is a converted RV equipped with a myriad of sensors and enough balloons and inflation material to complete the test. The Aerobago is currently stationed at Memphis International Airport as part of TAVE2 and will be launching comparison balloons through late May. Scientists at the University of Wisconsin and the National Weather Service will compare the data to TAMDAR and computer model output to determine accuracy. Meanwhile, operational meteorologists at many sites around the central section of the nation are able to view the TAMDAR data on the web and are evaluating it's utility to their daily forecast preparation. TAMDAR evaluation data can be viewed here.
The "Aerobago" and a balloon ready to go...
Eventually TAMDAR sensors may be added to the commercial jet aircraft fleet, which would provide a vast network of near-real time atmospheric data.