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Good morning, John.
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Last week I joined an extremely un exclusive club of people who said that the Amazon rain forest produces 20% of the world's oxygen.
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I've since deleted it from the video because it's a fake fact.
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No one even knows where it came from.
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All of the land plants on the earth combined produce around 25% of the world's oxygen.
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The rest comes from the oceans, mostly phytoplankton, which are like teeny tiny plants.
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Except it turns out that we are imagining all of this incorrectly frame were in here indicates that if a final plankton and the plants stopped producing oxygen within a year, we would run out.
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We would not.
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We would all die immediately if there was no oh to being produced.
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That means there would be no photosynthesis.
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And photosynthesis is where all food originates so he would stop.
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Everything would die, but there would still be plenty of oxygen in the atmosphere.
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So let's do this on introduction to the carbon cycle.
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Like guess cause I, of all people should know this Lance use energy to turn carbon dioxide into carbohydrates and oxygen in a process called photosynthesis and then those carbohydrates get turned back into Seo, too, and energy, and that consumes a molecule of 02 If this happens inside an organism that's called respiration, if it happens outside an organism, it's called Combustion.
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I'm gonna lump those two together and call them both burning because I'm frustrated that there is no collective word that includes both of these things.
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Except for I guess oxidation, which is just too broad, is just one of my science communicator beef.
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We're sticking with burning fight carbohydrates are as olive garden has effectively capitalized on.
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Delicious.
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They are unstable reservoirs of energy.
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So on a geological timescale, all carbs get burned when a car gets burned.
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That molecule of 02 that the plant produced gets sucked back up every single time.
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It's a 1 to 1 cycle.
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So now you're like, OK, Hank, Yes, but like I can breathe.
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So you're wrong.
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You're right.
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I was lying to you.
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Not every carb gets burned here on land.
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Almost always, there's oxygen around to do the burn and the oceans.
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There's a fairly common exception.
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Sometimes phytoplankton come bloom so successfully that the organisms that consumed them after they die eat up all the oxygen in an area and no oxygen is left for more burning.
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The carbohydrate just falls to the bottom of the ocean, where it can never get burned.
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This process upsets the balance between CO two and oxygen.
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It's the reason I'm breathing right now.
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The photosynthesis produces that oxygen, but that oxygen doesn't get evenly distributed throughout the earth.
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So there are some areas where the burning can't happen over time.
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That results in a giant reservoir of 02 in the atmosphere.
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So if the Amazon rain forest disappeared, there would be less oxygen produced.
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But over time they would also be less oxygen consumed because oxygen consumption.
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And there's an asterisk here.
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But like basically oxygen consumption on Lee happens when plant material is burned, either in a fire or in an organism.
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Since oxygen is abundant to the atmosphere, carbon dioxide is the limiting agent in this carbon cycle, which is why there's such a tiny amount of see you two in the atmosphere that carbon dioxide is what gets trapped and brought to the bottom of the ocean.
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When these blooms happen there over geologic time, they're compressed from carbohydrates into hydrocarbons, fossil fuels.
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And when we burn those fossil fuels, yes, that consumes oxygen, and we can see the oxygen concentration of the earth going down.
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But it's not a big percentage of the total amount of oxygen in the atmosphere, because there's a lot.
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But the carbon dioxide concentration is extremely low, and we're well on our way to doubling it.
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And that's one of the very real reasons why it's a bad idea to burn rainforest.
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The Amazon rain forest is a sink for something like 90 billion tons of carbon dioxide, and that is a huge service that we need.
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So we're not going to suffocate.
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Very happy about.
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That sounds miserable, but I kind of wish we could see the threats to the other Service is that the Earth provides to us as similarly significant because they are.
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John, I'll see you on Tuesday.
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We're gonna be okay.
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All right?
