NOAA: Health of Earth at worst levels
Report blames carbon emissions, says gains made during pandemic erased
A fatal virus and a massive economic downturn did not stop planet-warming gases in the atmosphere last year from rising to their highest levels in human history, researchers say. Barely a year after the coronavirus grounded planes, shuttered factories and brought road traffic to a standstill, the associated drop in carbon emissions is all but undetectable to scientists studying our air.
In fact, according to the newly released “State of the Climate in 2020” report from the National Oceanic and Atmospheric Administration, Earth is arguably in worse shape than it’s been.
While humanity grappled with the deadliest pandemic in a century, many metrics of the planet’s health showed catastrophic decline in 2020. Average global temperatures rivaled the hottest. Mysterious sources of methane sent atmospheric concentrations of the gas spiking to unprecedented highs; sea levels were the highest on record; fires ravaged the American West; and locusts swarmed across East Africa.
These findings may sound familiar, coming on the heels of a similarly dire assessment from the United Nations Intergovernmental Panel on Climate Change. And they echo NOAA’s report from last year, which also detailed record-high greenhouse gas levels and unprecedented warmth.
“It’s a record that keeps playing over and over again,” said Jessica Blunden, a NOAA climate scientist who has co-led “State of the Climate” reports for 11 years. “Things are getting more and more intense every year because emissions are happening every year.”
Sometimes Blunden feels like a doctor whose patient won’t listen to health advice, watching a mild illness morph into a chronic disease. By this point, the patient practically has multiple organ failure; “and still they keep eating those Cheeto puffs,” she said.
Without consistent, concerted efforts to reduce emissions from burning fossil fuels and other human activities, scientists warn, Earth’s condition will continue to deteriorate.
NOAA’s assessment, published this week in the Bulletin of the American Meteorological Society, draws on the work of 530 scientists from 66 countries.
In the atmosphere, the researchers found no evidence that last year’s 6 percent to 7 percent dip in global annual emissions had any lasting effect. The roughly 2 gigatons of carbon dioxide not emitted during the most severe pandemic-related shutdowns have been dwarfed by the more than 1,500 gigatons humans have unleashed since the Industrial Revolution began.
As Glen Peters, a scientist at the Center for International Climate Research, put it on Twitter: “The atmosphere is like a (leaky) bathtub, unless you turn the tap off, the bath will keep filling up with CO2.”
The average concentration of carbon dioxide in the atmosphere in 2020 was 412.5 parts per million, about 2.5 ppm above the 2019 average. That is higher than at any point in the 62 years scientists have been taking measurements. Not even air bubbles trapped in ice cores going back 800,000 years contain so much of the gas, suggesting current levels have no precedent in our species’ history.
Carbon dioxide typically lingers in the atmosphere for a few hundred to 1,000 years. Humans will have to stop emitting for much longer than a few months to make a meaningful dent in concentrations of the pollutant.
Even as carbon dioxide emissions briefly slowed, 2020 saw the largest annual increase in emissions of methane. The gas only stays in the atmosphere for about a decade but can deliver more than 80 times as much warming as carbon dioxide in that time frame.
Scientists don’t know why the concentration of methane spiked so dramatically — rising 14.8 parts per billion to its highest level in millennia. The drilling and distribution of natural gas helps drive up methane emissions. But it is also produced by munching microbes, which are found in both natural environments such as wetlands, and human-built ones such as landfills and farms.