We're here with Dr. Tom Wagner, cryospheric scientist with NASA.
Dr. Wagner, Operation Ice Bridge has scientists flying over the Arctic
this spring. Why are the poles so important to Earth's health?
The poles are important for a few reasons. The most important is this: changes at the poles profoundly
affect the climate on the whole rest of the planet, and what people need to realize
the planet is one big interconnected system. As you lose ice from the poles,
you wind up with dark ocean water exposed, which absorbs sunlight
and it continues the heating up of the ocean that's already going on today.
Also, too, if you are interested in sea level rise around the planet, the poles are
where the majority of the ice is. And as that ice melts and goes into the ocean, it
raises sea level. And about half of the tenth of an inch a year sea
level rise we see now comes from polar ice.
Why do we study this with planes, and not satellites?
Planes and satellites are complementary tools for studying it. Satellites give us this bird's-eye reconnaissance view
of the whole plane and they are actually the things that we use to figure out that the ice was actually
melting and changing. What we're doing though, now, is we're following up with detailed
studies with aircraft. What we can do with planes, too, we can do
different things we can't do by satellites. One of the most important things
is we can use ice-penetrating radar to map not just the surfaces of the ice, but also
to map the bed that's underneath it. On top of that too, one of the most important
questions for us is how thick is the ice, and how is that thickness changing.
And for that we use LIDAR on the aircraft, and we do detailed studies of how
glaciers in Greenland flow and draw down and also how are changes in the thickness
of the Arctic sea ice occuring and how is that correlated with changes in the ocean.
Well the sea ice in the Arctic grows thicker and returns during the winter. How is the ice fairing this season?
Right. Well, what happens is every year the ice grows
out to about, maybe two times the size of the continental US
It used to be that that ice would melt back every year to about the size of the continental US,
now it's melting back to less than half the size of the US.
And so what we're trying - and on top of that, it's thinner now than it's
ever been. And this year it looks like we're heading towards another one of those record
lows. But what's important is this: we need to understand how
that ice is connected to the ocean and the atmosphere so we can do better projections on it.
And what we do with Ice Bridge is we do the detailed work that will allow us to do that.
Ice Bridge isn't just looking at sea ice, but glaciers, too. Why are they important to study?
Glaciers, which is ice that is up on land,
are really important for us to study because as that ice melts
or it flows into the sea, it raises sea level directly.
There are places in Greenland where the glaciers flow at up to
100 feet per day. They're already contributing
to sea level rise. What we're worried about is that those glaciers
could speed up in a warming world. And so what we're doing is we're going out
and mapping them with every tool that we can to get a better handle on these processes.
Each successive Ice Bridge campaign is broadened in scope. What's new this year?
We're doing a couple of new things this year.
First thing is, we're going to a bunch of important glaciers and ice caps in northern Canada.
Those are also really important contributors to sea level rise and they appear
to be undergoing really rapid change right now, we're losing a lot of ice from them.
The other things is, because of our altimetry measurements, literally LIDAR or lasers
in the plane that tells us how high the ice is, we've realized how important
those measurements are so we're sending a second aircraft this year that's going to do a lot of detailed
flight lines over Greenland.
Can you tell us a little bit more
about what's it like for this airborne campaign to be up there in the Arctic?
Yeah, well, first thing - there's a lot of long hours, because
what you do is you get up really really early in the morning and you report to the hangar
and you try to see if the weather is safe enough for you to fly that day. And if the weather's
fit to fly, you go and get into this airplane which is this astounding beast
filled with all kinds of the most fascinating scientific gear you can imagine
and then you get on a really noisy flight and you go fly for eight hours
over places like the sea ice or over the interior of the Greenland ice sheet.
You see some fantastic sights. You know, over the sea ice, if you're
lucky, you're going to see big cracks and things moving around. Maybe you'll get really
lucky and see some wildlife, see some seals or you know, things like whales and
polar bears. If you're flying over Greenland, you're going to see these coastal areas
where you've got these rivers of ice meeting the ocean and you're going to see rock that's
some of the oldest rocks on planet Earth, billions of years old.
And it's a lot of hard work, but for the scientists who do it, we really enjoy it.
Thanks Dr. Wagner, and good luck with this years mission.
Thank you.