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Post from a Scientist: Things that Melt Out of a Glacier

My first experience working on a glacier in the Canadian Arctic took place on Axel Heiberg Island, in Nunavut Territory. I realize that White Glacier isn’t the most exciting name for a glacier – in this case, a 14 km river of ice flowing from 1800 meters at the highest peaks to nearly sea level – but it is certainly an exciting and beautiful place to work! For thousands of years, precipitation has fallen as snow high in the mountains surrounding White Glacier, and this accumulation of snow builds over the years when the temperature remains cold and below zero due to the high elevation. Over time, the snow is compressed into ice and eventually flows down the mountains through valleys that act as channels for the ice. At lower elevations in the valleys, the temperature is warmer and the ice melts, forming long braiding streams in front of the glacier that eventually flow to the ocean, thereby contributing to global sea level rise. This is the story of a glacier: grow with snow, shrink with melt.

As a 3rd year PhD student (that’s like grade 20!) my science project is to study changes to White Glacier due to the imbalance between the amount of ice gained from snowfall, and ice lost due to melt. Over the past two decades, White Glacier has mainly shown that it loses ice every year, and in 2012 it lost the most ice in any year on record. White Glacier is one of only 5 glaciers in the Canadian Arctic that is studied in this way in order to tell us how Arctic glaciers are responding to climate change. This work is part of a long-term program that was started in 1959 by a group of researchers that founded the McGill Arctic Research Station.

Working at a historic research station has been really interesting. We have a museum of old corned beef cans from the 1960s, and I often find artifacts melting out of the glacier, including old weather instruments, tools for measuring the temperature of the ice, old sleds and skis, bamboo poles for measuring ice melt, and even a pair of wooly socks! It makes me realize how far we’ve come in terms of technology, and at the same time how similar our techniques still are.

– Laura, University of Ottawa, Canada

The Jokulhlaup

If there is one take-away from this Glaciology Summer School that I would want everyone to know (of those who hadn’t already known), it’s that glaciers themselves are a force of nature. Their presence can alter an environment, and their disappearance can affect the environment. We went on a different trek to the glacier front, led by Mike Loso of Alaska Pacific University Anchorage, and saw the glacier’s effects everywhere, from the rocky riverbed left behind as the glacier retreated, to the layers of the mountainside sloping down to the glacier bed below, to the white rock that had been scourged by the glacier…

Here is the Kennicott rive flowing towards us. The treeline/ridge is the terminal moraine (the accumulated soil at the edge of the glacier) during the last little ice age. The riverbank on the left is eroded most years by the annual Hidden Creek Lake flood, aka the “jokulhlaup”, (there’s a new word for most of us) and that boulder was still in that bank as of just a couple of years ago).

Mike showed us this plant, called Dryas drummondii (in the photo is the plant’s seed head). The cool thing about this plant is that it is one of the early species to colonize newly un-glaciated terrain. And it’s a “nitrogen-fixing” plant, which means it takes atmospheric nitrogen and turns it into nutrients, which then benefits the soil for other plants.

There may not be white in front of us, but there is a glacier. Here we are looking out at debris-covered glacier ice. This meltwater pond is next to where Kennicott River is coming out of the ice, and on the right is Bonanza Ridge, home to the old copper mines that used to dot this landscape.

We climbed this beautiful glacier-scoured bedrock which lies near the toe of the Kennicott Glacier. The exposed sediment at the top among the trees is also glacier till (unsorted, unlayered sediment) that was deposited sometime during the last ice age.

This tree has seen it all. This spruce stump, still in growth position, grew in front of the Kennicott Glacier in the late 1500s. It was overrun by advancing glacier ice in the 1600s, where it remained until the late 1900s, when it was exposed in this river channel as the Kennicott Glacier retreated. And it’s still here.

Crampons: A Glaciologist’s Best Friend

When I think of hiking or climbing, the thought of going up instinctively sounds harder than going down. And I would think I’d be much more likely to slip and fall walking on ice as opposed to walking on rock. Not true. Glaciers are ice, which of course is slippery. But then there are the moraines which may be on the edges of the glacier, or on the glacier surface itself. Moraines are accumulations of rock and soil that have been formed into mounds by the movement or melting of a glacier. Now think about a steep mound of ice, covered in a layer of loose rocks and gravel. Trying to get down the slope without injury may involve any manner of trying to “surf” down the gravel, or taking baby steps as quickly as possible, to keep your feet moving faster than the gravel can slide. Even if you’re successful, once you’re down, there is the small matter of getting back up a steep slope of slippery rocks, now with gravity working against you. (Yes, I may have slipped and fell once or twice…)

All of that made me appreciate even more the “tool” that help glaciologists move more safely as they conduct their research on the ice. Crampons kind of look like a weapon, but these spikes can be lifesavers, literally and figuratively, as they dig into the ice, making each step more stable. A few suggestions for wearing crampons: walk like an old movie cowboy, bowlegged and lifting your knee as you take each step. Because nicking your pants or boot on the spikes, or catching the toe spike in the ice as you step, can take you down. (Yes, my nice ski pants may have a tear in the ankle…) It’s just too bad that crampons and rocks don’t mix.

Post from a Scientist: Himalayan Glaciers

Wow! When I was a kid and hiking on Sundays with my parents – I always marvelled at the landscape and especially at the mountains…and often I was left behind. 🙂 From then, I wanted to discover the world and wanted to know why things are how they are. And this is what I do today.

I’m Patricia and I am a PhD candidate at the University of Potsdam in Germany. I finished my Masters in Earth Sciences in 2011 at the Federal Institute of Technology in Zurich (Switzerland). My focus area of interest is the influence and interplay of tectonic processes and climate (precipitation, glaciers) on landscape evolution. During my Masters I therefore mainly focused on geology (structural geology, sedimentology, paleoclimatology). My current PhD project, called “Competing influence of glacial and fluvial erosion in the NW Himalaya, India” still covers some of these aspects. It focuses on exhumation of bedrock to the surface in the northwest Himalayas, and if this is influenced by climate or tectonics. This part of the Himalayas is still glaciated and influenced by rain and snow, but also by glaciers. The complexity of the interplay of the climate and tectonic processes makes it to an interesting area of study. Apart from learning new geo-chronological methods, I also “slipped” into the field of glaciology, which so far I have only just touched on. I want to know if glaciers, in the interplay between regional tectonics and climate, are able to impede or accelerate erosion?

In the Himalayas, glaciers are important for humans as they store freshwater for an entire region. But the retreat of glaciers does not only influence water availability. It can also cause devastation due to glacial lake outbursts, which can affect agriculture. Reading the landscape to reconstruct former glacial stages and the consequences of glacial retreat, as well as the prediction of future events, may help people in the region to prevent more damage.

In my research, different aspects are taken into account when you discuss results. On the one hand, long term evolution hardly affects people in the short term, but is very interesting. On the other hand, climate questions are certainly related to glacial and interglacial cycles. Glaciology can help us to understand these patterns better. At this summer school, my aim is to enhance my knowledge and understanding of the glacial system, so that I am able to describe and explain observations I made in my field.

– Patricia, University of Potsdam, Germany

Fun in McCarthy

Students in this Glaciology Summer School course consistently have their noses to the grindstone, so to speak, with lectures and project work each day, but in the evenings, there is a little time to relax (and it stays light outside very late). McCarthy, for being a tiny town with a population only in the double digits, offers a fine variety of ways to take a break. Sometimes it might be more along the lines of what you might have in a bigger city (like live music), and sometimes you have to be creative and make your own fun (like swimming in a chilly glacier-fed lake). My personal favorite is the fact that McCarthy had a town softball game on Friday night, when everyone in town is there to either play or watch, all within sight of a glacier looming in the mountains above. That’s not something you do every day. Neither is a “Zombie Prom,” currently advertised on a white board outside the town saloon for next Friday. All in good fun in McCarthy.

mini-P1000728 — Swimming in the glacier-fed lake…

mini-SAM_2498 — Amazing live music (Deep Chatham) with upright bass, steel guitar, fiddle, and accordian…

mini-SAM_2153 — Playing softball with the whole town…

mini-SAM_2172crop — Watching the softball game with locals, complete with beautiful music…

mini-SAM_2149 — …all with a glacier watching over us.

Post from a Scientist: The Climate Crystal Ball

Have you ever looked at a landscape and thought to yourself… How did this happen?! … Why is this hill here? … Why do these rocks look like this? … What does it all mean?

My job is to look for clues in the landscape that indicate the former presence of glaciers. Glaciers are masses of ice that flow downhill from mountain tops, where it is cold enough for snow to remain on the ground all year round. Rocks fall on the surface of glaciers and are transported to the glacier margins where they accumulate in elongated, sharp-crested ridges (as in the photo). These ridges are called moraines, and they can remain in the landscape long after the ice melts away. When I find moraines in a location where no glaciers currently exist, I ask myself these questions: (1) Why did a glacier used to be here? (2) When was it here? (3) Why is it no longer here?

I am here at a glaciology summer school in Alaska, USA, to learn about what causes glaciers to grow and shrink. Temperature is a key control as it determines how much precipitation falls as snow rather than rain in winter, as well as how much snow and ice melts in summer. When temperatures remain stable for a many years, glaciers eventually reach an equilibrium state, where input of snow equals output by melt, and the glacier length remains stable. If temperatures increase, then less snow may fall and/or more melt may occur, causing the glacier to retreat. If temperatures decrease, then more snow may fall and/or less melt may occur, causing the glacier to advance. As moraines represent former glacier lengths, they contain important information about past climate change.

My research focuses on two volcanoes in central North Island, New Zealand – a long, long way from Alaska! I have multiple moraines in several catchments on these volcanoes, which document former glacier length changes. I have dated these moraines using a technique known as “cosmogenic surface exposure dating.” This technique measures the accumulation of rare elements, produced by exposure to high-energy particles that come from outside our solar system and reach the Earth surface. The moraines on these volcanoes range in age from 200 to 60,000 years old. Now I am using a computer model that simulates the growth of glaciers under different climatic conditions. I input different temperatures to try to recreate the former glacier lengths, as indicated by the moraines I have found. Putting the moraine ages and model results together, I end up with estimates of how much colder it must have been in New Zealand at a certain point in time.

I know what you’re thinking … you’re thinking “who cares how cold it was thousands of years ago?” Well, that’s a great question. These results are important for several reasons. For example, they provide an important test for computer models that try to predict future climate change. If these models can recreate past changes, then we have increased confidence in their predictions for the future. You can think of this as cleaning the climatic crystal ball, making it easier to look into the future and see what Earth’s climate may be like for your children and grandchildren.

– Shaun, Victoria University of Wellington, New Zealand

mini-blog_Shaun — Here I am on a moraine at the side of a former glacial valley that drains away from the active volcanic cone of Mt. Ngauruhoe in New Zealand.

All Hands On Research!

What exactly happens when the temperature of water drops below the freezing point? (Do you think everyone knows?) What does a little wind-up gadget remind you of? (Do you think everyone would have the same answer?) As science communication instructor on this Glaciology Summer School in Alaska, I presented these kinds of questions, among others, during the continuation of my science communication workshops. My goal for this session was to have everyone identify the main points of their research that are the most important for the public to understand, and then to lead them through the process of developing a concept for a hands-on activity, related to their research, that could be led in a science museum or classroom. The activity could be anything from a demonstration to multi-person game play to a problem-solving challenge.

mini-SAM_2534 — Helping each other brainstorm activity ideas

It’s not easy. When you know or understand something well, it’s sometimes hard to know where to “aim” your descriptions when talking to someone who is not a fellow scientist in your field. But think about how much difference it could make, if any time you met a scientist in an elevator, on an airplane, or in a classroom, if you (adult or child), walked away with a little bit more understanding, or better yet, perhaps even inspiration to learn more.

Leading up to our exercise time when our student scientists would be developing their activity concepts, I had them “draw their research” to really get them to narrow down their thoughts to a simple picture. Paper and colorful markers seem to autompatically make things more simplified, and more fun. Here are some of their drawings, and check back to see what activities they came up with!

mini-SAM_2730 — Identifying and quantifying glacier base conditions using seismology, and understanding ice streaming and shutdown

mini-SAM_2731 — Analyzing observed and modeled changes in ice and snow cover, its relation to climate, and effect on sea level rise

mini-SAM_2733 — Modeling glacier changes to see how climate change might affect glaciers and water resources in the future

mini-SAM_2734 — Studying the erosion in glacier areas, and how it is influenced by climate and tectonics

Post from a Scientist: Water Slides!

mini-SAM_2624 — On the edge of a glacier

Can you imagine a continent as big as the United States covered with ice more than four times as thick as the tallest building you have ever seen? If that is hard for you to picture, you are in the same boat as I was when I decided I was interested in glaciology. It was my curiosity as to how things as large as the massive ice sheets covering Greenland and Antarctica can move and rapidly change, that made me want to study glaciers. Knowing that through sea level rise these changes would affect people throughout the globe, perhaps even within our lifetimes, is the little bit of connection to something closer to home that continues to motivate my work.

One of the biggest surprises to me when I started in glaciology was the ease, using satellites, with which we can get information about the way the surfaces of the ice sheets are changing. On the other hand, there are very basic things that we understand fairly poorly about both the basic physics of how ice flows and about things which take place underneath the ice. For example, ice is pretty easy to look through if it is small, like an ice cube in a glass, but when it gets thick and full of bubbles you cannot see all the way through, like ice on many lakes in winter. We have some tools to overcome problems like these, but basic things like the height of the land underneath the ice sheets is something that is difficult to measure, and we do not know very finely.

My research tries to take advantage of the recent data that are available for one particular group of glaciers in Antarctica. I use these data to understand how these glaciers change and to try to gain insight into some of the processes in the ice which are not directly observable. I’m especially interested in how other earth systems – the ocean and atmosphere in particular – affect how the ice sheets evolve. Melting driven by the warm ocean causes rapid thinning where ice from the continent meets the ocean, and the flow of the ice is very sensitive to these changes. I try to better understand how small changes in melt will affect how things change on a larger scale. In some ways this is like coming down a waterslide into a pool. If there is more water, you will slide faster. If you arch your back so you scrape against the slide less, you will move more quickly. My research is like trying to figure out, depending on much water there is and what part of you is touching the slide, when you will splash into the pool and cause the water level to rise.

– David, University of Washington, Seattle, USA

Project! Taking Antarctica’s Temperature

mini-SAM_2502 — Working on projects in McCarthy’s old hardware store

Onward with Glaciology Summer School projects! Firsthand data, like when you can actually be in a place and measure the temperature with a thermometer, is always useful. But what happens when you want to take the temperature of a place that is one of the more remote places on the planet, like Antarctica? This project focuses on the Antarctic peninsula, a dynamic area which has changed a lot in the past decade, especially with the collapse of the massive Larsen B ice shelf in 2002. We are using microwave signals from a satellite as well as ground-based weather station data to understand the relationship between climate and Antarctic melting. Microwave frequency signals are used because ice and snow reflect a significantly larger amount of microwave radiation than liquid water. Since water melts at close to 0 degrees Celsius (depending on pressure and purity), melt detected by the satellite is strongly related to increases in surface air temperature above freezing. Therefore, using weather station data we are able to confirm this relationship between temperature and melt. Using satellite data to detect the timing and spatial distribution of melt is particularly useful in locations like Antarctica, where taking sufficient ground measurements is not very feasible.

Our next step will be to compare the melt that was detected using satellite data with melt as modeled by a regional climate computer model, to contrast the strengths of each method for accurately detecting melt. At the end of the day, what we want to do is see how well global climate indicators relate to the melt events on the peninsula. These may help explain why melt events may be larger or smaller on any given year, and when studied over time, may offer a “big picture” of how climate changes affects melting processes.

– Thomas and Tyler

Willy the Box Turtle: Our Miami Mascot Travels to Alaska!

mini-SAM_2375 — Willy the Turtle from Miami, on an Alaskan glacier

If you didn’t follow along with us during last year’s Arctic Ocean expedition, let me introduce you to Willy the Box Turtle. Willy served as a kind of diplomatic mascot for that expedition, to show that even though Miami is about as far from the polar regions as you can get, changes in climate affect us all globally, and what happens in one place can affect other places. Willy came along on this Glaciology Summer School, where we are as we speak, to continue that mission, because glaciology is a prime example of the kind of research that illustrates that point. All of the scientists here study glaciers, but how and why glaciers grow, melt, and move depends on climate and environmental conditions. And when glaciers melt, it affects sea level rise and freshwater sources for communities around the world, both human and animal. For turtles, rising sea levels affect their coastal nesting habitats, and increasing temperatures can even have an impact on the gender ratio of hatchlings. So Willy had to come out and see the glacier for himself! (Don’t worry, he is a stuffed turtle.)

I also wanted to share a poem I received from a reader of blog during the Arctic expedition (who prefers to remain anonymous) that I want to share here again. I think it’s a really lovely way to sum things up.

A polar bear from the Arctic named Chilly
A turtle from Miami named Willy
Who would ever think?
Is there really a link?
Oh Yeah! It’s mankind we’ll name Silly.

So if the ice is crucial to Chilly
And water equally so to Willy
If we all hold the key
‘Cause we’re the powers that be
Isn’t it time to stop being “Silly?”

-Anonymous

mini-DSC_0699 — Me and Willy, last year on our expedition in the Arctic Ocean