Permafrost and wetland emissions could cut 1.5C carbon budget ‘by five years’

Permafrost and wetland emissions could cut 1.5C carbon budget ‘by five years’

SOURCE: Carbon Brief DATE: July 9, 2018 SNIP: Emissions of CO2 and methane from wetlands and thawing permafrost as the climate warms could cut the “carbon budget” for the Paris Agreement temperature limits by around five years, a new study says. These natural processes are “positive feedbacks” – so called because they release more greenhouse gases as global temperatures rise, thus reinforcing the warming. They have previously not been represented in carbon budget estimates as they are not included in most climate models, the researchers say. The findings suggest that human-caused emissions will need to be cut by an additional 20% in order to meet the Paris Agreement’s 1.5C or 2C limits, the researchers estimate. … The researchers then used the model to simulate the response of permafrost and natural wetlands to climate change. When the additional CO2 and methane emissions are incorporated, the available carbon budget shrinks substantially – falling to 533bn-753bn tonnes of CO2 for 1.5C, or 14-20 years of emissions. That means accounting for the impacts of permafrost and wetlands takes around five years off the 1.5C budget. And, as the table below shows, the budgets for the 1.5C overshoot and 2C scenarios are similarly...
Fossil fuel burning set to hit record high in 2017, scientists warn

Fossil fuel burning set to hit record high in 2017, scientists warn

SOURCE: The Global Carbon Project, The Guardian, Associated Press, Earth System Science Data (PDF) DATE: November 13, 2017 SNIP: The burning of fossil fuels around the world is set to hit a record high in 2017, climate scientists have warned, following three years of flat growth that raised hopes that a peak in global emissions had been reached. The expected jump in the carbon emissions that drive global warming is a “giant leap backwards for humankind”, according to some scientists. However, other experts said they were not alarmed, saying fluctuations in emissions are to be expected and that big polluters such as China are acting to cut emissions. Global emissions need to reach their peak by 2020 and then start falling quickly in order to have a realistic chance of keeping global warming below the 2C danger limit, according to leading scientists. Whether the anticipated increase in CO2 emissions in 2017 is just a blip that is followed by a falling trend, or is the start of a worrying upward trend, remains to be seen. Estimates for 2017 put it at about 40.8 billion tons (37 billion metric tons). Sixty years ago , the world spewed only 9.2 billion tons (8.3 billion metric tons). “It’s a bit staggering,” said co-author Ralph Keeling, a Scripps Institution of Oceanography scientist, noting in an email that levels have increased fourfold since he was born in the 1950s. “We race headlong into the unknown.” The ability to monitor emissions quickly and accurately is of growing importance. The Paris agreement is based on voluntary cuts by nations, and without verification that pledges have been...
Climate ‘carbon budget’ soon maxed out

Climate ‘carbon budget’ soon maxed out

SOURCE: phys.org DATE: February 23, 2016 AUTHOR: Marlowe Hood SNIP: The window of opportunity for humanity to cap global warming by slashing greenhouse gases is closing faster than previously thought, according to a study released Tuesday. Earlier estimates of our “carbon budget”—the amount of heat-trapping carbon dioxide we can still put into the atmosphere without warming Earth by more than two degrees Celsius (3.6 degrees Fahrenheit)—have ranged from 590 billion to 2.4 trillion tonnes. The new research says the upper limit is actually half that, some 1.24 trillion tonnes of...