By the year 2100, all of the world's oceans and their deepest corners will be affected by a cascade of events caused by climate change, according to new research from the University of Hawaii.
This study examined how the changes will affect humans, whereas previous studies have calculated the biological and social ramifications of ocean warming. Lead author Camilo Mora and his colleagues predicted the manmade greenhouse gasses will eventually come back to affect humans.
"When you look at the world ocean, there are few places that will be free of changes; most will suffer the simultaneous effects of warming, acidification, and reductions in oxygen and productivity," Mora, assistant professor at the Department of Geography in the College of Social Sciences at the University of Hawaii (UH) at Manoa, said in a news release. "The consequences of these co-occurring changes are massive-everything from species survival, to abundance, to range size, to body size, to species richness, to ecosystem functioning are affected by changes in ocean biogeochemistry."
The affect on humans is expected to be widespread. Tourism will hurt, but food chains and fishing would cause the most damage to local economies. Less fishing means less jobs to go around, less food for communities and ultimately less economic revenue. The study found that anywhere from 470 million to 870 million people rely on the ocean for work and food.
"Other studies have looked at small-scale impacts, but this is the first time that we've been able to look the entire world ocean and how co-occurring stressors will differentially impact the earth's diverse habitats and people," said co-author Andrew Thurber, a postdoctoral fellow at Oregon State University. "The real power is in the quantitative, predictive approach using IPCC climate models that allow us to see how much it will all change, and also how confident we can be in our estimates."
More specifically, the researchers theorized the upper layer of the ocean would heat up by 1.2 to 2.6 degrees Clelsius, good for a pH decline to 0.31 from 0.15. UH's Craig Smith said these changes would harshly affect the seafloor, which would in turn hurt the rest of the ocean's environment.
"The deep-sea floor covers most of the Earth's surface and provides a whole host of important ecosystem services including carbon sequestration in seafloor sediments, buffering of ocean acidity, and providing an enormous reservoir of biodiversity," said Smith. "Nonetheless, very little attention has been paid to modeling the effects of climate change on these truly vast ecosystems. Perhaps not surprisingly, many deep seafloor ecosystems appear susceptible to the effects of climate warming over the next century."
