Ocean heating—which could trigger potentially devastating weather events including hurricanes and storms—is happening 40 percent faster than previous thought, scientists have warned.
And if nothing is done to slow the warming, sea levels could rise by around 12 inches in addition to that caused by melting ice, said the authors of the study published in the journal Science.
A new record for ocean warmth was set in 2018, Zeke Hausfather, a co-author of the paper and a graduate student in the Energy and Resources Group at the University of California, Berkeley, told Newsweek.
The buildup of greenhouse gasses, which stop heat from escaping the Earth’s atmosphere, is to blame for rising global temperatures, the authors said. This has in turn led to the devastation of the natural environment including destroyed coral reefs, the depletion of oxygen levels in the ocean, as well as melting ice caps, glaciers and ice sheets in the Arctic and Antarctic.
“The rise in ocean heat content shows that the planet is clearly warming,” said Hausfather. “The prospects for much higher ocean heat content, sea level, and sea-surface temperatures should be concerning given the abundant evidence of effects on storms, hurricanes and the hydrological cycle, including extreme precipitation events.”
Hausfather said ocean heat content “is one of the main measures of climate change, with around 93 percent of all heat trapped by greenhouse gases in the atmosphere accumulating in the Earth’s oceans.”
“The ‘fingerprint’ of human influence on the climate is much easier to detect in the oceans, as it is much less affected by year-to-year natural variability than more commonly used surface temperature records,” he said.
To map heating trends, the team of scientists at the University of California analyzed the data from four existing studies on ocean warming published between 2014 and 2017.
In 2013, the United Nation’s body set up to monitor climate change, the Intergovernmental Panel on Climate Change’s (IPCC), published its AR5 report. It indicated there were discrepancies between climate models and observations of ocean heat content. “The oceans appeared to be warming notably more slowly than most models projected,” said Hausfather.
But advances in methodology over the past five years have ironed out uncertainties in earlier studies on ocean temperatures, the authors concluded.
“In our new paper in Science, we show that four updated ocean heat content estimates published in the past few years show around 40 percent faster ocean heat content warming than the estimates featured in the IPCC AR5,” said Hausfather. “These revised estimates agree well with climate model projections over the past few decades.”
“The fact that the latest observations from multiple independent groups show the same warming projected by climate models should make us more confident that our models are broadly getting the physics of the climate system right.”
Hausfather argued that understanding how the oceans heat up will help scientists pinpoint how much of the sun’s energy is trapped by greenhouse gases and how much escapes back to space.
However, he cautioned, “While it’s encouraging that four independent groups have all reached broadly the same conclusions, it may not be the final word on the matter.”
The paper comes after a study published in late 2018 indicated sea levels could rise by 50 feet by 2300 if a business-as-usual approach is taken to combating climate change.
The authors of the study published in the journal Annual Review of Environment and Resources conducted a review of existing data to arrive at their conclusion.Print This Post To toggle between English & Malayalam Press CTRL+g