Since 1901, the surface temperature of our oceans has risen at an average rate of .13 degrees fahrenheit per decade. As the water continues to heat up, the atmosphere does not receive as much oxygen due to the oceans mixing at a far lower rate. In fact, a study conducted in the science journal Nature indicated that the oxygen level has been reduced by more than 2% between 1960 and 2010, with the North Pacific Ocean and Artic Ocean seeing as much as a 4% drop in that time period. Due to global warming, the decreased oxygen levels pose a threat to not only marine animals, but to humans as well.

A Decrease in Earth's Oxygen Supply

Drastic temperature increases like what we've seen can result in potentially hazardous conditions for our atmosphere. Gas levels in the ocean are controlled in part by the temperature of the sea. The list of gases include oxygen, which is responsible for as much as 85% of the world's supply. In order to de-gas water, you must make it's temperature rise. Much like when boiling water for your spaghetti - as the ocean's water heats up, essential gases like nitrogen, carbon dioxide, and oxygen that would have been made by the sea is lost. As boldly stated by Ron Dunbar, Stanford University, “Anything with a gill is going to care and notice.”

As such, the global warming of our oceans do not just affect marine life, but can result in a loss of key gases that humans use to live on this planet.

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How will this affect Marine Animals?

The reduction of oxygen is not spread evenly throughout the oceans, but primarily affected in specific areas of the world. Particular pockets will have far less oxygen than the others, which has a profound impact on marine life in terms of migration patterns, feeding grounds, and even areas to reproduce. David Baker, Assistant Professor at the University of Hong Kong’s Swire Institute of Marine Sciences asserted, “Just a little loss of oxygen in coastal waters can lead to a complete change in ecosystems -- a small decrease in oxygen like this can transform from something desirable to very undesirable.” Eventually we may see behavioral changes for larger marine animals, such as sharks, who expend more energy than smaller marine animals when performing particular activities like hunting and feeding. If their normal feeding grounds are unable to provide enough oxygen, they may adapt and migrate elsewhere - which in turn can change local ecosystems with a new variety of marine life.

If humanity continues along this path of ignoring the climate change, the unfortunate truth is we will soon begin to see this harsh reality with deep sea creatures in the coming decades. As oxygen enters the ocean at the surface, warmer waters will make it less likely for it to reach the lower levels of the sea. Additionally, with the reduction of sea ice, there will be a rise in plankton decomposition that will add a compound effect as the decomposition also decreases oxygen levels.

3 Solutions Consumers an Adopt

Adopt Green-Energy Solutions - The increase of utility companies that obtain their power wind or solar have increase dramatically, and as consumers we have the ability to start making an impact by choosing to have our homes use these companies. The more humanity adopts these companies as their primarily utility provider, the closer we get to a green-house gas free world.
Reduce Wasting Water - By not wasting water, we are able to reduce carbon pollution as it takes quite a bit of energy to treat and maintain a household's flow of clean water.
Use LED Lightbulbs - LED Lightbulbs use up to 80 percent less energy than traditional incandescents, resulting in a much lower energy usage.

Overall, humanity has a long way to go to rectify the current trajectory of our climate, but through consumer support and continued adoption of fuel-efficient vehicles, utilities, and waste reduction awareness - we are steps to keeping our planet healthy.

Bibliography:

Suffocating the Sea: How Global Warming is Reducing the Ocean's Oxygen Supply

A Decrease in Earth's Oxygen Supply

How will this affect Marine Animals?

3 Solutions Consumers an Adopt