CO2 measurements along Continental Divide show a worrisome trend
by Allen Best
NEDERLAND, Colo. — Much as a physician’s assistant will take your blood pressure every time you visit a doctor, researchers at Colorado’s Niwot Ridge routinely measure the concentrations of carbon dioxide in the mountain air.
Results of the most recent check-up? A worrisome 414 parts per million of CO2.
The research station is located on a wind-swept spur of the Continental Divide, between the mountain town of Grand Lake and the college town of Boulder. It was established in 1967 for varied high-mountain research, including CO2 sampling.
Jim White, director of the Institute of Arctic and Alpine Research at the University of Colorado-Boulder, calls it “one of the crown jewels in the atmospheric monitoring system.” It’s at 11,300 feet in elevation, meaning it captures the well-mixed air in the troposphere. If no one site can fully capture what is happening in the atmosphere, he says, Niwot Ridge is among several that help create a big picture of what is happening with greenhouse gases in the atmosphere.
Another detail of that big picture will emerge this summer, after snow is mostly gone, when researchers again sample the air for CO2. In the Northern Hemisphere, plants draw C02 from the atmosphere, and White suspects the reading will drop to about 398 ppm. The average for the year will be somewhere between – but part of a rapid rise in the last several hundred years.
In the mid-1700s, at the start of the industrial age, the atmosphere level of C02 probably stood at around 280 ppm, scientists have concluded after studying the chemical composition of ice cores extracted from glaciers in Greenland, Antarctica, and other continents. In 1958, when direct sampling began high on the slopes of Mauna Loa, a volcano in Hawaii, atmospheric concentrations stood at 315 ppm.
C02 concentrations reflect both natural variability and the emissions, especially the burning of fossil fuels. “In general, emission rates have always gone up unless there was an economic crash of some kind,” says White. In the last few years the rate of emissions seems to have slowed for reasons not entirely clear to scientists. “But CO2 is still going up, and rapidly,” adds White.
Consider that at even the current, somewhat lower rate, global atmospheric concentrations will hit 450 ppm by the time that a baby born this year graduates from high school.
While there’s not certainty, atmospheric scientists have long said that climate systems would more seriously destabilize at around 450 ppm. Others, such as climate scientist Jim Hansen, worry about delayed effects of atmospheric concentrations, such as you might have from sleep deprivation. A few nights short of sleep, and you’re surviving—then wham, it catches up with you. This has led Bill McKibben and other environmentalists to call for dramatic action to roll back global C02 levels to 350 ppm.
Recently, Denver Post reporter Bruce Finley tagged along with researcher Jen Morse as she took an air sample on Niwot Ridge. She told him that the problem of heat-trapping greenhouse gases is understood.
“We know what it is producing emissions and we know what we have to do,” she said.
“Part of it is that everyone is so busy living their lives day to day. And we don’t have a good system in place for solving global problems. This is a global problem,” she said.