Burn Notice: Sea Levels Will Rise 200 Feet If Fossil Fuels Are Not Kept in the Ground
Keep it in the ground. That’s the rallying cry of environmentalists who warn that burning the world’s remaining fossil fuel reserves would unleash catastrophic climate change.
That’s good advice, according to scientists who in a new study found that the carbon emissions from exhausting coal, oil, and natural gas reserves would melt the entire Antarctic ice sheet, triggering a sea-level rise of 160 to 200 feet.
“If we don't stop dumping our waste CO2 into the sky, land that is now home to more than a billion people will one day be underwater,” Ken Caldeira, a climate scientist at the Carnegie Institution for Science and coauthor of the paper, said in an email.
That would submerge most of Florida, Louisiana, and Texas and much of the East Coast of the United States, along with a big part of the British Isles, the European plains, and a large portion of coastal Asia, according to the study, which was published in the journal Science Advances.
The new findings are in line with the United Nations Intergovernmental Panel on Climate Change’s sea-level-rise estimates, which predict a two- to three-foot sea-level rise by 2100.
But Caldeira said that the new findings show that after 2100, sea levels would increase about 10 feet over the following 100 years. That’s nearly 10 times faster than the current rate.
“Our findings show that if we do not want to melt Antarctica, we can't keep taking fossil fuel carbon out of the ground and just dumping it into the atmosphere as CO2 like we've been doing,” Caldeira said.
Caldeira said the team took estimates under circumstances ranging from zero carbon emissions to a “burn it all” scenario—in which all 10,000 gigatons of coal, natural gas, and oil are extracted and burned over the course of 10,000 years. That worst-case scenario would lead to a global average temperature nearly 9 degrees Celsius (about 16 degrees Fahrenheit) higher than today’s temperature and much higher than the increase of 2 degrees Celsius scientists have warned we need to stay below to avoid catastrophic climate change.
Looking at the West and East Antarctic ice sheets, the researchers said the more vulnerable western sheet could become unstable within 60 to 80 years at the current rate of fossil fuel emissions. That would only require releasing 6 to 8 percent of the remaining 10,000 billion tons of potential carbon emissions locked in the ground.
“The west Antarctic ice sheet may already have tipped into a state of unstoppable ice loss, whether as a result of human activity or not,” study coauthor Anders Levermann of the Potsdam Institute for Climate Impact Research in Potsdam, Germany, said in a statement. “But if we want to pass on cities like Tokyo, Hong Kong, Shanghai, Calcutta, Hamburg and New York as our future heritage, we need to avoid a tipping in east Antarctica.”
For Caldeira the findings answered a question he and fellow scientists have been working to answer for more than 30 years: Are there enough fossil fuels in the ground to raise global temperatures to the point of melting all of the glaciers?
“Three things have changed since I first started thinking about this problem,” said Caldeira. “One; we now know that climate change is very long-lasting and it will take tens of thousands of years for climate to return to normal. Two; we now know that ice sheets can respond faster than once thought, and three; estimates of available fossil fuel resources have increased over the past decades.”