Controversies in the Earth Sciences

Penn State Research


Sridhar Anandakrishnan, a professor in Penn State's Department of Geosciences, conducts field geophysical experiments on glaciers in Antarctica. Watch the video below to find out more about how his work on glacier dynamics relates to other studies of recent climate change.

Video: A Visit to Antarctica with Dr. Anandakrishnan - Part 1 (05:06)

A Visit to Antarctica with Dr. Anandakrishnan - Part 1
Click here for a transcript of the A Visit to Antarctica with Dr. Anandakrishnan - Part 1

[MUSIC PLAYING] SRIDHAR ANANDAKRISHNAN: Hi my name's Sridhar Anandakrishnan. I'm an associate professor of geosciences at Penn State University. 

I'm going to give you a short bio, a little bit of background about myself. I first went to Antarctica-- gosh-- almost 30 years ago in 1985. It was the first time I went down. I went down just as a worker on a project with some other folks that were studying these glaciers. 

I just went there to look around and to help out on the project. I was captivated by the, really, the stark and uncompromising beauty of the continent. And I decided I want to study this. 

Over the years, I discovered that not only was it personally fulfilling because I was working in a beautiful place, but it was also important for the rest of the planet. What happens in Antarctica doesn't just stay in Antarctica. It actually comes out and affects the rest of us here. And I've enjoyed very much being a part of that-- that search. 


What got me most interested in glacial climate change was originally simply I wanted to be in Antarctica. And one of the most important things about Antarctica is how it's going to change in the future as we continue to pump carbon dioxide, CO2 into the atmosphere, as the temperature starts to increase-- continues to increase, what does it do to the ice of Antarctica? 

That's what originally got me interested in it. But since then, one of the things that sustains my interest is what's going to happen to people who depend on water from glaciers, fresh water from glaciers-- people in the Mountain West of this country, people in the Andes, and most importantly to me, people in India and Bangladesh and Pakistan, who depend on meltwater from glaciers in Himalayan mountain range. 

And as temperatures increase, those glaciers are melting and being lost at an increasingly rapid pace. And so the future looks very bleak for those people. We need to understand this. 

So when I'm in Antarctica, our days are divided, really, into three parts. One part is simply surviving, living-- waking up in the morning, making breakfast, feeding ourselves and making communications. 

We've got to call folks back home and let them know we're OK. If they don't hear from us for a day or two days, then they'll send out a rescue airplane. Because we're in such a remote place, we have to keep very close touch with our base station. 

It's just four of us out there in the middle of the glacier and not another person for maybe 500 miles in any direction and just four of us in our tents and our gear. So the first thing that we do out there is just make sure we're safe, make sure that we're happy, healthy, things are going OK. 

The second thing that we do out there is do our work-- wake up in the morning. We've taking care of ourselves. The next thing is we have to go out and do the work that the National Science Foundation is paying us to do, that Penn State University is paying me to do and that I love to do. 

And that research is you try and understand how thick the glacier is and what's underneath the glacier when I walk around on top of any landmass a glacier or even the rocks of central Pennsylvania, all you see is the surface. What's down below, what's down a mile underneath us? 

You don't really know unless you can do the experiments that I do, which are called seismic reflection imaging where we set off a small explosive shot at the surface. And the sound waves from that go down through the glacier, hit the bottom, bounce off it, come back up to the surface. 

And then we measure how long did it take, how much energy did it leave going down and coming back-- those sorts of things tell us a lot about the glacier. So that's the work we do. So wake up in the morning and spend the whole day setting off explosive shots, a pyromaniac's dream come true. 

But we do it safely. We do it carefully. We don't do it in a wasteful way. And we are doing it to find out more about the glacier. 

And then we'll do that all day long until the evening. And then once again we have to make sure we're safe, make sure we're healthy. 

The third thing we do is try and keep the excitement of being out there, that energy up through a long, six-week, eight-week, 10-week season. You have to make sure you're having fun. Make sure that everybody's spirits are up. And it's an incredibly important part of the day to come together as a community, even though a very small community-- four of us-- and make sure everybody's OK. 


Video: A Visit to Antarctica with Dr. Anandakrishnan - Part 2 (5:07)

A Visit to Antarctica with Dr. Anandakrishnan - Part 2
Click here for a transcript of A Visit to Antarctica with Dr. Anandakrishnan - Part 2

[MUSIC PLAYING] DR. SRIDHAR ANANDAKRISHNAN: So some of the things that are really good about this job are I get to do fun things in beautiful places. But that's a very personal reward. It's almost a selfish reward. Really, one of the most extraordinary, positive aspects of this work is what's happening in Antarctica affects us over here in central Pennsylvania. 

Sea levels are rising. Glaciers are melting. Temperatures are rising. Sea ice is melting. All these things affect us here in the US, and I have a piece of that. I'm working on that. I'm studying that. I'm learning about it. And boy, is that ever an exciting and deeply fulfilling part of the job. So that's the positive part. 

And the downside of it is I'm gone from home a long time. I'll leave here sort of mid-November. You have to remember, in Antarctica, the seasons are reversed. And so it's summertime down there in November, December, and January. And so I go down there when it's, quote, "summer," even though it's still cold. You can see the snowmobiles whipping by behind me. 

And I'm away from home for 10 weeks at a time. And that's pretty hard on my family. But nevertheless, we manage. I've been doing this for a number of years. So those are the-- you have to always balance these things. 


If there's one cliche that people know about glaciers is, oh, it's moving at a glacial pace. You get behind your grandmother driving a Buick LTD and you say, oh, she's moving at a glacial pace. One of the extraordinary things that I have discovered that nobody expected-- I didn't expect, anybody else expected-- is that these glaciers are astonishingly dynamic. They change the speed at which they flow from their standard glacial pace to what are, for glaciers, extraordinarily fast rates over very short periods of time. 

So let me give you an example. Most glaciers flow maybe two or three feet in a day, and that's a booking case for glaciers. Most glaciers, 90% of the glaciers, will flow maybe a few inches per day. But the really fast ones might make it to two or three feet in a day. 

Well, there's one glacier in particular in Antarctica that I've worked on a lot called William's Ice Stream that goes the whole range. Part of the day, it goes at zero to one inch per day, just hardly moving at all, just sitting there stuck. And then, for very short periods of that day, it'll suddenly lurch forward. It'll speed up to 5 or 10 or 15 feet per day. The speed at which it's going will suddenly just whip forward. 

Now, 15 feet per day might not sound like a lot to you. You could probably do 15 feet in just a few seconds with just walking along. But for a glacier to speed up from nothing to very, very fast for a glacier and then back to nothing in a day is an astonishing phenomenon, and one that nobody really expected. And I'm really quite proud to have been a part of that discovery. 

Let me tell you a little bit about what comes next. We've spent a lot of time studying the continent. We've learned some of these extraordinary things that we didn't know-- what I referred to a little while ago about how the glaciers can change their speed at rates that we hadn't understood. It's those sorts of unanticipated, unexpected behavior modes of the glacier that we really need to nail down in the coming years. 

So when scientists go out and study a system, they like to build computer models of how that system is operating now and how it's going to operate in the future so that we can dial in different parameters. We can say, OK, the temperature's going to go up by two degrees. What'll happen to Antarctica? It'll go up by three degrees. What'll happen to Antarctica? 

Well, for us to believe those projections, believe those prognostications, those models need to be good models. And we're finding out that these glaciers are changing so rapidly that our models aren't as good as we thought. And that's what we're going to have to work on next.