NOAA and United Airlines announced an agreement today to equip a Boeing 737 with sophisticated instruments that will measure greenhouse gases and other pollutants during domestic flights. It’s a first step in establishing a partnership that could significantly improve monitoring of carbon dioxide, methane and other greenhouse gases, as well as improving the accuracy of weather forecasts in the United States. 

The multi-year agreement is designed as a test for a potential larger network of instrumented commercial aircraft that would allow for continual monitoring of pollutants and greenhouse gases above U.S. cities. The agreement was announced today at the White House Super Pollutants Summit in Washington, D.C.

"This collaboration represents a significant leap forward in U.S. efforts to monitor and mitigate greenhouse gas emissions," said Sarah Kapnick, NOAA’s chief scientist. "If we can harness the capabilities of commercial aircraft, we will be poised to make rapid advancements in the understanding of greenhouse gas emissions that can inform policies."

CIRES scientists in NOAA’s Global Monitoring Laboratory are contributing to the project in several ways. They are modifying instruments so that they can operate untouched for months at a time while installed in a commercial aircraft; adding a computer to the suite of instruments that can record parameters like latitude, longitude, and altitude so scientists know where the aircraft is when the measurements are taken; and designing a system to retrieve the data remotely. CIRES scientists will also help analyze the data once the measurements have been quality controlled.

In-flight sampling of the atmosphere

NOAA’s Global Monitoring Laboratory operates a network of 60 air sampling sites around the world, and contracts with private pilots to collect airborne samples during 14 regular flight routes in the U.S. an average of three times a month. Analysis of these samples provides data that allows scientists to accurately track the global increase in carbon dioxide and other greenhouse gases, which they incorporate into NOAA’s Global Greenhouse Gas Reference Network, one of the foundational research tools used by climate scientists.

In addition to taking measurements at stationary sampling sites, NOAA and other federal agencies regularly conduct research missions to make direct measurements of greenhouse gases and air pollutants from aircraft, but these campaigns are costly and limited in terms of how much area they can cover and how long the instruments remain in the air. Installing instruments on commercial airliners would vastly increase the number of samples researchers could analyze.  

“We’ll be collecting data over multiple cities multiple times a day, in different seasons, and under varying weather conditions,” said Colm Sweeney, who leads the Global Monitoring Laboratory’s commercial aircraft program. “This will allow scientists to more accurately measure U.S. emissions at sub-regional scales, which is one goal of a national greenhouse gas monitoring strategy announced earlier this year, and at just 1 percent of the cost of deploying research aircraft,” Sweeney said. 

Combining measurements from instruments on commercial aircraft with satellite observations would create a continuous air pollutant monitoring system in the United States. By certifying this instrument set for the Boeing 737, flown by airlines throughout the world, other countries will be able to quickly adopt this technology for their own climate monitoring. 

“This new partnership with United is the first step in establishing a Commercial Aircraft Greenhouse Gas Monitoring Program which will add valuable greenhouse gas measurements near large urban areas where most of greenhouse gas emissions originate,” said Vanda Grubišić, director of the Global Monitoring Laboratory. 

The greenhouse gas data will make a major contribution to the new U.S. Greenhouse Gas Center, an effort led by NASA, EPA, NIST, and NOAA to aggregate existing and new scientific information to better understand greenhouse gas cycling by human-caused and natural processes, she added.