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Nansen Ice Shelf, Antarctica 2015: First Data Collection Day

December 14th, 2015 by Maria-Jose Viñas

By Christine Dow

Credit: NASA/Christine Dow

Credit: NASA/Christine Dow

The big day had arrived. We were due to fly to our tiltmeters to collect the data that they had been gathering for two weeks. once this was the first time we had ever set these instruments up in the field, all fingers were crossed that we had been precise enough in initially leveling the meters so the data were in range and also that the solar panels hadn’t ended up covered in snow.

We had a spectacular flight, cutting over the end of Priestley Glacier and skirting helicopter-sized crevasses on the mountain behind our field site. Despite a bit of wind on the Nansen ice shelf, it was as calm on the Comein Glacier as it has always been for our visits. It’s such a peaceful, sheltered spot that I feel a holiday cottage wouldn’t be amiss. Perhaps too long of a commute for an average Friday afternoon, however.

Credit: NASA/Christine Dow

Credit: NASA/Christine Dow

One of the tiltmeters (which are in black boxes) had become exposed and, because black materials absorb heat whereas white materials reflect it, had caused a bit of local melt which had trickled down the side of the box and refrozen. The upshot of this was that the entire box, battery, and straps were encased in some pretty solid ice. Fun! Commence some delicate hacking with ice axes so that we didn’t snap the wires coming out of the box. Finally having reached the interior, we nervously extracted the SD card and Ryan pulled the data off onto the computer. Success! Some excellent (and exciting) looking data showing tidal cycles. Tiltmeter two was easier because it hadn’t caused local melt of the snow so we could quickly retrieve the data. Again, some very interesting outputs. We want to thank John Leeman, an engineer from Penn State, for building us some happily working tiltmeters. Of course having disturbed the tiltmeters I had to reset them back to full level, which required sitting for 10 minutes enjoying the view while very delicately adjusting the little leveling legs.

We had just enough time to collect data from one of the GPS closest to the tiltmeters. All looked well apart from our tethers, which had come loose because of melt on the surface. We had one bamboo tether and one metal peg. The metal had heated up and melted a groove in the ice as it was pulled along, whereas the bamboo had stayed where it was supposed to. We tightened the wire as much as possible but we would have to return to this site with some more bamboo later.

Credit: NASA/Christine Dow

Credit: NASA/Christine Dow

Dinner back at base was a happy affair, having achieved success for at least three of seven of our instruments. The chefs had even made some pizza for us, which was a nice treat. The only unfortunate aspect of the day was that I had forgotten that in areas with 24 hour sunshine and highly reflective snow surfaces it is essential to put sunscreen up your nose as well as on it. Burnt nostrils are not fun, but they’re worth it for some nice data.

Nansen Ice Shelf, Antarctica 2015: Equipment check-in and Drygalski adventure

December 8th, 2015 by Maria-Jose Viñas

By Christine Dow

Credit: NASA/Christine Dow

Credit: NASA/Christine Dow

The Nansen Ice Shelf, where we have installed our GPS, is notoriously windy. This is clear from the blue ice on the surface and complete lack of snow, which gets rapidly swept away by katabatic winds (winds driven down from the glacier towards the sea by differences in pressure induced by the cold glacier air). This means that wandering around while setting up the GPS requires spikes for your shoes or else it would be like slipping around on a scalloped ice rink. To prevent the equipment from coming loose and blowing down the ice shelf into the sea, we have a set-up where wire tethers hook our solar panel and GPS box into the ice. However, it’s always encouraging to check that the systems are holding up to the elements, so we took advantage of a helicopter flight heading in that direction to check on the field equipment. It was all still there, happily recording data.

Credit: NASA/Christine Dow

Credit: NASA/Christine Dow

Luckily for myself and Ryan, the flight we were on was heading to the Drygalski Ice Tongue. This is a strange feature that can even be seen when looking at maps of the whole of East Antarctica. It is a floating 12 mile-wide section of ice from David glacier that sticks out 50 miles into the ocean and impacts sea ice freezing and water circulation in the bay behind it. Our approach to the ice tongue was spectacular as it headed off into the distance. At the side of the tongue, steep ice cliffs dropped into the ocean with the interaction between subsurface ice and the ocean water creating the most amazing shade of blue. We could spot groups of Adélie penguins on the remaining sections of sea ice next to the Nansen ice shelf and the Drygalski Ice Tongue.

Credit: NASA/Christine Dow

Credit: NASA/Christine Dow

The most exciting moment was when our sharp-eyed pilot, Dom, spotted some whale spouts. We swung back around and saw four whales swimming around and breaching at the ice margin. They were Arnoux beaked whales, as we later identified, and looked nothing like any whale I have seen before – a little like very large dolphins with long pointed noses. These whales can dive for up to an hour so likely were just having a breather before heading under the ice. This was perhaps my favorite moment of the trip so far.

On the ice tongue we landed to check and download data from GPS stations that our Korean colleagues had installed several years before. We had a great view back across the bay towards Jang Bogo with Mt. Melbourne in the background. The second GPS site was fairly close to the front margin of the ice tongue and so Ryan and I had a geeky moment getting excited about being at the edge of one of the most bizarre ice features in the Antarctic.

It was a great day overall. All our stations were still standing, we saw wildlife, lots of ice and we were even back in time for a noodles and kimchi dinner.

Nansen Ice Shelf, Antarctica 2015: Life at Jang Bogo

December 3rd, 2015 by Maria-Jose Viñas

By Christine Dow

Jang_Bogo

Day to day life at the base station is varied primarily by timing of our field expeditions. We’ve had some very busy days getting equipment ready, deploying and checking our gear. In between, however, we are essentially operating as we would do at the office. We have set up base in the ‘Extreme Geophysics Group’ laboratory joining seven Korean scientists. Work tends to happen six days a week, with Sunday as a break (and no 7 am wake-up music!). Also on Sundays there are sometimes mini-expeditions. For example, a group of us walked a couple of miles over to Gondwana, the German base, which is semi-inhabited (two people are there at the moment keeping things ticking over). We were hoping for some “Kaffee und Kuchen” (coffee and cake) but couldn’t find anyone around. Instead we looked at rocks ejected from the nearby volcanic Mt. Melbourne, found some lichen and watched the many skuas (seabirds) flying around. We also ventured down onto the sea ice and found a nice ice slide which entertained us for a while (who said scientists couldn’t be silly).

Seal1

Last Sunday, Ryan and I joined a short expedition over to Mario Zucchelli, the Italian base. Recently a crack, or lead, has opened up in the sea ice so it’s no longer safe to drive the heavy Piston Bully tractors over. As an alternative, the Koreans and Italians both drove up to the crack and we exchanged passengers by hopping over the gap (it’s not really that big). There were some nearby Weddell seals hanging out near the open water, which we got a good look at. You have to be careful not to get distracted and wander into one of the seal holes which are just a bit darker than the surrounding ice – that would be a chilly surprise!

 

Mario_Zuchelli
The Italian base was built 31 years ago so looks a bit more worn in than Jang Bogo but is very cosy inside. We were given a tour and fed some excellent espresso and gelato. It was really interesting to see the differences between the two bases and even the landscape. Despite being only 6 miles (10 km) apart, the rocks around Mario Zucchelli look much more weathered and eroded compared to much rougher terrain at Jang Bogo, perhaps due to the closer proximity of the volcano to the South Korean station.

LifeatJB3

At Jang Bogo, another big difference is the food and is the subject of much conversation with the Western scientists. There has been a large range of foods produced which keeps things interesting. A lot of it is a surprise since we can’t read the Korean menu, although being able to cope with spicy food is definitely an advantage (Ryan is better with this than I am). By far the best meal was Korean BBQ evening where we cooked meat and prawns on a hotplate right on the table and had a brilliant array of salad leaves (grown in house) and sundries to eat with the meat. What a meal!

Nansen Ice Shelf, Antarctica 2015: Second Day of Installation

December 1st, 2015 by Maria-Jose Viñas

By Ryan Walker

TM1_pic

Our second day of installing equipment was on November 21. After a cloudy day off, we had perfect sunny weather.

We began by installing our two tilt meters at Comein Glacier, which flows into the Nansen Ice Shelf through a small inlet just north of the much larger Reeves Glacier. Most of an ice shelf floats freely up and down with the ocean tides, and the ice only flexes in a relatively narrow band between the floating ice shelf and the grounded glaciers that flow into the shelf. We chose this location (about 35 miles upstream of the ice shelf front) because the flexure zone is particularly wide (over three miles) and there is a broad strip of over 900 yards of ice that floats at high tide and rests on the ground at low tide. (We know this thanks to satellites that measure the height of the ice surface using lasers or radar, and to comparisons between satellite radar images that detect ice motion.) As it turned out, this area is the most spectacular place we’ve yet visited, surrounded by gleaming white snow- and ice-covered peaks.

Installing tilt meters is rather tricky, since the instrument has to be almost perfectly level. After two Korea Polar Research Institute safety guides checked the area for crevasses (large cracks in the ice), we dug through about two feet of snow before finding solid ice. To keep the tilt meter level, we constructed a table from a piece of plywood supported by three aluminum pipes drilled into the ice. The pipes passed through holes drilled in the plywood, which rested on hose clamps fastened around the pipes. By adjusting the hose clamps, we leveled the plywood before placing the plastic case containing the tilt meter on top of the table. The tilt meter itself has a triangular base with three adjustable screws so it can be leveled on top of a flat plate at the bottom of the case. To do this, I had to attach a cable from the tilt meter to my computer to get readouts of the angles while Christine very carefully adjusted the screws. Once we were satisfied that the instrument was level, we hooked up a solar panel and battery for power, just as we did for the GPS stations. Finally, we buried the case and table in the snow to prevent any melting of the ice supporting the table, which could put the instrument out of level.

GPS_installday2

After sandwiches and coffee in beautiful sunny weather (certainly the most scenic picnic lunch I’ve ever had), we took some time for a school outreach project that Christine will tell you about. Then we flew back out onto the Nansen Ice Shelf (which is much windier) and installed our two remaining GPS stations with no trouble (other than a chilly half hour waiting for the helicopter to return) to complete a successful day in the field. Now we need to wait about two weeks before collecting data, so that we can see what happens to the shelf as the ocean tides go through a full cycle from spring (largest difference between high and low tide) to neap (lowest difference).

TM2_pic

Christine says: I’m involved in a program coordinated by the United Kingdom Polar Network called “The Antarctica Day Flags Initiative”. School classes design flags for Antarctica Day (which is December 1, the anniversary of the signing of the Antarctic Treaty in 1959) and then scientists and researchers take them to the Antarctic and take photos of them out in the field. I had 21 flags from two schools (Yardley Hastings and Northrepps Primary) so we attached these to poles and took some pictures in front of some beautiful icy cliffs with our Korean colleagues.

NP_picture YH_picture

Greenland Aquifer Expedition: That’s All, Folks!!!

April 23rd, 2014 by Maria-Jose Viñas

By Ludovic Brucker

After an unexpected phone call from the helicopter pilot on Easter Sunday, Ludo and Clem ended the second season of the Greenland aquifer campaign, with the support of Susan, Rick, Lora, Bear, the weather office, and many others. Thanks all for this Easter bunny.

After an unexpected phone call from the helicopter pilot on Easter Sunday, Ludo and Clem ended the second season of the Greenland aquifer campaign, with the support of Susan, Rick, Lora, Bear, the weather office, and many others. Thanks all for this Easter bunny.

We still wonder whether our campaign was successful, or fair. For sure, it was a mix of good and tough times.

The pluses, making our campaign a good time:

– We’re back from our field site, healthy and with all our fingers and toes!

– We set up an almost perfect camp, limiting drift considerably.

– Our two tents survived 65-knot winds!

– We had saucisson (dry cured sausage), and cheese for fondue!

– No polar bear smelled our food!

– We collected over 17 miles (28 kilometers) of high-frequency (400 MHz) radar data, including 12 mi (20 km) in one day (equivalent to half a marathon!)

– Along a 1.24-mi (2-km) segment of the 2011 Arctic Circle Traverse, we deployed 5 radars operating at 400, 200, 40, 10, and 5 MHz.

– We installed an intelligent weather station developed by the group at IMAU, in the Netherlands.

– We drilled down to 28 feet (8.5 meters) to record the density and stratigraphy of the ice layers.

– We have GPS taken positions during a week, which will help us calculate the velocity and flow direction of the ice in this basin.

The minuses, making our campaign “different”:

– Ten days of weather delays before the put-in flight to our ice camp location.

– Rick could not make it to the field with us.

– We never had three consecutive half days with weather suitable for work.

– Getting a sore throat from shouting to hear each other less than a meter apart.

– During the one day of great weather, we tried to drive down a pilot tube to install a piezometer in the aquifer. This technique is adapted for ground water found within rocky soils. It was the first attempt to do it in the Greenland firn. Driving the metal pipes in the snow through the ice layers was a nightmare, we had to pound on those pipes really hard to make them go through the thick ice layers and we ended up breaking them. At one point, we thought it was broken slightly deeper than 6 ft below the surface, so we dug a pit down to fix it. Well, it turned out that the broken piece was actually 13 ft down — we spent the only full day of great weather breaking our equipment.

– We ran out of cheese for fondue, and of saucisson.

– Sunscreen was completely useless this season.

The “funny” stuff:

– 30 m/s wind is brutal, though not necessarily hilarious.

– High-wind speed does not make the clock spin faster, only the anemometer.

– Supporting text messages and jokes from our family, colleagues, and office mates.

– Attempting a radar survey with a sled taking off every other gusts.

– Calling the Met Office for a weather forecast: “Hello! Since it’s windy here we are wondering what will happen in the next 36 hours.” “Yes, I can confirm that you are experiencing wind.” “Thanks so much for the confirmation, but there was no room for doubt.” “Oh, but it’s a nice spike on the computer screen! It won’t blow more, but it won’t stop soon. Be careful out there”. Patience with Mother Nature is the #1 fundamental.

– Coastal storms from the East might be our favorite storms on the ice sheet: wind stops, and temperatures increase, but it snows, snows, and snows.

– Sixteen feet of seasonal snow is deep, especially with the top 2 feet of fresh snow becoming harder and harder as they it gets compacted by the wind.

– Excavating 1765 cubic feet of snow between 8pm and 11:30pm (you got to use the weather window whenever you have it.)

– The frost all around our sleeping-bag head every morning.

– The 40 hours laying down in the sleeping bag.

– The melody of the wind on our tents and through the bamboo sticks we stuck around them.

– Using the sleeping bag to store hats, balaclavas, gloves, socks, boot insulation, contact lenses, tooth paste, sun screen (it was nice to dream about the day we would need it), batteries, head lamp, snacks, water bottles (ideally liquid and not spilling.)

– The pilot phone call at 8 am on Easter Sunday: “Good morning, happy Easter! Don’t go for a ski strip today, we will come pick you up in 3-4 hours!”

This was the synopsis of our 13-day adventure on the ice sheet. Even though we have been pulled out from the ice sheet, we still have some work to do, such as cleaning and drying our cargo and repackaging it for shipping to either Kanger, or the US.

Now, we would like you to enjoy some photos taken in the field. Thanks again for spending some times reading the blog and following us! Until the next campaign, enjoy each season and stay warm! As we say in French: “En Mai, fait ce qu’il te plaît!” In English, it translates to something like: “In May, do as you please!”. Yup, we’re heading back to the office and will hide behind a computer screen for the months to come.

All the best,

Ludo & Clem

(Left) As weather-delay days continue to keep us in town, Rick calls the weather office to assess whether we can afford to spend more days waiting to be deployed on the ice sheet. (Right) The saddest moment of our campaign, when Rick had to remove his gear from our cargo because he wasn’t coming with us to the field.

(Left) As weather-delay days continue to keep us in town, Rick calls the weather office to assess whether we can afford to spend more days waiting to be deployed on the ice sheet. (Right) The saddest moment of our campaign, when Rick had to remove his gear from our cargo because he wasn’t coming with us to the field.

(Left) At the Tasiilaq heliport, Ludo waits for our put-in flight on the cargo. (Right) The Air Greenland B-212 helicopter with blue skies and high clouds. After 12 days of patiently waiting, it looks like it’s a go!

(Left) At the Tasiilaq heliport, Ludo waits for our put-in flight on the cargo. (Right) The Air Greenland B-212 helicopter with blue skies and high clouds. After 12 days of patiently waiting, it looks like it’s a go!

Flying over the sea-ice covered Sermilik fjord to reach the ice sheet.

Flying over the sea-ice covered Sermilik fjord to reach the ice sheet.

Getting closer to the ice sheet, flying over crevassed tributary glaciers.

Getting closer to the ice sheet, flying over crevassed tributary glaciers.

(Left) Our cargo, dropped almost two weeks ago, got buried under 2 feet of snow. But all the pieces were there! (Right) The B-212 landed near our cargo for a final move to the ice camp location.

(Left) Our cargo, dropped almost two weeks ago, got buried under 2 feet of snow. But all the pieces were there! (Right) The B-212 landed near our cargo for a final move to the ice camp location.

Approaching our camp site.

Approaching our camp site.

Minutes after the B-212 had left Clem and me on the ice sheet, we were already shoveling the fresh snow to install our cooking and sleeping tents before dark. This was no time for play, this was no time for fun, there was work to be done.

Minutes after the B-212 had left Clem and me on the ice sheet, we were already shoveling the fresh snow to install our cooking and sleeping tents before dark. This was no time for play, this was no time for fun, there was work to be done.

Our first pretty sunset in Greenland. In one month, we saw two of them.

Our first pretty sunset in Greenland. In one month, we saw two of them.

Early morning selfie! Not fully ready yet to put our cold weather gear on.

Early morning selfie! Not fully ready yet to put our cold weather gear on.

Shoveling, a typical activity at camp. Luckily this year we did not have to shovel too much to maintain our tents.

Shoveling, a typical activity at camp. Luckily this year we did not have to shovel too much to maintain our tents.

With the amount of fresh snow and the katabatic winds increasing, snow dunes were forming perpendicular to the direction of the wind -- it was like being at sea! Half a day later, sastrugis developed along the wind direction and snow became hard and compact.

With the amount of fresh snow and the katabatic winds increasing, snow dunes were forming perpendicular to the direction of the wind — it was like being at sea! Half a day later, sastrugis developed along the wind direction and snow became hard and compact.

A snow drift blocking the door of the kitchen tent.

A snow drift blocking the door of the kitchen tent.

The IMAU intelligent Weather Station, installed in its snow pit before we refilled it.

The IMAU intelligent Weather Station, installed in its snow pit before we refilled it.

Ludo inside a 2-m-deep pit dug with the hope to repair a broken pilot pipe for installing a pressure transducer in the aquifer.

Ludo inside a 2-m-deep pit dug with the hope to repair a broken pilot pipe for installing a pressure transducer in the aquifer.

Ludo, inside a larger 2-meter-deep pit dug after dinner with easterly winds increasing as another coastal storm was coming bringing more snow. Our rationale was that the sooner we dug, the less snow we’d have to remove.

Ludo, inside a larger 2-meter-deep pit dug after dinner with easterly winds increasing as another coastal storm was coming bringing more snow. Our rationale was that the sooner we dug, the less snow we’d have to remove.

Two hours before being pulled out from the field, Clem was dragging the 200 MHz radar, and carrying a GPS unit.

Two hours before being pulled out from the field, Clem was dragging the 200 MHz radar, and carrying a GPS unit.

(Left) Snow accumulated on our tent entrance overnight. We monitored it carefully every half hours from 2 am to the late evening. We took care of it a couple of times! (Middle) Clem calling the weather service to find out what wind speeds would hit us during the night. (Right) Our last saucisson, hanging over the snow/water pot.

(Left) Snow accumulated on our tent entrance overnight. We monitored it carefully every half hours from 2 am to the late evening. We took care of it a couple of times! (Middle) Clem calling the weather service to find out what wind speeds would hit us during the night. (Right) Our last saucisson, hanging over the snow/water pot.

Clem uses an evening break in the weather to drag a low-frequency radar in the fresh snow deposited in the previous hours.

Clem uses an evening break in the weather to drag a low-frequency radar in the fresh snow deposited in the previous hours.

Clem dragging the 400 MHz radar over the sastrugis, a challenging surface to work with.

Clem dragging the 400 MHz radar over the sastrugis, a challenging surface to work with.

Weather was clement enough with Clément to allow him for a pit stop during our half-marathon radar day around camp.

Weather was clement enough with Clément to allow him for a pit stop during our half-marathon radar day around camp.

A new day, different weather, and another attempt to collect more radar data. Since we aim at collecting surface-based radar data, not airborne radar data, we quickly had to stop because the wind would make the radar system take off with every other gust.

A new day, different weather, and another attempt to collect more radar data. Since we aimed at collecting surface-based radar data, not airborne radar data, we quickly had to stop because the wind would make the radar system take off with every other gust.

Pictures taken just one hour apart. In the top one, we were setting up a radar system. In the bottom one, we were actively wrapping it due to sudden katabatic winds that picked up in less than 10 minutes.

Pictures taken just one hour apart. In the top one, we were setting up a radar system. In the bottom one, we were actively wrapping it due to sudden katabatic winds that picked up in less than 10 minutes.

Indoor activities while the winds prevented us from working. (Left) Playing domino with mitts in a shaking tent, unforgettable times! (Right) Good food to keep us happy. Merci maman for thinking about us before leaving home.

Indoor activities while the winds prevented us from working. (Left) Playing domino with mitts in a shaking tent, unforgettable times! (Right) Good food to keep us happy. Merci maman for thinking about us before leaving home.

Our flight back had already been canceled twice. It turned out that this was our last evening at camp. We had a total of two pretty sunsets: one on the first day and the second 12 days later, on our last evening.

Our flight back had already been canceled twice. It turned out that this was our last evening at camp. We had a total of two pretty sunsets: one on the first day and the second 12 days later, on our last evening.

Our bags, ready for a surprise pull-out flight! Happy Easter!

Our bags, ready for a surprise pull-out flight! Happy Easter!

A great moment: the landing of the B-212. We were being pulled out!

A great moment: the landing of the B-212. We were being pulled out!

The crew and Ludo finish up loading the B-212.

The crew and Ludo finish up loading the B-212.

Last view of the ice sheet and glaciers.

Last view of the ice sheet and glaciers.

Forty minutes after leaving our camp, we see signs of life: a view of Tasiilaq (top) and Kulusuk (bottom), minutes before landing.

Forty minutes after leaving our camp, we see signs of life: a view of Tasiilaq (top) and Kulusuk (bottom), minutes before landing.

We’d like to finish with this quote from the French explorer Jean-Baptiste Charcot, who led the second French expedition in Antarctica around 1910:

“D’où vient l’étrange attirance de ces régions polaires, si puissantes, si tenaces, qu’après en être revenu ou oublie les fatigues, morales et physiques, pour ne songer qu’à retourner vers elles? D’où vient le charme inouï de ces contrées pourtant désertes et terrifiantes?” (“Where does the strange attraction of the polar regions come from, so powerful, so stubborn, that after returning from them we forget the fatigue, moral and physical, only to think of returning there? Where does the incredible charm of these lands come from, however deserted and terrifying?”) Jean-Baptiste Charcot, Le Pourquoi Pas?

Notes from the Field