Ocean & Sea Life: Climate Change Impacts Beneath the Surface
9 minute read
Updated on: 14 Dec 2020
Even though our planet is called Earth, 71% of its surface is covered by water. For most of our history, the ocean has been regarded as a nearly inexhaustible resource, so large that we could never affect it. This has led us to mistreat the ocean, filling it with waste and sewage . Combined with the effects of climate change, these represent a serious threat to life in the ocean .
You probably don’t live underwater, and maybe you can imagine a diet without fish. So why should you care?
The ocean absorbs 90% of global warming
It takes much more heat energy to warm 1kg of water by 1°C than it takes to warm 1kg of air by 1°C. In scientific terms, this means water has a very high specific heat capacity.
The ocean has absorbed over 90% of the heat energy gained by the planet over the last 50 years. If this energy had been absorbed by the air in the lowest 10km of our atmosphere, we would have seen a temperature increase of around 36°C already!
Instead, all that energy has warmed the ocean. Most warming has occurred in the top 75m of the ocean surface, which gained 0.4-0.5°C in 40 years . This is much less than 36°C because of the water’s heat capacity.
But that’s not all! The ocean also stores almost 25% of the carbon we emit into the atmosphere. This storage is driven by life within the ocean , and by CO₂ dissolving in seawater .
Storing both energy and CO₂ allows the ocean to keep Earth’s climate stable despite human activities. This is known as buffering climate change .