ESRL Global Systems Division

Revolutionary Air Profiling System Parachuted from Balloon at 72,000 ft

A team of NOAA/ ESRL scientists from the Global Monitoring Division (GMD) and the Global Systems Division (GSD) recently completed the third successful stratospheric balloon flight, testing the AirCore™ atmospheric gas concentration profile sampler. The AirCore™ consists of a 250 ft. thin-walled, stainless steel coil of tubing that is open and subsequently fills with air as the coil is parachuted to the ground. During the descent, a so called "noodle of air" flows into the tube and maintains a record of gas concentrations at various altitudes. The air is analyzed by pushing it out of the tube into an analyzer with a "push" gas. "Because of its simple design, operation, and low cost, the AirCore™ is a breakthrough in atmospheric gas concentration profiling," says Pieter Tans, group leader of the ESRL Carbon Cycle and Greenhouse Gas group.

Atmospheric profiling of trace gases is presently accomplished by flying an aircraft with in situ samplers or collecting bottles of air during aircraft profiles. Both methods are expensive and provide limited altitude information as most sampling aircraft cannot fly above 30,000 ft. The Aircore™ weighs only 16 pounds and can be carried aloft with inexpensive meteorological balloons conducting up to 25 profiles with essentially expendable equipment for the price of one high-altitude aircraft sampling flight.

This latest balloon flight was conducted jointly by ESRL and the Edge of Space Science (EOSS) Balloon Group, a Colorado educational non-profit corporation for promoting science and education through amateur radio and high-altitude balloon flights. The balloon was launched and cut down by radio command from the EOSS ground station at Windsor, CO. with the payload landing some 30 miles away entangled in a power line. The AirCore™ was recovered and returned the same day for trace gas analyses at ESRL laboratories in Boulder.

The initial analyses show that CO2 is not uniformly distributed through the atmosphere, as has generally been believed. Figure 1 shows the profile of CO2 distribution with altitude plotted with temperature. Note in Figure 2, showing the CO2 and relative humidity profiles, that AirCore™ worked well even as it descended through a cloud (between 8 and 10 km).

AirCore profile
Fig. 1: AirCore™ profile of CO2 and air temperature.

AirCore profile
Fig. 2: AirCore™ profile of CO2 and relative humidity.

ESRL has submitted a patent application for the AirCore™ because of its enormous potential to obtain numerous profiles of trace gases on a global scale. The AirCore™ could feasibly collect 1000 or more profiles inexpensively on a daily basis around the world as it can be easily deployed on commercial and private aircraft, from Unmanned Aircraft System platforms, or carried aloft with small balloons. The AirCore™ team on the just completed flight consisted of Pieter Tans, Aaron Watson, and Colm Sweeney of GMD, and Russell Chadwick and Randy Collander of GSD.

Contact information
Name: Russell B Chadwick
Tel: 303 497 6318