There is more carbon dioxide than ever in the atmosphere. That’s bad for the climate
The amount of planet-warming carbon dioxide in the Earth’s atmosphere has hit a new record, as humanity struggles to rein in emissions of greenhouse gasses from burning fossil fuels.
The new record comes as tens of millions of people are grappling with extreme weather in the United States. Much of the western U.S. is experiencing the first major heat wave of the year, which is driving temperatures 20 to 30 degrees Fahrenheit hotter than what is normal for June. In the Southwest, temperatures are lingering well above 100 degrees.
Such extreme, prolonged heat is directly related to human-caused climate change, scientists say. All the extra carbon dioxide (CO2) in the atmosphere traps heat, and leads to more intense, frequent and persistent heat waves, and other extreme weather such as powerful hurricanes and heavy rain storms.
“Over the past year, we’ve experienced the hottest year on record, the hottest ocean temperatures on record, and a seemingly endless string of heat waves, droughts, floods, wildfires and storms,” said Rick Spinrad, administrator of the National Oceanic and Atmospheric Administration (NOAA), in a statement. “We must recognize that these are clear signals of the damage carbon dioxide pollution is doing to the climate system, and take rapid action to reduce fossil fuel use as quickly as we can.”
The concentration of carbon dioxide in the atmosphere is measured in parts per million, and measurements are taken at an observatory in Hawaii. In May, the atmospheric CO2 concentration peaks because the gas accumulates more in the winter months when there are fewer leaves worldwide to soak it up.
This May, the concentration of CO2 in the atmosphere hit nearly 427 parts per million, which is an increase of about 3 parts per million compared to last year’s peak. That’s one of the largest annual jumps on record, scientists say.
The vast majority of the planet-warming pollution in the atmosphere comes from humans burning fossil fuels such as oil, gas and coal.
The amount of carbon dioxide in the atmosphere has been steadily increasing since scientists began routine measurements in 1958. At that time, the CO2 concentration in the atmosphere was 313 parts per million, slightly higher than in the 19th century, when the Industrial Revolution sparked the widespread consumption of fossil fuels.
But in recent years, growth of CO2 in the atmosphere has accelerated. In the first four months of this year, the CO2 concentration increased more quickly than it has during the first four months of any previous year on record, according to scientists at NOAA and the Scripps Institution of Oceanography at the University of San Diego.
Although routine, direct measurements of CO2 in the atmosphere began in the 1950s, scientists are able to use other methods to estimate how much carbon dioxide was in the atmosphere going back millions of years. And there’s more carbon dioxide now than there has been in millions of years.
Rising CO2 levels underscore the degree to which humanity’s collective efforts to reduce greenhouse gas emissions and switch to renewable sources of energy are falling short of what would be needed to rein in global temperatures. In the U.S., greenhouse gas emissions fell slightly last year but those declines do not put the country on track to meet climate targets set by the Biden administration.
Transcript
STEVE INSKEEP, HOST:
Millions of Americans are trapped - for now - in a heat dome.
(SOUNDBITE OF ARCHIVED RECORDING)
UNIDENTIFIED METEOROLOGIST: And that has prompted excessive heat warnings and heat advisories that extend from California and Arizona into Nevada, and then eastward into Texas.
MICHEL MARTIN, HOST:
That's a meteorologist with CBS in the Bay Area. The heat dome is a big pocket of high pressure that locks in heat. It's pushed temperatures in the Southwest 20 to 30 degrees higher than normal for this time of year. And now we have news on a cause of that heat. New data shows that the planet-warming pollution that drives extreme weather has hit a new record.
INSKEEP: Rebecca Hersher, from NPR's climate desk, is covering this. Rebecca, good morning.
REBECCA HERSHER, BYLINE: Good morning.
INSKEEP: OK. What is the connection between climate change generally and this specific heat event?
HERSHER: They're intimately connected, Steve. You know, humans burn oil and gas and coal. It releases carbon dioxide and other planet-warming gases. Those gases - they accumulate in the atmosphere over the course of decades, and all of that excess gas traps heat, and that directly leads to higher temperatures worldwide. It helps drive these extreme heat events, where the temperature gets really high and stays really high - like what we're seeing. And, in fact, scientists can say that the most intense heat waves that are happening right now would be literally impossible without human-caused climate change, so it's a really close connection.
INSKEEP: OK. But our news here is that carbon dioxide levels are hitting a record. Many people who follow this are aware that the United States has been cutting its greenhouse gas emissions.
HERSHER: Yeah. That did happen, but the decrease was quite small. This was last year. And two years before that, the U.S. emissions actually increased each year. So the bigger picture here is that, you know, one - the U.S. decrease in emissions is not that big, and two - a lot of other countries are not cutting their emissions. So altogether, it's definitely not enough on its own to reverse this trend of CO2 accumulation in the atmosphere.
INSKEEP: Yeah. There is the question of the rest of the world, which is the majority of the world's people and the majority of the economic activity. So how is the carbon dioxide level measured?
HERSHER: Well, scientists continuously measure CO2 in the atmosphere, and every single year, the peak CO2 amount sets a new record because humans keep adding more CO2 faster than it can break down. This has been happening since scientists started measurements in 1958. And because scientists are able to use other methods, as well, to estimate how much CO2 was in the atmosphere going back millennia, we can actually say with confidence that there's more carbon dioxide in the atmosphere now than there has been in millions of years.
INSKEEP: In millions of years.
HERSHER: Yeah.
INSKEEP: OK, so how high is this number?
HERSHER: Well, the exact number is 426.9 parts per million of CO2 in the atmosphere. That may not sound like a lot, parts per million, but the Earth is really, really sensitive to changes in the atmosphere. A little bit of extra CO2 traps a lot of heat. What really sticks out is that this number is significantly higher than last year. It was a really, really big jump, so the amount of CO2 in the atmosphere is actually accelerating.
INSKEEP: Rebecca, thanks for the update. Really appreciate it.
HERSHER: Thanks so much.
INSKEEP: That's NPR's Rebecca Hersher. Transcript provided by NPR, Copyright NPR.
300x250 Ad
300x250 Ad