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>>Interviewer: As we enter the dog days of summer in the United States,

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things are heating up even more farther north with melting Arctic sea

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ice. And here to join us from NASA's Goddard Space Flight Center in Greenbelt, 

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Maryland is Dr. Nathan Kurtz. Thanks for joining us. >>Nathan: Hi, thanks for

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having me. >>Interviewer: The Arctic is losing sea ice at a faster rate in recent years.

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How are things looking this year, and what are we seeing in the long-term trend?

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>>Nathan: Well throughout the summer, Arctic sea ice melts, and as the 

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ice becomes thinner, some of the ice is not able to stay around

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as long during the summer. So this year what we're seeing is, melting is

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reaching a minimum extent of ice. And it's looking to be about 

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the sixth to eighth lowest on the satellite record. So a slight rebound from

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the past year and 2012, where it was a record low, but

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in the long-term average what we've done, we've seen about a third of the ice

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cover is gone, about two thirds of the volume and about half the thickness

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has gone. So overall the long-term trend is that we're 

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losing ice. >>Interviewer: Why are we seeing these

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changes in the Arctic? >>Nathan: Well we're seeing these changes because the ice

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is becoming thinner. It's not able to survive so long throughout the summer,

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we're also seeing these changes due to rising global temperatures. So the Arctic 

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is increasing about two to three times the global average in terms of the 

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temperature. And what this is doing is this is melting the temperature, and ice

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is a great bright reflector, it reflects a lot of the Sun's energy. 

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Whereas the ocean is dark, it absorbs the energy. So as the ocean

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absorbs the energy because of the melting ice, it increases temperatures 

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and this further melts the ice. We see a continued feedback

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of increasing temperatures and loss of ice. 

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>>Interviewer: What is NASA doing to understand these changes?

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>>Nathan: NASA has a variety of satellites and aircraft which are used to study 

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these changes. Next week we're launching the 

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ARISE mission, which is meant to study the interaction of clouds and sea ice. 

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So the ARISE mission will be flying through both

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clouds and over sea ice taking measurements of both aspects. 

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And so clouds have an interesting impact on the climate. 

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They're very important regulators of the climate. So, 

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ARISE will study this. NASA is also launching ICESat-2 in about two years,

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which uses a laser to range to the surface. 

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And this allows us to get an idea of how thick the sea ice and also how 

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thick ice is on land, and how these are changing and give us a better perspective 

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about how ice is changing on the planet. >>Interviewer: How will these

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changes affect the United States? >>Nathan: Well, these 

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changes actually can have a large impact on the US. 

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In particular, what's being studied now is the connection between 

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the warming in the Arctic, loss of sea ice, and changes to the jet stream. 

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So the jet stream is being changed because we have this 

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more meandering cycle, it's these up and down bumps, these

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north and south bumps, they become larger, they become more extreme. 

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And this brings more extreme weather to different parts of the US. And 

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as the jet stream is changing, it's also

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becoming more stationary in points, bringing different weather to the US. 

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>>Interviewer: Where can we learn more? >>Nathan: You can go to 

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NASA.gov/EarthRightNow to learn more. You can learn more about the NASA missions

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that I talked about. You can see 

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or download NASA data, and you can also see some really amazing pictures and

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videos of our home planet. >>Interviewer: Dr. Nathan Kurtz, thank you very much

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for joining us. >>Nathan: Thank you.