Dr. Lesley Ott SME Transcript

Narration: Dr. Lesley Ott

Transcript:

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The Earth is

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the most

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important planet that we study,

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at least in my opinion.

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And the work that we do from space

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is incredibly valuable

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in giving that this global vantage point,

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the ability to see everything,

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It's like going to the world,

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you know, the top of a big hill

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and you get to look down

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and see everything,

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but there's no place we can do that.

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What we're actually

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on the surface of the earth.

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And so the work that NASA does

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in exploring space

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and finding new ways

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to get instruments

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that look back at Earth

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have given us this

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incredibly rich dataset

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that help us understand

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the world

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and how it's changing over

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the course of multiple decades now

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you know, when NASA's first started

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sending people up into space,

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they would look down at the Earth

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and they would see things

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that we see from the ground.

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But this whole different

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perspective, right?

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They could see the movement

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of these big clouds and weather systems.

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They could see lights at night. Right.

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And so over time,

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that guided

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the development of instruments

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that we've sent into space

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that look back at our planet,

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that are able to monitor

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weather systems,

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that are able to monitor human activity.

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So now those data sets have provided

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this foundation of understand

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how the Earth functions as a planet

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over the course of the

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past several decades.

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Studying the Earth as a

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system is incredibly important

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because the more we look

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at individual variables

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like rainfall or air

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pollutants or temperature,

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we realize how interconnected

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the Earth is as a planet, as a system,

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right when we warm the planet,

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when we increase temperatures,

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we don't just get warmth

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and balmy days, right?

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We get changes in weather systems.

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We get changes

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in the acuteness of pollution episodes

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that send people to the hospital.

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We change the frequency

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and the patterns of wildfires

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so understanding

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all those different variables

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and how connected they are,

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that's one of the most special things

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that we get

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from this record of Earth observations

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and this really impressive

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global perspective

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that NASA's satellites give us

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as Earth scientists

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It's incredibly important for us to study

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how the planet's changing.

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Our observations helped us understand

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how the planet functions.

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But we also know we want to know

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how that's going to evolve

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in coming decades, coming centuries.

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So really understanding the climate

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that we have today

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and how that's changing, that's

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providing this really important

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benchmark to understand

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how extremes might be changing

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and also to understand how the efforts

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that we're all taking to mitigate

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climate change

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are having a positive effect

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both now and in the future.

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So atmospheric chemistry is a

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lot like the chemistry

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that you probably learned

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about in high school.

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But when we talk about

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atmospheric chemistry,

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we're talking about the way

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that that molecules in the form of gases

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react with each other

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to form new molecules,

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many of them

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in very small concentrations.

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But those can be incredibly important

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and affecting things like air quality

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pollution and public health

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and the evolution of climate change

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setting.

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Atmospheric chemistry

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is really, really important for us

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in order to be able to understand

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and predict

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things like air pollution

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episodes, the concentrations

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of greenhouse gases,

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the rates at which

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some of these reactions

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occur are driven by the concentrations

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of different gases in the atmosphere.

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But they can also be affected

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by things like changes in humidity,

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changes in temperature.

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So when we study atmospheric chemistry,

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we're not just looking at

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how are those processes occurring now,

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but how are those going to change

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with climate change.

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How sensitive

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are some of those types of reactions

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to a world that's getting warmer and in

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a lot of cases more moist?

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So greenhouse gases are this

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really important type of gas

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that's present in the atmosphere

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in really, really small concentrations.

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But it's important

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because they're very,

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very efficient

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at trapping

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long wave heat

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that's emitted from the Earth's surface.

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And they can do this

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because greenhouse gases

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are comprised of more than two atoms.

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That means structurally

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they have a little bit

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more ability to move

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and they can absorb that energy

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through rotational

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translational vibrational motion.

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So some of the most important

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greenhouse gases

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that are influenced by

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human activities are carbon

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dioxide or CO2,

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as you may have heard of, called methane,

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nitrous oxide or N2O

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and also water vapor.

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Now, water vapor obviously occurs

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naturally in the atmosphere.

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That's important for

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for sustaining life

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sustaining precipitation.

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But as the planet warms,

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the concentration of water

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vapor can increase.

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So you have this positive feedback,

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as scientists call it, where water vapor

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is contributing to climate change,

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even though it's there

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naturally in the atmosphere.

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So methane is really powerful.

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Greenhouse gas

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is actually more powerful

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on a molecule by molecule

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basis than carbon dioxide,

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even though it's

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present in the atmosphere

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in much smaller concentrations.

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Now, methane is emitted

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by a number of both human

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and natural sources.

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So things like oil

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and natural gas production, landfills,

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wastewater treatment facilities, it's

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also emitted by natural sources

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like wetlands.

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About 30% of the budget is wetlands.

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By many estimates,

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that's really important

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because in some cases, it's harder

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for us to manage and control

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those diffuse natural sources.

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And another reason

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scientists are really concerned

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about what's happening

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with methane right now

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is that methane emissions from places

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like wetlands are temperature sensitive,

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meaning they can accelerate

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in a warming world.

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And we want to make sure we understand

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how wetlands are changing,

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how those human and natural components to

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methane emissions are changing as climate

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change progresses.

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So another reason that methane

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is really important right now

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is that

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policymakers are targeting

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methane emissions as a

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as a major effort to reduce

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emissions from methane in the near term.

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They hope that that buys us some time

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to bring down carbon

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dioxide concentrations in the future.

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So things like trying to reduce

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fugitive emissions from oil,

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natural gas is getting a lot of attention

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because the hope is that

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that can give us some time, both

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because methane is a very powerful gas

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and because there's a lot of agreement

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from both policymakers, industry

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and the general public

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that we have places

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to reduce those emissions

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that'll make life a little bit safer

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and help us reduce

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climate change at the same time.

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So greenhouse gases are really effective

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at trapping heat.

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We know that.

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And most of the warming

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is due to CO2 or carbon dioxide,

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which is built up in the atmosphere

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over the past hundred 50 years.

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And so that's the main driver

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trapping heat

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in the Earth's system

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and causing a lot of the changes

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we associate with climate change.

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So the 1880s is important

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in terms of general dates.

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The technology

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to measure temperature pressure, rainfall

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was being distributed

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in communicated more broadly.

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And so that's one of those

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early dates in history

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where scientists were able to gather

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enough information

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to have a reliable picture

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of global temperature

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in a global sense

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to understand how things are changing.

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So trace

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gases are really important

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in raising global temperatures.

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Most of the atmosphere

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is into and out to atoms,

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and they don't have a lot of flexibility

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to absorb energy. Right.

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But when you have these

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special greenhouse gases

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that have at least three atoms,

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they have more capacity

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to absorb energy and absorb

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that in the molecular bonds

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between those atoms.

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That means that

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even though they're present

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in the atmosphere,

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only in very,

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very small concentrations,

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they have this outsized impact

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on the temperature budget

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in being able

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to very efficiently

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trap energy that's emitted

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back to space from the Earth's surface.

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So the way that heat is

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expressed throughout the planet

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when it's trapped by

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these greenhouse gases

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is is really diverse. Right,

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We see all of these different impacts

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for example,

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we see changes in ocean temperatures

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that can affect ocean biology.

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It also affects ocean currents,

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the presence of ice

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at the high and low latitudes.

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But we also see changes on land.

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We see changes in ecosystems,

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changes in growing

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season, changes in the frequency

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and severity of droughts

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that can affect the risk of fires.

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We see changes in life.

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We see changes in the migration

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patterns of birds and fish.

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And so these are some of the ways

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that the planet is interconnected.

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And when we trap heat,

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that's not just

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expressing itself

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as this change

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in the daily temperature value,

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it's expressing itself

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in all of these fundamental ways

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that our lives

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are influenced day after day.

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This is something

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people ask a lot, right?

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And early

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on, people use to focus on

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global warming, global warming.

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And I think as scientists,

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we say climate change more frequently

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because global warming

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is really only talking

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about one part of the problem,

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the fact that greenhouse gases trap heat,

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and that's expressed

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in global temperature increases.

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When we talk about climate change,

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we're talking about these really complex

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interactive effects, things

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like changes in vegetation

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changes and fires, changes in air

00:10:50:14 - 00:10:52:16

pollution, ocean circulation,

00:10:52:16 - 00:10:54:13

really something as fundamental

00:10:54:13 - 00:10:56:10

as temperature can't change in a vacuum

00:10:56:10 - 00:10:57:07

without affecting

00:10:57:07 - 00:10:58:21

literally every aspect

00:10:58:21 - 00:11:00:12

of the earth as a planet.

00:11:00:12 - 00:11:01:21

And so that's why we like to call it

00:11:01:21 - 00:11:02:16

climate change,

00:11:02:16 - 00:11:03:11

to just make sure

00:11:03:11 - 00:11:04:10

we're encompassing

00:11:04:10 - 00:11:05:18

the full range of effects

00:11:05:18 - 00:11:07:19

that are happening across the planet.

00:11:15:00 - 00:11:17:19

So scientists, policymakers and citizens

00:11:17:19 - 00:11:18:05

all across

00:11:18:05 - 00:11:18:20

the world are working

00:11:18:20 - 00:11:19:08

really hard

00:11:19:08 - 00:11:21:08

to get us to net zero emissions,

00:11:21:08 - 00:11:23:00

to bring us down to a point where

00:11:23:00 - 00:11:25:05

we're not emitting a net amount of carbon

00:11:25:05 - 00:11:25:18

that that

00:11:25:18 - 00:11:29:08

the emissions are balanced by by natural

00:11:29:10 - 00:11:31:01

and imposed things. Right.

00:11:31:01 - 00:11:31:10

But one thing

00:11:31:10 - 00:11:32:02

that's really important

00:11:32:02 - 00:11:33:11

for people to know is, one, it's

00:11:33:11 - 00:11:34:18

going to take us some time to get there.

00:11:34:18 - 00:11:36:02

That's not going to happen overnight.

00:11:36:02 - 00:11:37:05

It's going to happen

00:11:37:05 - 00:11:38:19

over the course of decades.

00:11:38:19 - 00:11:41:11

And even when we get to net zero,

00:11:41:11 - 00:11:42:10

that doesn't mean

00:11:42:10 - 00:11:43:09

that carbon dioxide

00:11:43:09 - 00:11:44:20

concentrations, greenhouse

00:11:44:20 - 00:11:46:04

gas concentrations

00:11:46:04 - 00:11:46:16

fall back

00:11:46:16 - 00:11:48:15

to pre-industrial levels overnight.

00:11:48:15 - 00:11:50:10

We've been emitting these things

00:11:50:10 - 00:11:52:13

for well over a hundred years.

00:11:52:13 - 00:11:54:12

We've been perturbing these cycles

00:11:54:12 - 00:11:55:17

and it's going to take time.

00:11:55:17 - 00:11:58:18

We expect over the course of decades

00:11:59:00 - 00:12:00:09

to even over a century,

00:12:00:09 - 00:12:03:09

to see those decreases in greenhouse

00:12:03:09 - 00:12:04:20

gas concentrations

00:12:04:20 - 00:12:08:05

continue as carbon is absorbed

00:12:08:07 - 00:12:09:18

into natural reservoirs.

00:12:09:18 - 00:12:11:17

And you see more of that balance return.

00:12:11:17 - 00:12:12:14

So that's one thing

00:12:12:14 - 00:12:14:04

that is important for people to note.

00:12:14:04 - 00:12:15:23

Net zero doesn't mean an immediate

00:12:15:23 - 00:12:18:05

end to global climate change.

00:12:25:03 - 00:12:26:23

So scientists look at a

00:12:26:23 - 00:12:28:08

range of explanations for everything.

00:12:28:08 - 00:12:29:10

It's important for people to think

00:12:29:10 - 00:12:31:04

we don't just jump to conclusions.

00:12:31:04 - 00:12:33:04

So we look at all of these explanations

00:12:33:04 - 00:12:33:19

to understand

00:12:33:19 - 00:12:35:15

what are the drivers of climate change,

00:12:35:15 - 00:12:36:11

things like changes

00:12:36:11 - 00:12:37:12

in the solar radiation

00:12:37:12 - 00:12:39:18

cycles, volcanoes that

00:12:39:18 - 00:12:41:06

that erupt and change

00:12:41:06 - 00:12:43:04

atmospheric composition naturally.

00:12:43:04 - 00:12:45:07

And when we do computer simulations,

00:12:45:07 - 00:12:46:23

none of these things can explain

00:12:46:23 - 00:12:48:07

the dramatic changes

00:12:48:07 - 00:12:49:22

that we're seeing in global temperature,

00:12:49:22 - 00:12:51:07

which occur at the same time

00:12:51:07 - 00:12:52:16

as greenhouse gases.

00:12:52:16 - 00:12:54:11

Really only the system makes sense

00:12:54:11 - 00:12:55:06

with the warming

00:12:55:06 - 00:12:56:05

that we know happens

00:12:56:05 - 00:12:58:14

as a result of greenhouse gases.

00:12:58:14 - 00:13:00:22

In addition, people should know that

00:13:00:22 - 00:13:03:21

the imprint of climate change from humans

00:13:04:02 - 00:13:06:14

has a really distinct signature

00:13:06:14 - 00:13:08:08

in terms of temperature.

00:13:08:08 - 00:13:09:16

When you have this warming

00:13:09:16 - 00:13:11:20

for greenhouse gases that traps heat

00:13:11:20 - 00:13:13:03

throughout the atmosphere,

00:13:13:03 - 00:13:14:01

it acts as a blanket

00:13:14:01 - 00:13:15:06

that warms the surface,

00:13:15:06 - 00:13:16:21

but it makes the top of the atmosphere

00:13:16:21 - 00:13:18:03

a little bit colder.

00:13:18:03 - 00:13:19:06

And we can actually see

00:13:19:06 - 00:13:20:19

in the records of observations

00:13:20:19 - 00:13:21:20

that we have

00:13:21:20 - 00:13:23:08

that this fingerprint, this unique

00:13:23:08 - 00:13:24:08

trapping of heat

00:13:24:08 - 00:13:25:16

from greenhouse gases

00:13:25:16 - 00:13:27:01

is occurring at the same time

00:13:27:01 - 00:13:28:07

temperatures are warming.

00:13:28:07 - 00:13:29:22

So that's a really dead giveaway

00:13:29:22 - 00:13:31:16

that this isn't some natural cycle.

00:13:31:16 - 00:13:32:23

This is warming

00:13:32:23 - 00:13:34:05

that's caused by absorption

00:13:34:05 - 00:13:36:11

from greenhouse gases.

00:13:43:04 - 00:13:44:08

So we talk about models.

00:13:44:08 - 00:13:45:10

You probably hear about this a lot.

00:13:45:10 - 00:13:48:02

Models are really just a set of equations

00:13:48:02 - 00:13:49:04

that describe

00:13:49:04 - 00:13:50:17

our best understanding

00:13:50:17 - 00:13:52:21

of the way some system functions.

00:13:52:21 - 00:13:54:07

It can be a lot of equations.

00:13:54:07 - 00:13:56:07

They can be very long and complicated.

00:13:56:07 - 00:13:57:22

They can be solved by supercomputers

00:13:57:22 - 00:13:58:12

and on a grid,

00:13:58:12 - 00:13:59:18

which is actually how

00:13:59:18 - 00:14:01:12

weather and climate models work.

00:14:01:12 - 00:14:02:12

But at the end of the day,

00:14:02:12 - 00:14:04:01

they're really just our best

00:14:04:01 - 00:14:05:14

understanding, encapsulated

00:14:05:14 - 00:14:07:03

in a mathematical form

00:14:07:03 - 00:14:08:05

that help us

00:14:08:05 - 00:14:11:00

integrate and predict into the future.

00:14:18:02 - 00:14:19:10

So the weather and climate models

00:14:19:10 - 00:14:20:04

that we use

00:14:20:04 - 00:14:22:03

to study things like climate change

00:14:22:03 - 00:14:24:08

are made up of these sets of equations.

00:14:24:08 - 00:14:27:00

They're being solved on supercomputers.

00:14:27:00 - 00:14:27:11

But one thing

00:14:27:11 - 00:14:28:11

that's really important to know

00:14:28:11 - 00:14:29:17

is that we don't just make up

00:14:29:17 - 00:14:30:17

these equations, right?

00:14:30:17 - 00:14:31:23

We develop equations

00:14:31:23 - 00:14:33:16

and we refined them over time

00:14:33:16 - 00:14:35:09

using a combination

00:14:35:09 - 00:14:38:03

of satellite data, of ground based data.

00:14:38:03 - 00:14:40:04

So that helps us make and test

00:14:40:04 - 00:14:42:15

the best equations over time.

00:14:42:15 - 00:14:44:04

We're also continually

00:14:44:04 - 00:14:45:13

evaluating those models

00:14:45:13 - 00:14:47:06

with a combination of data to ensure

00:14:47:06 - 00:14:48:23

we know what they do well,

00:14:48:23 - 00:14:51:07

where they can use improvement.

00:14:51:07 - 00:14:54:17

We also use data sets to initialize

00:14:54:17 - 00:14:55:18

predictions, right?

00:14:55:18 - 00:14:57:12

So when we make a weather forecast

00:14:57:12 - 00:14:58:18

that's actually taking data

00:14:58:18 - 00:14:59:14

from satellites,

00:14:59:14 - 00:15:00:00

from ground

00:15:00:00 - 00:15:00:14

based networks,

00:15:00:14 - 00:15:01:20

even from from airplanes,

00:15:01:20 - 00:15:02:14

passenger airplanes

00:15:02:14 - 00:15:04:02

that people fly on every day

00:15:04:02 - 00:15:05:04

and using that

00:15:05:04 - 00:15:06:14

to give us a reliable picture

00:15:06:14 - 00:15:07:10

of what's happening

00:15:07:10 - 00:15:09:01

with today's conditions

00:15:09:01 - 00:15:10:20

so we can make a reliable prediction

00:15:10:20 - 00:15:11:17

into the future

00:15:11:17 - 00:15:13:20

to inform people all over the world

00:15:13:20 - 00:15:15:12

how weather is changing.

00:15:15:12 - 00:15:16:09

And we do the same thing

00:15:16:09 - 00:15:17:11

for seasonal predictions.

00:15:17:11 - 00:15:18:20

So we can predict things

00:15:18:20 - 00:15:20:03

nine months into the future

00:15:20:03 - 00:15:21:12

and give people some sense

00:15:21:12 - 00:15:23:12

of how seasonal temperatures

00:15:23:12 - 00:15:25:16

might evolve.

00:15:32:12 - 00:15:33:16

So one thing that's really

00:15:33:16 - 00:15:34:16

exciting about models

00:15:34:16 - 00:15:36:13

is the whole landscape of models

00:15:36:13 - 00:15:38:23

has changed, both with the availability

00:15:38:23 - 00:15:39:16

of high performance

00:15:39:16 - 00:15:41:06

computing supercomputers

00:15:41:06 - 00:15:43:10

and the availability of satellite data.

00:15:43:10 - 00:15:44:06

So some of the things

00:15:44:06 - 00:15:45:19

that we're able to do with models

00:15:45:19 - 00:15:47:00

we couldn't do five

00:15:47:00 - 00:15:48:17

even ten years ago,

00:15:48:17 - 00:15:50:10

things like running models

00:15:50:10 - 00:15:51:09

and much finer

00:15:51:09 - 00:15:53:03

spatial scales to understand

00:15:53:03 - 00:15:53:22

how conditions

00:15:53:22 - 00:15:56:06

are changing in local areas, urban areas,

00:15:56:06 - 00:15:57:19

even within neighborhoods.

00:15:57:19 - 00:15:59:05

The other thing that's really changing

00:15:59:05 - 00:16:00:22

is the complexity of processes

00:16:00:22 - 00:16:01:15

and models.

00:16:01:15 - 00:16:02:22

Used to be that we had one model

00:16:02:22 - 00:16:04:00

that would tell us about weather,

00:16:04:00 - 00:16:05:04

and then we had to take that data,

00:16:05:04 - 00:16:06:11

plug it into a separate model

00:16:06:11 - 00:16:08:00

that would tell us about greenhouse gases

00:16:08:00 - 00:16:09:05

and air quality.

00:16:09:05 - 00:16:10:12

Today's models include

00:16:10:12 - 00:16:12:23

all of those processes at the same time.

00:16:12:23 - 00:16:13:17

That's important

00:16:13:17 - 00:16:15:11

for having the most accuracy

00:16:15:11 - 00:16:16:01

and being able

00:16:16:01 - 00:16:17:02

to provide the best

00:16:17:02 - 00:16:18:15

and most integrated information

00:16:18:15 - 00:16:20:02

that helps policymakers

00:16:20:02 - 00:16:22:10

navigate a number of climate

00:16:22:10 - 00:16:25:00

related challenges all at once.

00:16:31:17 - 00:16:33:01

So models are an incredibly

00:16:33:01 - 00:16:34:02

important component

00:16:34:02 - 00:16:37:02

of helping us understand and navigate

00:16:37:07 - 00:16:38:07

a warming climate.

00:16:38:07 - 00:16:39:16

But I want people to understand that

00:16:39:16 - 00:16:40:15

when we talk about temperature

00:16:40:15 - 00:16:42:22

change, global temperature

00:16:42:22 - 00:16:45:00

changes over the past 250 years,

00:16:45:00 - 00:16:47:00

that knowledge is grounded

00:16:47:00 - 00:16:49:18

in observations taking at ground stations

00:16:49:18 - 00:16:51:10

across the world, in some cases

00:16:51:10 - 00:16:53:07

satellite data as well.

00:16:53:07 - 00:16:54:18

But really

00:16:54:18 - 00:16:55:15

the observations

00:16:55:15 - 00:16:57:06

are the basis of understanding

00:16:57:06 - 00:16:57:22

and documenting

00:16:57:22 - 00:16:59:09

how the planet has changed.

00:16:59:09 - 00:17:00:16

Now, using those observations,

00:17:00:16 - 00:17:02:06

we create better models.

00:17:02:06 - 00:17:03:20

Those models can help us understand

00:17:03:20 - 00:17:05:17

things that we can't observe directly,

00:17:05:17 - 00:17:07:08

like why the climate is changing,

00:17:07:08 - 00:17:08:01

what are the relative

00:17:08:01 - 00:17:10:06

contributions of natural factors

00:17:10:06 - 00:17:11:10

and human factors.

00:17:11:10 - 00:17:12:19

And really importantly,

00:17:12:19 - 00:17:14:06

given an amount of warming,

00:17:14:06 - 00:17:15:20

how is that going to change

00:17:15:20 - 00:17:17:06

the trajectory of the planet in

00:17:17:06 - 00:17:19:15

coming decades and centuries?

00:17:26:11 - 00:17:27:07

know, it's really tricky.

00:17:27:07 - 00:17:28:10

We have computer models

00:17:28:10 - 00:17:29:20

and in a lot of cases

00:17:29:20 - 00:17:31:15

we know a lot more in terms of science

00:17:31:15 - 00:17:32:12

and we can actually write

00:17:32:12 - 00:17:34:05

and solve in terms of these equations

00:17:34:05 - 00:17:36:07

because it's a lot of compute power,

00:17:36:07 - 00:17:38:17

a lot of energy to make those models go.

00:17:38:17 - 00:17:40:00

Some of the things that we know

00:17:40:00 - 00:17:41:00

we want to understand

00:17:41:00 - 00:17:42:08

and increase the complexity

00:17:42:08 - 00:17:43:14

of in these projection

00:17:43:14 - 00:17:44:08

models

00:17:44:08 - 00:17:46:01

are the interactions between

00:17:46:01 - 00:17:46:22

tiny particles

00:17:46:22 - 00:17:48:00

called aerosols

00:17:48:00 - 00:17:48:20

and clouds,

00:17:48:20 - 00:17:50:15

because those are really important

00:17:50:15 - 00:17:52:01

in changing

00:17:52:01 - 00:17:54:09

how clouds either

00:17:54:09 - 00:17:56:13

trap or reflect radiation.

00:17:56:13 - 00:17:57:22

So it really affects the way

00:17:57:22 - 00:17:59:05

that climate change

00:17:59:05 - 00:18:00:19

progresses, also affects things

00:18:00:19 - 00:18:02:18

like the formation of storms.

00:18:02:18 - 00:18:03:16

Another area

00:18:03:16 - 00:18:04:15

where we would like to have

00:18:04:15 - 00:18:06:01

a lot more information

00:18:06:01 - 00:18:07:00

is the way

00:18:07:00 - 00:18:10:12

that the natural sinks of carbon

00:18:10:12 - 00:18:11:19

dioxide on the land in

00:18:11:19 - 00:18:14:08

the ocean are affected by climate change.

00:18:14:08 - 00:18:15:19

So right now,

00:18:15:19 - 00:18:17:17

trees and the world's oceans

00:18:17:17 - 00:18:18:15

absorb about half

00:18:18:15 - 00:18:20:21

of our pollution of carbon dioxide,

00:18:20:21 - 00:18:22:14

and it's giving us a huge assist

00:18:22:14 - 00:18:23:23

in terms of climate change.

00:18:23:23 - 00:18:24:18

But one of the things

00:18:24:18 - 00:18:26:04

that's a big source of uncertainty

00:18:26:04 - 00:18:28:00

is how long that can continue

00:18:28:00 - 00:18:29:17

and how are things like fires

00:18:29:17 - 00:18:30:22

and droughts and more stress

00:18:30:22 - 00:18:31:21

on vegetation

00:18:31:21 - 00:18:34:00

influencing that ability to absorb

00:18:34:00 - 00:18:36:23

and help us out with climate change.

00:18:44:05 - 00:18:45:02

So one thing that's really

00:18:45:02 - 00:18:46:10

important for people to understand

00:18:46:10 - 00:18:47:11

when we talk about

00:18:47:11 - 00:18:49:04

global temperature rise

00:18:49:04 - 00:18:51:04

is that we're talking about the increase

00:18:51:04 - 00:18:52:18

in global mean temperature,

00:18:52:18 - 00:18:53:20

but that doesn't mean you're

00:18:53:20 - 00:18:55:01

not going to have an extreme winter.

00:18:55:01 - 00:18:55:13

It doesn't mean

00:18:55:13 - 00:18:58:04

you might not have a big snowstorm

00:18:58:04 - 00:18:59:17

in your area. Right.

00:18:59:17 - 00:19:01:00

Because that means that temperatures

00:19:01:00 - 00:19:02:00

across the world

00:19:02:00 - 00:19:03:06

as an aggregate

00:19:03:06 - 00:19:04:02

are getting warmer

00:19:04:02 - 00:19:05:15

and marching steadily upwards.

00:19:05:15 - 00:19:06:16

But still,

00:19:06:16 - 00:19:08:02

there's natural variability

00:19:08:02 - 00:19:10:04

from year to year, season to season.

00:19:10:04 - 00:19:11:12

There's spatial variability

00:19:11:12 - 00:19:12:00

with warming,

00:19:12:00 - 00:19:13:12

concentrating in some areas

00:19:13:12 - 00:19:15:02

like the higher latitudes

00:19:15:02 - 00:19:16:01

of the northern hemisphere

00:19:16:01 - 00:19:16:14

that are warming

00:19:16:14 - 00:19:18:03

more rapidly than others.

00:19:18:03 - 00:19:19:14

So there's all this complexity

00:19:19:14 - 00:19:20:14

from different regions

00:19:20:14 - 00:19:21:09

that are experiencing

00:19:21:09 - 00:19:23:00

climate change in different ways.

00:19:23:00 - 00:19:26:12

And some people confuse that with

00:19:26:14 - 00:19:27:18

the idea that global

00:19:27:18 - 00:19:29:03

temperature isn't increasing.

00:19:29:03 - 00:19:30:01

So that's an important thing

00:19:30:01 - 00:19:31:11

for people to understand and relating

00:19:31:11 - 00:19:32:15

what might be happening

00:19:32:15 - 00:19:33:16

in your own environment

00:19:33:16 - 00:19:35:07

with what's happening to the planet

00:19:35:07 - 00:19:36:08

as a whole.

00:19:43:05 - 00:19:44:15

You know, when people ask questions

00:19:44:15 - 00:19:45:05

like this,

00:19:45:05 - 00:19:46:02

I think it's important

00:19:46:02 - 00:19:47:00

to understand

00:19:47:00 - 00:19:48:13

that everybody has individual answers

00:19:48:13 - 00:19:49:19

and everybody is experiencing

00:19:49:19 - 00:19:51:10

climate change from a different lens.

00:19:51:10 - 00:19:52:21

It's affected by where you live.

00:19:52:21 - 00:19:53:21

It's affected by

00:19:53:21 - 00:19:55:22

just the way that you tackle problems.

00:19:55:22 - 00:19:57:02

But for me,

00:19:57:02 - 00:19:58:14

I tend to look at the positives

00:19:58:14 - 00:19:59:20

and I see a lot of attention.

00:19:59:20 - 00:20:01:00

I see a lot of people

00:20:01:00 - 00:20:03:12

working hard and understanding

00:20:03:12 - 00:20:04:20

that climate change is serious

00:20:04:20 - 00:20:05:20

and that we have to do something

00:20:05:20 - 00:20:06:13

about it,

00:20:06:13 - 00:20:06:23

you know, 5

00:20:06:23 - 00:20:07:16

to 10 years ago

00:20:07:16 - 00:20:08:19

when I used to do interviews,

00:20:08:19 - 00:20:10:22

people would say, Is climate change real?

00:20:10:22 - 00:20:12:03

And I don't get that reaction

00:20:12:03 - 00:20:13:12

very much anymore.

00:20:13:12 - 00:20:15:07

I get the question, is it too late?

00:20:15:07 - 00:20:16:07

What can I do?

00:20:16:07 - 00:20:18:12

How do I team up with my neighbors

00:20:18:12 - 00:20:19:01

to help?

00:20:19:01 - 00:20:21:10

And so that gives me some hope

00:20:21:10 - 00:20:23:09

that people are taking this seriously.

00:20:23:09 - 00:20:24:22

I think we see evidence of that

00:20:24:22 - 00:20:25:22

in some of the

00:20:25:22 - 00:20:28:04

the emissions reduction measures

00:20:28:04 - 00:20:29:00

that are being imposed

00:20:29:00 - 00:20:29:23

across the world

00:20:29:23 - 00:20:32:03

and the actions that are being taken

00:20:32:03 - 00:20:33:11

not just at large

00:20:33:11 - 00:20:35:03

administrative countries scales,

00:20:35:03 - 00:20:37:05

but within communities within cities.

00:20:37:05 - 00:20:39:03

Some of the cities are around the world.

00:20:39:03 - 00:20:39:21

Are the leaders

00:20:39:21 - 00:20:41:22

in reducing greenhouse gases,

00:20:41:22 - 00:20:43:22

working to reduce them even more quickly

00:20:43:22 - 00:20:45:10

than the countries that they're parts of?

00:20:45:10 - 00:20:45:22

Right.

00:20:45:22 - 00:20:47:10

So you see these smaller

00:20:47:10 - 00:20:48:08

collective actions

00:20:48:08 - 00:20:49:01

that can add up

00:20:49:01 - 00:20:50:07

to a really big difference.

00:20:50:07 - 00:20:51:11

And those are some of the reasons

00:20:51:11 - 00:20:53:08

that even though yeah, we have to admit

00:20:53:08 - 00:20:54:20

that this is a serious problem

00:20:54:20 - 00:20:56:08

and we have to tackle it,

00:20:56:08 - 00:20:58:08

I am hopeful and I do see change.