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Beaufort Gyre Exploration Project 2016: Searching for Sea Ice: The End of Ice

October 12th, 2016 by Maria-Jose Viñas

By Alek Petty

View from a helicopter of our ice breaker, the CCGS Louis S. St. Laurent, taken after Ice Station 1.

View from a helicopter of our ice breaker, the CCGS Louis S. St. Laurent, taken after Ice Station 1.

The sea ice didn’t last long. We continued the hunt for sea ice suitable enough for another ice station – hoping for something thicker and more stable than last time around. Unfortunately our search was fruitless. The Woods Hole team tried for a quick installation of one of their ice tethered profilers (ITPs) –an ocean surface water profiler- on a thick ice floe that was only around 164 feet (50 meters) in diameter, but the ice was too ridged and porous to be suitable and the operation was quickly abandoned. They instead resorted to deploying two of their ITPs directly into the ocean from the side of the ship (this is less stable than wedging the surface buoy component of the profiler into an ice floe, hence why they’re called ice tethered profilers). Our hopes of getting out onto the ice again quickly vanished.

We were soon back to cruising through the marginal ice edge, which was dominated by newly forming young grey ice with the occasional floe of older, thicker, ice that had survived the summer melt season. We are now back to swaying our way through the high seas – not the kind of scene most people associate with an Arctic expedition. It was with a sense of deep regret that our time within the ice ended with nearly two weeks of the expedition still to go. For me, the expedition just isn’t the same without the sound of ice breaking reverberating around the ship (we’re on an ice breaker after all!)

Arctic sea ice extent as of Oct. 10, 2016.

Arctic sea ice extent as of Oct. 10, 2016.

We got a small dose of Internet after leaving the ice (I’m struggling to cope without it!) and I managed to get access to the National Snow and Ice Data Center website, which showed how the Arctic sea ice re-freeze has been really slow this year (see the sea ice extent image above), coinciding with very warm temperatures over much of the Arctic, including the Beaufort Sea. We’ve experienced temperatures only slightly below freezing on this expedition, so my thermals have stayed packed away. In the Beaufort Sea, the ice edge is clearly not heading south at any real speed, although as the temperatures are expected to drop further through the coming weeks and months, a refreeze across the entire Beaufort Sea should be inevitable.

Scientist Adam Monier looks out over Arctic sea ice.

Scientist Adam Monier looks out over Arctic sea ice.

Despite the lack of sea ice (and my associated despondence), the science was still operating at maximum speed. We had a talk from Adam Monier, a French microbiologist from Exeter University (United Kingdom) who talked about his efforts, along with collaborators from Concordia University (Montreal, Canada), to increase our understanding of the microbial communities of the Arctic Ocean. According to Adam, around 90 percent of the global ocean’s biomass is microbial (a mass equivalent to roughly 240 billion elephants!) and this was seriously underestimated as of only a few decades ago. He showed some fascinating results demonstrating how phytoplankton (a micro algae) can cope, and even adapt, to fast changing environmental conditions, like sunlight and access to nutrients – some of which can be linked to the changing Arctic sea ice state. There is still a severe shortage of Arctic data, and this cruise is trying to help fill in those gaps. As phytoplankton are the foundation of the Arctic Ocean’s food webs, understanding how they respond to rapid changes in environmental conditions will be key to understanding how the entire Arctic ecosystem responds to declining sea ice and changes in the Arctic Ocean. The expedition has been a great way for me to learn about the latest developments in Arctic science, and to appreciate how interconnected our various fields of research are.

Beaufort Gyre Exploration Project 2016: Searching for Sea Ice: Into the Ice

October 3rd, 2016 by Maria-Jose Viñas

By Alek Petty

Working on thin Arctic sea ice.

Working on thin Arctic sea ice.

After five days of cruising through open water, it was clear we had to change course and venture further north to find ice. The satellite imagery was showing ice above 76-77 degrees North (we were around 74 degrees North), and the ice edge didn’t seem to be drifting south at any real speed. After another few days voyage northwards, we thus finally found ourselves entering the Arctic sea ice pack. This wasn’t exactly a scene from the Titanic; the transition from water to ice was a gradual one, as the ice cover evolved from millimeters or centimeters of newly forming sea ice (nilas and grease ice), to thicker, consolidated ice floes (maybe a meter or two thick; 3.3 to 6.6 feet), which caused the ship to lurch and shake as it broke its way through.

Early stages of sea ice growth: nilas (top left), pancake ice (top right), young grey-white ice (bottom left) and first-year ice (bottom right). The top photos are courtesy of Jean Mensa.

Early stages of sea ice growth: nilas (top left), pancake ice (top right), young grey-white ice (bottom left) and first-year ice (bottom right). The top photos are courtesy of Jean Mensa.

Once we were well within the ice pack, the Woods Hole team was keen to get out onto the ice and deploy some buoys. This would be my chance to get out on the ice too, as I was helping lead efforts to collect ice thickness measurements and ice cores, to better understand the characteristics (like salinity, density and age) of this year’s Beaufort Sea ice pack. The microbial and microplastic scientists were keen to join in and collect their own ice cores, too, enabling them to take a deeper look at what else might be hiding within the ice.

The Woods Hole team leader flew out with the helicopter pilot early the next morning to hunt for thick ice, and seemed to find an ice floe thick and stable enough for us to work on. I joined them on the first science flight out a few hours later to set out our survey lines and coring sites, before our cargo was carried over and the rest of the team members joined us. It was soon apparent that the ice wasn’t as thick as we had hoped.

I drilled a few quick holes and the readings all came in at around half a meter, just above what might be considered safe to work on. Our polar bear guard, Leo, wasn’t too happy with the conditions either and soon found a few good sized holes and cracks circling us. We were under strict orders not to stray from the group and to test the ice for stability as we moved ahead. I’ve previously used data from satellites, planes, and sophisticated computer simulations to estimate the thickness of Arctic sea ice. Yesterday, I estimated ice thickness by hitting it with a stick.

Danger ice!

Danger ice!

It wasn’t quite vertical limit, and the group rebuffed my idea of roping together for dramatic effect, but there were still a few hairy moments when the odd leg found its way through the ice. Despite the added element of danger, all operations completed successfully and we hitched a lift back to the ship later that afternoon with our ice cores in tow. The Woods Hole team was working until last light to get their buoys prepped and ready to drift off through the Arctic. It was a fun, adrenaline-filled day of science, but I’d prefer it if we could find some thicker ice to work on next time around.

Beaufort Gyre Exploration Project 2016: Searching for Sea Ice: More Motion In The Ocean

September 27th, 2016 by Maria-Jose Viñas

By Alek Petty

lowres-1005

My journey up to the ship went smoothly and I even had time to observe the Northern Lights (Aurora Borealis) in full bloom during our overnight layover in Yellowknife (in the Northwest Territories of Canada). The following day, a Canadian Coast Guard helicopter transferred us from Kugluktuk airport onto the ship, and after another day spent refueling and replenishing the boat, we were finally on our way to the Arctic Ocean.

The Northern Lights.

The Northern Lights.

The Louis S. St. Laurent ice breaker.

The Louis S. St. Laurent ice breaker.

I actually spent the first two days of our polar expedition sat out on deck, enjoying the sunshine and views over the Amundsen Gulf. In the distance I could just about make out the mouth of the Mackenzie River delta – a key outflow of fresh and mineral rich river runoff into the Arctic. This shelf sea region is rich in wildlife, including beluga whales and even narwhals. We looked out eagerly, but only spotted a couple of lowly seals in the distance. Maybe on our way back we’ll have more joy.

On Saturday morning, we emerged into the Arctic Ocean proper —the Beaufort Sea! — where conditions were a bit less serene. In fact, one of the consequences of the diminished Arctic sea ice cover over the past decades has been an increase in Arctic Ocean waviness, as the lack of sea ice enables winds to more effectively whip up the ocean. Arguably one of the most distressing impacts of climate change for us unhardened scientists.

Despite the continued lack of sea ice, the water sampling exercises have begun in earnest. At each research station (a virtual station if you will, we just stop at a predetermined location in the ocean) a large metal carousel with various water samplers attached —a rosette, as we call it— is released, profiling the water column as it sinks to the bottom of the ocean, before being hauled back up to the ship for analysis.

A rosette deployment.

A rosette deployment.

There are around 50 stations in total that we plan on hitting during this expedition. The various scientists on board all have their own things their looking for in the water —plankton, bacteria, alkalinity, dissolved inorganic/organic carbon, micro-plastics (yep, they make it to the Arctic Ocean too), etc. You name it, we’re sampling it.

One of my tasks, along with Japanese scientist Seita Hoshino, is to profile the water column in-between theses stations using XCTD (eXpendable Conductivity Temperature and Density) probes. XCTDs provide a quick and cheap (well, about $800 per probe, so not that cheap) real-time analysis of the temperature and salinity of the water column while the ship is moving. I’ll try and show you an example profile in a later blog post.

We’re hoping to hit some ice soon, as for us ice observers there’s not a whole lot for us to get really excited about yet. It’s quite the contrast to the cold, icy conditions of my 2014 expedition thus far…

 

A Satellite Scientist Visits the Ice, Alaska 2016: Beachfront Resort

May 27th, 2016 by Maria-Jose Viñas

By Walt Meier

the house

I have arrived in Barrow, Alaska. It was an interesting flight up from Anchorage: the plane had seats only in the back half of the plane because the front half is used for cargo. That is because there are no roads into Barrow, so supplies need to be brought in by plane or, during the short summers, by barge. After a stopover in Prudhoe Bay, we arrived to gloomy skies, which are quite typical for this time of year. Temperatures are right around freezing. We are staying at the NARL, which originally was the Naval Arctic Research Laboratory. Various research groups and other activities –even a college– now share this facility.

The accommodations are spare, but comfortable. Most people are staying in Quonset huts (prefabricated huts made of galvanized steel), but I’m with four others in “The House”, which is more like, well, a house. We have a living room, kitchen, full bath, and four bedrooms. Because we have a kitchen, we are the base for meals where the whole group meets up to eat breakfast and lunch. Last night we all gathered for a light meal after arriving and, with 24 people, it got pretty crowded. But it was nice to catch up with old friends and meet new colleagues. Already the collaborations have begun as we informally discussed each other’s research.

The whole campus is on a narrow spit of land north of town sticking out into the Beaufort Sea. I can see the sea ice from the house. So you might say we’re staying at a beachfront resort! With the ice right out the window, it was tempting to take a walk out there last night. However, we were told to not go out on the ice until we get a safety orientation. The ice off the coast is landfast ice – ice that is attached to the coast, so it doesn’t drift with the winds. However, it can still shift with the tides, as evidenced by piles of ice ridged formed as ice got pushed together. So one doesn’t want to just run out on the ice without being familiar with the hazards. Oh, and there are also potentially polar bears roaming around – another very good reason not to go roaming off by oneself.

Our view of sea ice from The House.

Our view of sea ice from The House.

Now we’re heading off to our orientation session and introductory discussions where we’ll start learning about modeling, satellite data, and field observations. This afternoon we’ll take our first trip out onto the ice. When the week is over, each of us will have broadened our expertise beyond each of our core research areas and hopefully we may find new areas of research to collaborate on and advance our understanding of sea ice.

A Satellite Scientist Visits the Ice, Alaska 2016: A Satellite Scientist Visits the Ice

May 26th, 2016 by Maria-Jose Viñas

By Walt Meier

Walt Meier

Whenever I tell people that I’m a polar scientist or that I study sea ice, inevitably one of the first questions I’m asked is, “so, have you been to the ice?” I’ve always had to answer no. I’m a remote sensing scientist who works with satellite data. Other than a few aircraft flights over the ice several years ago, I’ve spent my career in front of a computer analyzing satellite images. When I’ve needed field data, e.g., to validate satellite measurements, I could always obtain it from colleagues. So there has never been any need for me to go out on the ice. And to be honest, spending days or weeks in the field, as many researchers do, does not have particular appeal to me – I like the comforts of my heated office! Nonetheless, I’ve always wanted to get out at least once in my career and see the ice close up, feel it crunching under my feet, hear it creak and groan as it strains under the winds and currents.

An image of sea ice in northwest Greenland, capture by NASA's Operation IceBridge.

An image of sea ice in northwest Greenland, captured by NASA’s Operation IceBridge.

Now I am getting that chance, thanks to a National Science Foundation funded Summer Sea Ice Camp workshop. I and a couple dozen fellow scientists are heading to Barrow, Alaska – the northernmost point in the United States at 71 degrees N latitude – to partake in a unique project. The goal of this project isn’t specifically to collect data (though I hope that some of the data we collect will be useful), but rather to foster communication between remote sensing scientists like myself, sea ice modelers, and field researchers.

While there is a lot of collaboration in the sea ice community in terms of sharing data and results, scientists tend be silo-ed within their own area of expertise when it comes their actual work. Modelers focus on model development, validation, and results. Remote sensing folks like myself analyze satellite data. And field researchers collect and analyze in situ observations. Partly this is simply due to time – just focusing on one area keeps one plenty busy. But it is also partly due to a lack of communication. For example, I know a bit about modeling, but I don’t really understand the details of how a sea ice model is put together, how it can and should be used. Similarly, while modelers often use remote sensing data to compare with their model results, they don’t often understand the capabilities and limitations of satellite data. This can lead to under use or misuse of the data. And neither modelers nor remote sensing scientists may have much understanding of how to best take advantage of in situ data.

The goal of this workshop is to bring the three groups together for a week to talk and work with each other to better understand each of the three specialty areas and how perhaps the three groups can better work with each other to advance our understanding of sea ice. So now I’m on my way to Barrow, Alaska, looking forward to helping others understand satellite data, as well as running sea ice models and feeling that crunch of ice and snow under my feet as I collect data from on top of the Arctic Ocean. More in my next blog post from Barrow!

Notes from the Field