With both the US and China having ratified the Paris agreement, the possibility genuinely exists that we may be able to protect our planet from the worst ravages of climate change. However, there’s a natural phenomenon at play that has already been saving the world for some time now – the oceans.
The oceans are collectively a carbon sink, an absorber and storage cache for carbon dioxide, along with the atmosphere, forests, soil, and rocks. A new report by the International Union for Conservation of Nature (IUCN) highlights the fact that the world’s waters are the most potent carbon sink by far, having absorbed over 90 percent of the extra heat generated by human activity.
In fact, without the oceans – which cover 70 percent of our planet’s surface – Earth would have warmed far more than the 1°C (1.8°F) that's occurred in modern times. Citing a previous study, the report explains that "if the same amount of heat that has gone into the top 2000 meters of the ocean between 1955-2010 had gone into the lower 10 kilometers of the atmosphere, then the Earth would have seen a warming of 36°C (64.8°F)."
At present, the rate of temperature change is ten times greater than what would be expected from a post-glacial period recovery, and already our species faces more potent natural disasters, agricultural failure, cryosphere destruction, economic collapse and accelerated sea level rise. Without the oceans, then, the world would have been literally scorched long ago in a self-made conflagration.
“Up until now, the ocean has shielded us from the worst impacts of climate change,” the report concludes. “We perhaps haven’t realized the gross effect we are having on the oceans, we don’t appreciate what they do for us.”
The report points out that although the oceans may have barricaded the surface world from a climate change apocalypse, the life within the oceans themselves is already suffering. The biodiversity underwater is second to none, with enormous marine mammals sharing space with the smallest of plankton.
The absorption of carbon dioxide may be saving us in the short-term, but it will warm the oceans as much as 4°C (7.2°F) by 2100, as well as making them incredibly acidic. Everything, from apex predators to symbiotic coral reefs, will suffer, unable to keep up with this extraordinary rate of change. Billions of people who rely heavily on fish for subsidence will ultimately lose out as food chains begin to collapse.
Many in southeast Asia will be heavily impacted by the loss of fish over the next century. Jimmy Tran/Shutterstock