Barrow observatory catches clean Arctic air
About 5 miles north of Alaska’s northernmost community, Utqiagvik, is the Barrow Atmospheric Baseline Observatory.
According to Peter Detwiler, technician at the Barrow Observatory, “it started in 1973 to measure CO2, greenhouse gases and solar radiation and aerosols in the beginning as well as ozone.”
This location was chosen because it is the northernmost point in the U.S. This means most of the time, the air the observatory collects is coming off the Beaufort Sea or the tundra with very little human interaction. “We're getting the cleanest air we can possibly get to make our baseline measurements,” says Detwiler.
The Barrow facility is one of four baseline observatories that make up NOAA’s Global Monitoring Division. The other locations are the South Pole, American Samoa and Mauna Loa in Hawaii. Though the four facilities are far apart, they are seeing similar patterns.
“At the Barrow site and the other baseline sites are seeing a steady increase in CO2,” says Detwiler.
The carbon dioxide trend lines from all four sites trend upward but Barrow’s line looks a little different from the others, showing more dramatic highs and lows even as the pattern tilts higher.
“Barrow, as well as other northern hemisphere sites, have more seasonal fluctuations because of all the vegetation that exists up here,” Detwiler says.
In spring and summer, plants absorb carbon dioxide which draws it out of the air. Once the snow and ice cover the ground, the CO2 level rises.
At the dawn of the industrial era, CO2 levels were estimated at 280 ppm.
All four sites rose above 400 ppm of CO2 between 2012 and 2016 for the first time since measurements began.