One thing you have to say for Donald Trump. He manages to suck all the oxygen out of a room.
This post happens to be about oxygen and it isn't about Trump, not directly. It's a report that came out last week that, as these studies tend to do, is about to vanish down the memory hole. It's a horror story or it should be if we had our wits about us. We don't.
The report is about oxygen, specifically how it is disappearing from our oceans and creating dead zones. The study finds that the number of these dead zones has quadrupled since 1950. These anoxic waters have expanded by millions of square miles in just our lifetimes. But wait, there's more. Along our coasts these dead zones have increased ten times. Not four, ten.
"Oxygen is fundamental to life in the oceans," said Denise Breitburg, lead author and marine ecologist with the Smithsonian Environmental Research Center. She's part of the GO2NE (Global Ocean Oxygen Network), which was founded in 2016 to tackle this problem.
"The decline in ocean oxygen ranks among the most serious effects of human activities on Earth's environment."
While scientists have long been aware of these dead zones, this is the first review paper to take such a broad, global view of the issue. And the results aren't pretty.
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As Earth's climate continues to warm, the team predicts that the oceans will continue to lose oxygen at a rapid pace.
And, as the paper in the journal Science points out: "Major extinction events in Earth's history have been associated with warm climates and oxygen-deficient oceans."
So what's causing these dead zones?
Climate change is a huge part of the problem, especially for the open ocean. Because warm water holds less oxygen, as surface water temperatures warm up, it makes it harder for oxygen to get down into the depths of the ocean.
Closer to shore, nutrient pollution - such as the runoff from agricultural practises - is also playing a big role.
Nutrients like phosphorous from fertiliser can easily end up in rivers and estuaries, which creates algal blooms that drain oxygen from the water as they die and decompose.
It's no surprise then that scientists are worried about the algae bloom the size of Mexico in the Arabian Sea.
Unfortunately, as the oceans get warmer, marine life actually needs more oxygen to survive, not less. The result is huge patches of bleached coral and dead marine life.
Here's a chart depicting our suffocating oceans.
First, the world warms over short intervals of time because of a sudden increase of carbon dioxide and methane... The warmer world affects the ocean circulation systems and disrupts the position of the conveyor currents. Bottom waters begin to have warm, low-oxygen water dumped into them. Warming continues, and the decrease of equator-to-pole temperature differences reduces ocean winds and surface currents to a near standstill. Mixing of oxygenated surface waters with the deeper, and volumetrically increasing, low-oxygen bottom waters decreases, causing ever-shallower water to change from oxygenated to anoxic. Finally, the bottom water is at depths were light can penetrate, the combination of low oxygen and light allows green sulfur bacteria to expand in numbers and fill the low-oxygen shallows. They live amid other bacteria that produce toxic amounts of hydrogen sulfide, and the flux of this gas into the atmosphere is as much as 2,000 times what it is today. The gas rises into the high atmosphere, where it breaks down the ozone layer, and the subsequent increase in ultraviolet radiation from the sun kills much of the photosynthetic green plant phytoplankton. On its way up into the sky, the hydrogen sulfide also kills some plant and animal life, and the combination of high heat and hydrogen sulfide creates a mass extinction on land. These are the greenhouse extinctions.
And what is our political response to this? Close to nil. The oceans, with their ability to suck vast quantities of heat and CO2 from the atmosphere and as the handy dumping ground for our waste, including agricultural chemical runoff, are a political "get out of jail free" card, for now.
Unfortunately, our oceans bat last. In recent decades prevailing wind patterns have caused the oceans to absorb enormous amounts of heat energy that has been carried into the depths. That's where the first law of thermodynamics comes into play, the one that tells us that energy can neither be created nor destroyed, just converted from one form into another. So all that heat carried into the depths of the ocean, well it's coming back up and it will be returned to the atmosphere.
Climate change is like a prize fight. It's not how you take a punch but how you absorb a flurry of punches. The ocean is absorbing what we're dealing out - the extra heat, the acidification, the chemical contamination - but we are not prepared for its counter-punching. You can be hundreds, thousands of miles from the ocean, drylanders in Toronto or Winnipeg or Calgary. It makes no difference. The ocean will reach you.
Paleontologist Peter Ward of the University of Washington in his book, "Under a Green Sky," has a one-paragraph description of what happens when absorbed CO2 crosses the oceanic tipping point:
Well, Jeebus, if we knew that we would deal with it, wouldn't we? Surely we would never let that happen, not if we knew better. It's time for that godawful reality check. We do know. We know better. It's all good, old-fashioned, evidence based, tested and verified science. It's all there at the fingertips of every government on Earth. And no, we aren't going to deal with it. We are letting it happen. We are unleashing this fate on future generations.
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