Half to two thirds of the world’s oxygen come from photosynthetic plankton (phytoplankton) in the ocean.
The oceans are getting hot. The heat means less oxygen, as it kills off the ocean’s phytoplankton. These organisms not only produce oxygen for the planet, but function as the base layer of the ocean’s biosphere. Krill eat the plankton, fish eat the krill, birds and dolphins eat the fish.
Eliminating this base layer in the food web absolutely destroys all other population groups.
Since 1950, it’s estimated that phytoplankton populations have declined by about 1% per year. This averages out to about 40% since 1950.. With this comes a decrease in the populations of krill. A reduction in the population of krill translates to a reduction in fish populations. This then makes it more difficult for the predators of that fish (birds, whales) to survive.
As ocean waters warm, the photoplankton move to cooler areas.. As PS Mag reports:
In 2015, Barton and a team of fellow oceanographers tracked environmental changes like temperature and salinity to approximate where phytoplankton will migrate over the course of the next century. They predict that phytoplankton along the North Atlantic coast will migrate toward cooler waters off the coast of Greenland, lessening the food source for fish and other marine life.
Should the oceans continue to warm at their current rates, by 2100, they could almost completely die off.
Should humans continue to survive in such a world, we’ll be doing so alone. The life on this planet is the only other form of life we know of in the universe. We share this planet with them, and it’s our moral responsibility to do so as shepherds. Not as sociopathic consumers of the planet’s resources, for the sole goal of capitalist profit.