The ocean is warming much faster than previously thought, new research has found. The new study published in the journal Nature concluded that the global oceans may be absorbing up to 60 percent more heat since the 1990s than older estimates had found.
This suggests that the Earth, as a whole, is more sensitive to climate change than previous estimates would imply. And that means the planet may respond more strongly to future greenhouse gas emissions than expected.
This may have some grave implications for global efforts to meet the climate targets outlined under the Paris Agreement. Currently, world nations are striving to keep global temperatures within 2 degrees Celsius of their preindustrial levels, or a more ambitious 1.5 C if possible. If the Earth is more sensitive to climate change than previously thought, those temperature targets could approach more quickly. That means nations may have to work harder or cut emissions more quickly to stay on track.
Scientists know the ocean plays a critical role in the global climate, helping to absorb excess heat from the warming atmosphere. Oceans may store as much as 90 percent of the globe’s extra heat. There’s a strong relationship between ocean heat and the amount of dissolved gas from the atmosphere that oceans can hold. As the ocean warms, its ability to take in oxygen and carbon dioxide decreases, and more of those gases remain in the atmosphere.
Kevin Trenberth, one of that study’s co-authors, noted that the findings “have implications, because the planet is clearly warming and at faster rates that previously appreciated, and the oceans are the main memory of the climate system (along with ice loss). The oceans account for about 92% of the Earth’s energy imbalance. This is why we are having increased bouts of strong storms (hurricanes, typhoons) and flooding events.”
While the exact values of ocean heat uptake may be up for debate, more studies are all coming to the same general conclusion—that it’s a bigger problem than scientists previously thought. And that’s something to be taken seriously, the authors say.