Finding Out How Fast Greenland Is Melting

We know that with climate change the Arctic is warming about twice as fast as the rest of the world and our big concern is sea level rise. How fast is Greenland melting and therefore how fast are the oceans rising. Our project was focused on the last 40 to 50 years where human-caused climate change has really accelerated the rapid melting of the snow at the surface. We're going to Greenland to try and understand how fast is Greenland melting today. If we can understand how fast is melting today and the processes that are causing it to melt today we can improve our models of how Greenland is going to melt in the future. Anytime we're looking to the future we have to be using our computer models and I know computer models get a lot of sort of bad flak from the public. People don't trust models. You can make models do anything but we don't. We don't want the model to do anything.

We want the models to predict what is likely to happen in the future. What we're trying to do is make those models as good as possible by showing that the models work and if they can reproduce what's happening today we have a lot more confidence that they're going to do a good job predicting the future. So what we wanted to do was actually physically go to Greenland, boots-on-the-ground, make these measurements that you can only make by being there. We were snowmobiling from the southwest part of Greenland a place called The Raven camp all the way up to the top of Greenland, the very top of the dome of the ice sheet at a place called summit and I was a total of around 1,200 kilometers that we had to snowmobile. We spend an enormous amount of time planning our logistics, training, making sure that our students have the mountaineering training, the wilderness first responder training, any other sort of scientific training that they need so that when we're in the field we stack the deck in our favor for being successful scientifically and for being completely safe.

At first I would say our whole team was pretty nervous about going out there when the plane drops you off your miles from the closest person, closest hospital the closest computer, There's no internet or cell phone service out there. Retrieving an ice core from Greenland and bringing it back to Dartmouth College in New Hampshire is actually quite an extensive process. You have to go you have to dig a pit about five feet deep and big enough to work inside this pit and this keeps you out of the wind and it also lets you get down to a layer that's a little bit harder in order to stand on and work from We start by hand turning the drill as we get the first meter to two meters of snow. After we send the barrel down into the hole we pull it back up with the ice core inside of it. We take off the top of it and shove the ice core out into a clean bin that holds the ice core. Once we have the ice core on the surface we can weigh it, we can measure it, we can take photographs of the ice core both with regular cameras and near infrared cameras and then we write down exactly where this ice core is from and we put it in a big plastic bag that we label since all the ice cores and all the snow look the same and we put it inside of a big box that will later ship back to New Hampshire My name is Karina Graeter.

I'm from Cincinnati, Ohio and I'm a second year masters student here at Dartmouth, studying earth sciences. Karina's focus more on the melt side of things and what she's going to do is look at these melt layers that we see in the core. Analyzing these cores I spend about four to five hours a day in zero degree Fahrenheit freezer. I get out a core and I cut it in half and what I do is store half the core from melting and then the other half i analyze it for the distribution of melt layers in the firm. Ice cores allow us to see annual layers in the snow just like the rings on a tree and so we can look at the thickness of those layers and figure out how much snow fell in each year going back in time. This ice is incredibly clean. This is some of the cleanest water on the planet and what we're trying to measure are the things that is not clean about it we're trying to measure the dust in it. The salt that comes in blowing from the ocean.

Any pollution that that falls in it. I'm primarily a snow chemist so I study climate change but the way that I study climate change is often using the chemistry in the ice cores. It's very small likelihood that anyone will ever go back to Greenland and get cores in these locations again that cover these years of accumulation and so we want to save these for future scientific purposes. It was really great group of people coming together each with their own skill sets. Each with their own science priorities and a mix of those personalities and those skillsets allowed our project to be really successful. The whole effort is to try and make our predictions of future climate change and future sea-level rise better so that we can prepare as a society..