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carbon is the basic building block of

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life and these unique atoms are found

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everywhere on earth carbon makes up the

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Earth's plants and animals and carbon is

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also stored in the ocean the atmosphere

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and the crust of the planet a carbon

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atom could spend millions of years

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moving through the earth and a complex

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cycle understanding the carbon cycle and

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how it is changing is key to

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understanding Earth's changing climate

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on land plants remove carbon from the

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atmosphere through photosynthesis

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animals eat plants and either breathe

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out carbon or it moves up the food chain

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when plants and animals die and decay

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they transfer carbons back to the soil

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moving offshore the ocean holds huge

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amounts of carbon about 50 times the

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amount we find in the atmosphere the

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ocean sometimes called a carbon sink

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meaning that it absorbs or takes up

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carbon from the atmosphere it takes up

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carbon through physical and biological

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processes at the ocean's surface carbon

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dioxide from the atmosphere dissolves

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into the water tiny marine plants called

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phytoplankton use this carbon dioxide

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for photosynthesis phytoplankton are the

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base of the marine food web after

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animals eat the plants they breathe out

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the carbon or pass it up the food chain

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sometimes phytoplankton die decompose

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and are recycled in the surface waters

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phytoplankton can also sink to the ocean

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floor

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carrying carbon as they descend over

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long timescales this process has made

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the ocean floor the largest reservoir of

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carbon on the planet most of the oceans

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nutrients are in cold deep water in a

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process called upwelling currents bring

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nutrients and carbon up to the surface

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carbon can then be released as a gas

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back into the atmosphere

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continuing the carbon cycle by cycling

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huge amounts of carbon the ocean helps

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regulate climate so when you think of

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climate you don't often think of the

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ocean climate you think of isn't going

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to be hotter this year is gonna be

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colder this year but the oceans are

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actually a great regulator a controller

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of the Earth's climate and they even are

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controlling how much carbon is in the

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atmosphere which can slow down how

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quickly climate change is occurring at

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the most basic level the balance between

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incoming sunlight and outgoing heat

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determines the Earth's climate

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greenhouse gases act like a blanket and

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trap heat in the atmosphere carbon

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dioxide is a greenhouse gas in the past

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two centuries humans have increased

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atmospheric carbon dioxide by more than

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30 percent by burning fossil fuels and

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cutting down forests the earth has not

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experienced carbon dioxide levels this

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high for the past several million years

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researchers are learning that future

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climate change will depend on carbon

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levels in the land in the atmosphere and

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in the sea and how these levels respond

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to human disturbance about one third of

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all human generated carbon emissions has

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dissolved in the ocean more than 80

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percent of Earth's added heat is now

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stored in the ocean in the future as the

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planet gets warmer the water is going to

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warm up and warm water can hold less

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carbon than cold water the other thing

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is on a warmer planet some of the

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currents are going to slow down and so

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we might not be forming as much of this

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cold deep water so we won't be able to

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transport carbon into the deep sea so on

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the whole the ocean is going to become

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less effective at removing carbon from

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the atmosphere

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throughout most of Earth's ocean the

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warmer water weaker circulation and new

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temperature gradients that result from

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climate change will impact marine life

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and ecosystems these changes affect the

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oceans ability to store carbon increased

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carbon dioxide in the atmosphere impacts

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marine life in other ways as the ocean

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absorbs more carbon dioxide it becomes

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more acidic and this can be a threat to

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some of the organisms that live inside

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the ocean as Earth's climate continues

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to change

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how will researchers monitor something

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as big as the ocean and something as

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complex as the carbon cycle NASA Earth

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observing satellites give scientists the

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big-picture view of our home planet

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varied satellites help researchers

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detect changes in ocean climate and

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ecology over time providing vital

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insight into the health of our home

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planet

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