Up to 90 percent of the warming caused by human carbon emissions is absorbed by the world's oceans, scientists estimate. And researchers are increasingly agreeing that the oceans are warming up faster than previously thought.
Several studies in recent years have found that previous estimates of the intergovernmental group on climate change may be too low. A new review of the research, published yesterday on Science concludes that "multiple lines of evidence from four independent groups now suggest a stronger warming observed [ocean heat content]."
Overall, the research suggests that the oceans are overheating about 40% faster than previously estimated by the IPCC. Since the 1
While much of the human concern about climate change focuses on its effects on increasing land air temperatures, changes in weather patterns and accurate estimates of ocean warming are of paramount importance for understanding by global warming scientists. Determining the speed at which the oceans are heating helps scientists to calculate how sensitive the planet is to greenhouse gas emissions and how quickly it will heat up in the future.
"The ocean, in many ways, is the best thermometer we have for the planet," said Zeke Hausfather, climate scientist at the University of California, Berkeley, and co-author of the new analysis.
Accelerated warming is also a major concern for ocean ecosystems, bringing coral bleaching events to the earth around the world and forcing some species to migrate to colder waters. Heating also increases ocean water, which can contribute to sea level rise.
For nearly two decades, scientists have been using a floating network throughout the ocean to constantly monitor water temperatures around the world. But before the early 2000s, when the network was launched, scientists relied primarily on measurements taken by passing ships as they made their way across the seas. This meant that observations on oceanic temperatures around the world were rarer and that scientists had to use statistical methods or models to fill the gaps.
In recent years, improved data from the mobile network and improvements in statistical models and tools used to analyze previous measurements have helped scientists develop more accurate ocean warming reconstructions in the last century.
As the new review reports, several studies now agree that the oceans are warming up at a faster rate than suggested by the older estimates. And these revised calculations adapt better to climate model simulations than previous estimates, giving scientists more confidence that the model's projections for the future are on track.
And if the models are accurate, continuing to emit greenhouse gases at the current rate could lead to dire consequences for the global oceans. As the new analysis points out, the models suggest that a business-as-usual climate scenario could cause about 1.5 degrees of ocean warming – the equivalent of almost one foot of rising sea levels by the end of the century . Being able to achieve the climate goals of the Paris Agreement, on the other hand, could halve heating.
Scientists are not only interested in how much heat the oceans are absorbing. As the heat moves around the planet it can reveal important clues to how high the seas can rise in different places, for example.
Another study, published earlier this week in Proceedings of the National Academy of Sciences also concluded that the oceans absorbed at least 90 percent of the excess heat in the area. atmosphere. He also found that they have been heating at least since the end of the 1800s, although his estimates for the heating rate may be somewhat lower than those suggested by some of the recent studies.
The study suggests that the oceans "currents and large-scale circulation patterns have changed in recent decades – for reasons scientists are still studying – and that these changes are affecting places where oceanic heat ends.  The study suggests that up to half of the extra heat accumulated in the mid-Atlantic regions of the Atlantic Ocean since the 1950s was actually being transported there from other parts of the ocean. raising heat sea level in this part of the ocean is influenced by changing patterns of circulation.
It is important to pay attention, the researchers note, because future climate change can cause even greater changes in ocean currents, many of which are heavily influenced by winds and atmospheric patterns that can be affected by global warming nictitating these changes could help scientists predict which parts of the ocean will overheat and expand, the fastest in the future.
"Future changes in ocean transport could have serious consequences for sea level rise at the regional level and the risk of coastal flooding," the authors write.
Reprinted by Climatewire with permission from E & E News. E & E provides daily coverage of essential energy and environmental news on www.eenews.net.