Tag: CO2

How long can the oceans soak up CO2?

What’s the tipping point?

Researchers examine ocean acidification rates

Staff Report

For now, the world’s oceans are sucking up so much carbon dioxide that it’s helping to slow the rate of global warming. But that’s expected to change in the future, researchers warned after taking a detailed look at the rate of ocean acidification in the northeast Pacific Ocean. Continue reading “How long can the oceans soak up CO2?”

Forests may not benefit from rising CO2 levels

Intense aspen and scrub oak color in this aerial view of Eagle County, Colorado.
Aspen and scrub oak forests in western Colorado. @bberwyn photo.

Study says disastrous tipping points could be reached by 2050

Staff Report

Forests of the future may not be able to remove heat-trapping CO2 from the atmosphere as effectively as previously thought, scientists said in a new study that’s based on an extensive analysis of tree ring data from the past.

“We utilized a network of more than two million tree-ring observations spanning North America. Tree-rings provide a record into how trees that grow in different climates respond to changes in temperature and rainfall,” said Brian Enquist, a professor in the UA’s Department of Ecology and Evolutionary Biology and a fellow of the Aspen Center for Environmental Studies in Aspen, Colorado.

The research challenges assumptions about how forests will respond to warmer average temperatures, increased greenhouse gas emissions, and shifting rainfall patterns. It also suggests that the warming climate already is rapidly pushing many forests towards an ecological tipping point, which may be reached as early as 2050, Exposure to unprecedented temperatures hampers tree growth and makes them susceptible to other stress factors. Continue reading “Forests may not benefit from rising CO2 levels”

How much CO2 will melting permafrost release?

Highway to the West Fjords region of Iceland
The warming of the world’s tundra and permafrost areas will have a huge effect on global climate. @bberwyn photo.

New study shows soil moisture is a big factor in global warming equation

Staff Report

Methane won’t be the only problem as Arctic permafrost thaws in the coming decades. A new study shows that, as frozen permafrost areas warm and dry out, they will also release more CO2. The study was led by Northern Arizona University assistant research professor Christina Schädel and published in the journal Nature Climate Change.

The findings show that a 10 degree Celsius increase in soil temperature released twice as much carbon into the atmosphere, and drier, aerobic soil conditions released more than three times more carbon than wetter, anaerobic soil conditions. Continue reading “How much CO2 will melting permafrost release?”

Annual atmospheric CO2 increase the biggest on record

Far, far away from 350 ppm …

Atmospheric carbon dioxide in February 2016 measured at Mauna Loa.
Atmospheric carbon dioxide in February 2016 measured at Mauna Loa.

Staff Report

The goal of limiting atmospheric carbon dioxide to 350 parts per million — considered the environmentally “safe” level, just moved a little farther away. Scientists tracking concentrations of the heat-trapping pollutant at a mountaintop lab in Hawaii said last week that CO2 concentrations jumped by the largest annual amount recorded since measurements began 56 years ago.

The reading comes from NOAA’s Mauna Loa Observatory, and researchers said the latest increase was the fourth year in a row that CO2 concentrations grew by more than 2 parts per million, according to a press release from NOAA.

“Carbon dioxide levels are increasing faster than they have in hundreds of thousands of years,” said Pieter Tans, lead scientist of NOAA’s Global Greenhouse Gas Reference Network. “It’s explosive compared to natural processes.” Continue reading “Annual atmospheric CO2 increase the biggest on record”

Study says ocean acidification has already slowed coral growth

A diverse coral reef in the U.S. Virgin Islands. PHOTO BY CAROLINE ROGERS/USGS.
A coral reef in the U.S. Virgin Islands. Photo by Caroline Rogers/USGS.

‘If we don’t take action … coral reefs will not survive into the next century’

Staff Report

The most dangerous effects of global warming may still be decades away, but ocean scientists say that the buildup of carbon dioxide is already slowing down the growth of coral reefs. By simulating ocean acidification on a section of the Great Barrier Reef, the researchers showed that excess C02 in the atmosphere is affecting coral reefs.

“Our work provides the first strong evidence from experiments on a natural ecosystem that ocean acidification is already causing reefs to grow more slowly than they did 100 years ago,” said study lead author Rebecca Albright, a marine biologist in Carnegie’s Department of Global Ecology in Stanford, Calif. “Ocean acidification is already taking its toll on coral reef communities. This is no longer a fear for the future; it is the reality of today.” Continue reading “Study says ocean acidification has already slowed coral growth”

Antarctic ice sheets may be more sensitive to CO2 than we thought

New ice core study helps pinpoint global warming impacts

Ice core samples suggest that Antarctic ice sheets may see big changes at lower levels of CO2 than previously thought. @bberwyn photo.

Staff Report

After studying a new ice core sample from McMurdo Sound, researchers say they’re a bit closer to one of the holy grails of climate science — understanding how Antarctic ice sheets will respond to increasing concentrations of atmospheric carbon dioxide.

The study, published in the Proceedings of the National Academy of Sciences, suggests that big changes could happen at lower levels of CO2 than previously thought.

The scientists looked at a 3,735-foot sediment core to reconstruct the Antarctic ice sheets’ history in an effort to create a climate model that mirrors conditions during the Miocene Era, when atmospheric CO2 levels were slightly higher, at 500 parts per million, than the 400 ppm level reached just last year, and global average temperatures were about 3 to 4 degrees Celsius higher than today. Continue reading “Antarctic ice sheets may be more sensitive to CO2 than we thought”

CO2 could take huge toll on ocean fish by mid-century

Can the world’s oceans survive the global warming era?

Not much time left to cut greenhouse gas pollution

Staff Report

Building levels of carbon dioxide in the atmosphere and oceans could have a widespread and devastating effect on many fish by 2050, Australian researchers warned in a new study.

“Our results were staggering and have massive implications for global fisheries and marine ecosystems across the planet,” said Dr. Ben McNeil, a researcher at the University of New South Wales Climate Change Research Centre. “High concentrations of carbon dioxide cause fish to become intoxicated … a phenomenon known as hypercapnia. Essentially, the fish become lost at sea. The carbon dioxide affects their brains and they lose their sense of direction and ability to find their way home. They don’t even know where their predators are,” McNeil said. Continue reading “CO2 could take huge toll on ocean fish by mid-century”