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Every one of the instruments on here

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has had to be spec'd to work

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at phenomenal levels.

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So we're going to be flying in the background atmosphere.

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That usually means there's very little

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of whatever you're trying to measure.

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For something like CO2

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we need such high sensitivity -

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there's lots of CO2 there,

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so every tiny change in it makes a difference.

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For something like ozone,

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we're going to be looking at very small numbers

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in the background atmosphere.

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For something like NOx, NO and NO2,

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the numbers are the lowest, even today,

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the lowest that instrument has ever measured

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was earlier on in the flight today.

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So the instrument is a cavity enhanced system,

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so we take light from the laser

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and put it through a sampling cell.

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And then we look and see how much light disappears

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when we have a certain amount

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of any of the four gases that we measure.

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For a given amount of CO2

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that's in the atmosphere,

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a certain amount will be absorbed

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of the laser light

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and then we can tell from that

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how much CO2 there is.

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We do a lot of profiles over TCCON sites,

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which are sites that look up at the sun

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and give us a total column of CO2 and methane

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between that site and the sun.

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But we also fly underneath some of the satellites.

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So today we've been doing an underpass

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under the OCO-2 satellite,

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where they measure CO2 columns.

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So we'll be sending all of the CO2 profiles

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that we measure

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to the OCO2 team

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to help with the validation of their instrument.

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A project like ATom

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is ideally suited for that,

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so it just takes a little extra coordination

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to try and get the most out of that.

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Looking at the real time data

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does give us ideas about

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what we should be interested in

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when it comes to looking at the data.

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Because there is a huge amount of data

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that's going to be produced from ATom,

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so I think there'll be a lot

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of the wider science community

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who end up using this data set,

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and I can see it being invaluable

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to all the modeling community.

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From what I've heard from them,

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they are very excited about the whole project.

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