Thursday, December 25, 2014

Merry Christmas from the bottom of the world


We flew into Williams Field and took the ski road (pictured)
into McMurdo.  Pegasus is another airfield.  The shelf break,
where the ice shelf ends, can be seen as a ridge above.  The
sea ice is to the left of the shelf break and surrounds Ross Island,
on which McMurdo is located, until later this summer.
We arrived in McMurdo at six in the evening on Christmas Eve.  White light was reflected in all directions as we got off the plane.  It was only lightly snowing but you couldn't tell ground from sky. The effect was lost once we got into town and had brown dirt under our feet.

We went directly to an orientation at the National Science Foundation (NSF) chalet.  The NSF is the governmental agency that funds the scientific research that Americans do in Antarctica.  The station manager, Terry Melton, spoke with us about rules and regulations pertaining to the US Antarctic Program under the Antarctic Treaty System, as well as best practices that they have developed to stay safe, reduce waste, and protect the environment.  I then received the binder which is to be my bible while I'm here (see below) from Julie Raine, our implementer and employee of the Antarctic Support Contract.

From there I went to pick up my laundry, which is issued in big blue bags to match the big blue building which is home to the short-term residents (that's me!), the galley (cafeteria), general store, craft room, weights room - the list goes on.  I made several trips to and from the blue building as I went to retrieve my luggage, overheating in my thick red parka.  I was assigned an interior room, the down-side and up-side of which is there is no natural lighting.  I always prefer a window, even though it means that you need to wear an eye mask to achieve darkness when it is time to sleep.   I have two roommates, both of whom have been waiting for ten days to get out to their field camp, WAIS Divide, located where the West Antarctic Ice Sheet (WAIS) divides into roughly north-flowing ice streams and south-flowing ice streams.




















The Vehicle Maintenance Facility throws a Christmas party every year.  They empty out the warehouse and decorate it with lots of backdrops, including cutouts of tin soldiers and reindeer, seating for both Santa and the Grinch, and blow-up penguins and, puzzling enough, a gargoyle too.

A choir sings carols at the VMF Christmas party
Carolyn (head) and Diana (bottom) 



A little incongruous

 Christmas dinner is quite a production - served in four shifts which you must sign up for beforehand.  People started lining up 45 minutes before their shift, and I joined them to help reserve tables for our WISSARD group.  The meal was fantastic, and drew a standing ovation.  Here's a few of the things that ended up on my plates:
Potato pancakes with spiced applesauce
Shrimp and clams
Spinach artichoke dip
Baked gouda
Blue cheese ball
Almond carrots
Butternut squash with candied walnuts
White chocolate cheesecake
Grasshopper pie
Our meal schedule for the next few days, posted on the USAP intranet
I'm thinking of all of my family and friends today and hoping that you all have a wonderful holiday season!  Thanks for all of your loving support throughout the year.

Wednesday, December 24, 2014

This WISSARD flies south

After months of preparations, I am headed south for another season of drilling with the WISSARD project!  For those of you that didn't follow my blog last year, I am Carolyn, a graduate student at University of California, Santa Cruz (henceforth, UCSC), who is studying the dynamics of large ice sheets.  You can read about the WISSARD project more generally here and about me here.  The goal of this season is to drill into the grounding zone of the Whillans Ice Stream, where the ice goes afloat over sea water.  As we have done in the past two years, we will be utilizing hot water drilling technology, essentially melting a rather narrow hole through the ice.  We will be assessing ice stream stability, that is, the ice's response to internal changes and oceanographic changes.  A suite of borehole instruments and water and sediment samples will provide key observations to make this assessment.  Earth scientists have been using ice sheet models coupled to climate models to assess how ice will respond to climate changes.  Our observations at the ice-ocean interface will help the community improve upon these models by providing a point for comparison.   Here's some of what we've been up to lately to get ready:

July and August:
Dan Sampson and Eli Morris, UCSC engineers, and Slawek Tulaczyk and I, UCSC scientists, work on the assembly of instrument strings to lower down the borehole.

September:
Robin Bolsey, the engineer who designed our sediment corer, visits UCSC to train me on how to use it in the field.  We send off our first shipment of equipment by boat from Port Hueneme, CA.


October: 
We send off our second shipment by air from Port Hueneme.  This contains the datalogger and satellite transmitter that our engineers have been working to test and program as well as the rest of our equipment.


November:
Andy Fisher shows Slawek and I how to use the geothermal probe that he has worked to design and implement.  The WISSARD team deployed the geothermal probe last year and got the first measurement of geothermal heat flux on the Antarctic continent.  We are hoping to get the second measurement this year.

A traverse team leaves McMurdo Station for our remote field site.  They travel for 11 days across the ice on tractors pulling equipment and fuel.  They will prepare our site for drilling, moving supplies and lab units from the Subglacial Lake Whillans drill site of two years prior to our new drill site at the grounding zone.

I also celebrate the Thanksgiving holiday with my family, as I will be spending Christmas in Antarctica.  We even bake Christmas cookies and open presents almost a whole month early.

December:
I attend the first couple days of the American Geophysical Union fall meeting, a conference attended by nearly 24,000 Earth scientists, educators and policy makers.  I got a chance to chat with some really fantastic scientists before heading home to do my final packing.  Here's what I ended up bringing:
1 suitcase of sensitive instruments and a toughbook computer
1 duffel of clothes, boots, sneakers, toiletries, and a small Christmas gift
1 duffel with camping gear that I hope to use in New Zealand following my fieldwork
1 backpack with books, laptop, movies, and snacks

On December 19 I boarded a plane in San Jose.  Two days, two novels, much waiting, and many fits of sleep later, I arrived in Christchurch, New Zealand.  I wasn't able to see much improvement in the downtown area from last year to now.  There are still so many boarded-up and fenced-off buildings as well as empty gravel lots.  The street art, however, brings some color and cheerfulness to an otherwise grim and near-apocalyptic cityscape.

One of my favorite murals in the city - the penguins melt as the ice does
About a dozen of us headed down to the ice went to get our cold weather gear from the Clothing Distribution Center (see my post from last year).  I was pleased to find that several of my items were new - the fleece still has that lovely texture it loses on its first wash.

Our flight was delayed by a day so some of the WISSARD team members and I made our way over the hills to Lyttleton, Christchurch's port town.  We took the scenic route over the hill on the way there and the much shorter tunnel pass (highway 74) on the way back.


Christmas eve: After a brief delay to make a repair, we take off on the Mighty Hercules (LC-130).  With a brisk wind at our back, we're optimistic that we'll have a smooth flight.





Sunday, February 23, 2014

Goodbye, Antarctica

23 February 2013
Santa Cruz, California

Well, our lab group is now all back in California.  Things got a bit hectic back in McMurdo but I will try to do a quick recap of our exit from Antarctica.  After drilling the final hole, we traversed back to CReSIS camp, where they have a groomed runway.  Because the plane to take us back to McMurdo was rather small, as you can see below, we kept some of our gear out in the field to be used next year when we return (fingers crossed!).
 
The Basler and
(back row) Grace, Dan, Slawek, Susan, Julie
(front row) Me, Neil, Matt

The views from the plane were stunning.


When we got back to McMurdo the sea ice had largely disappeared. One felt so much more in touch with the world with the ocean lapping at the shores of the town.  The vessel, which comes once at the end of the summer to resupply the station for the winter, arrived and 100 people came down to help with the off-loading and on-loading of the ship.  A good portion of the station was also restricted-access so that the process would be most efficient.


Adelie penguin








The best part about the open water was access to wildlife.  For the past five weeks we saw one bird, but now we could see penguins, seals and orca whales. 
The water looks so blue because the floor is ice

Weddell seal

















We were able to wrap things up in McMurdo fairly quickly.  Unfortunately we weren't able to get Neil on our flight out of the field and then some weather delays pushed his flight back to a week after ours.  Both Neil and I took two weeks in New Zealand to re-acclimate.  What a contrast with the white desert it was.  We were surprised to encounter almost as much isolation on the hiking trails as we did in Antarctica. 


Well, now it's back to sitting in front of a computer screen.  What diverse experiences grad school has offered so far.  All in the name of science... and because we find it fun.

Thursday, January 30, 2014

Loneliest gas station

Refueling at what Neil likes to call
"The loneliest gas station in the world"

Saturday, January 25, 2014

continuous GPS unit and Matt

It was a windy day servicing seismic instruments. Here's Grace and I
hunkering behind a skidoo, snow blowing around us.

Four boreholes drilled successfully

26 January 2014
Site 2b, Whillans Ice Stream

When we first arrived to the grounding zone, the light on the mountains was gorgeous.
Site 2A location, Bush Mts in the background
Slawek with the seispod at the bottom of the cable.
Back row: Grace, Slawek
Middle row: Susan, Dan, Neil, Matt
Front: Me

This afternoon we finished deploying instruments in our fourth and last borehole. These last two boreholes were located near the grounding line of the Whillans Ice Stream.

We have been doing maintenance on a GPS array
near here that has been collecting data for the past couple years. We were excited to find that several of them have been running throughout the entire year, being powered by solar energy in the summer and wind energy in the winter. Today we will put in a few more GPS units. Tomorrow is a packing day and then we head back to the now-almost-abandoned CReSIS camp for our flight out of the field. We are really happy with what we have been able to accomplish this season!

Sunday, January 19, 2014

2 holes drilled

19 January 2014
Site 1B, Whillans Ice Stream, Antarctica

The traverse is off!

We did have flat light for our journey out to the first borehole location but the journey went fairly smoothly with a few adjustments to our sled loads.

A mid-journey break
The scientists on skidoos and the drillers on the traverse pulled up to the location which would be the site of our first borehole. It was marked by a seismic station, on the surface a box and solar panel, which looked miniscule by comparison with the large tractors and the wide ruts they made in the soft snow. The drillers got right to work and by lunchtime the next day the hole was finished. We found out the approximate thickness of the ice from the CReSIS team based on the raw data from this year's survey so that we could avoid entering the subglacial environment, not being equipped with clean access technology as we were last year.

Drill Site 1
Water hose rigged for drilling



The depth of this hole was 690 meters and took about 12 hours to drill. The drill uses hot water to melt the ice. At its maximum speed, it melts the hole at 1 meters per minute and exits the hole at a rate of 2 meters per minute, also pumping hot water to keep it open. The hole ends up 0.8 meters across.






Tiltmeter above seispod about to go down the hole.
My job for part of the deployment was to
ziptie the cables together as we put them
down the hole.
Then us scientists set up reels of cables to send our equipment down the hole. This equipment includes small seismic sensors, and distributed tilt meters. These all went down the hole simultaneously, taping the cables together as we went. All of our equipment was in by dinner and so far everything is running as it should. We are all happy with this success.

Bulldozer pushing snow into the hot water tank.
We repeated the process at the second hole, which is located a little more than a kilometer from the first hole. At this distance, we think that both sensors will be able to detect some of the same seismic events. Both of these boreholes lie within the zone of high seismic noise we detected over the course of last year, indicating sticky motion of the ice over its bed. This time, we sent down distributed temperature sensors in addition to the instruments used at the last hole. When we had deployed about 300 meters of cable some bit of the cable got caught on the wall of the hole. We tried raising and lowering the cable a few meters to get past but we soon found that the cable was frozen at that point, for it took a lot of force to turn the reel. We would have liked to get closer to the bed, but we still expect to get a better seismic signal of the stick-slip motion at half the ice thickness than at the surface.

Me with the GPS receiver.


Today Slawek and I took static GPS measurements in a line perpendicular to
the flow of the Whillans Ice Stream with subglacial Lake 7 at one end and stretching across the seismic array within which we have been drilling. We set flags in the locations of our measurements so we can return next year and see how far the ice has moved. We expect we might see the sticky spot slowing down ice flow.




Tomorrow we travel forty kilometers to the grounding zone, where we will drill two more holes. I'm excited to go to a new location for the last 11 days of the project.

Monday, January 13, 2014

Field update: 6-man operation

14 January 2013
CReSIS camp, Antarctica

A belated happy new year to you all! On New Year's Day we set out from CReSIS camp toward the Transantarctic Mountains. It was slow going with all of our camp gear and some of our science gear, and we arrived late in the evening to our chosen patch of ice.




 From the cleanest, whitest slate we began constructing our town, equipped with a kitchen tent (yellow above), science tent (red and blue above), bathroom (read: hole with a tent overhead, orange above), mountain tents for sleeping, and a few pee flags. Most of our time at camp is spent in the kitchen tent, where we spend a lot of time melting drinking water from snow, eating and talking. The floor in the middle of the tent is compacting and melting at a greater rate than the rest, and chairs and
tables are starting to list toward the middle.

Just enough room for my sleeping bag
and luggage.
A bit of drifting around my mountain tent
 The snow beneath my tent that is not insulated by my sleeping pads has also melted significantly - those mountain tents get hot enough to make a fleece bag liner sufficient at night. The weather has been quite nice, most days between -4 and -2 degrees C and sunny. The wind comes in pretty steadily from the Ross Sea and one day picked up enough to make huge drifts around camp. I find the undulating topography behind our line of snowmobiles rather fun; the spacing is perfect to leap from one drift to the next.

We have now been out in the field two weeks. We have visited the seismometers we left on the ice last year and collected the data. The data does show the slip events that we hope to study further and has some interesting patterns associated with different stages of these slip events. Grace is using this data to design a distribution of seismometers that will allow us to constrain the geometry of the sticky spot at the ice-bed interface. We are installing seismometers in these new locations. The sensor itself is buried several feet below the surface to get better coupling to the snow and to increase the odds that it will remain level through the year. After placing the sensor we test the reception on three
channels corresponding to three axes oriented vertically, north-south and east-west by jumping up and down. Neil, Grace and Doug are also using active seismics, creating a wave by hitting the ice with a mallet, targeting the regions with a lot of seismic noise. The reflection from the bed should give us information about the characteristics of the bed surface. This season the CReSIS team collected airborne radar data on the Whillans Ice Stream that will show internal ice layers and the ice-bed interface when it is processed.

We took a trip out to Subglacial Lake Mercer, another one of the lakes in this regional hydrologic system that has been active in the past decade. GPS stations have been collecting data there for the past two years. Matt, Slawek and I travelled there to service the stations, installing new turbines on one of them and removing another (see photo). The one we moved will help us calibrate the GPS measurements we will be taking at locations in a grid once this season and once next season to measure a year of movement over the sticky spots and at the grounding zone.

The traverse has arrived at CReSIS camp with our equipment, and they will be heading straight to the site of the first borehole we will drill this season. We traveled to CReSIS camp to meet the traverse and welcome Susan Schwartz and Dan Sampson from UC Santa Cruz and the drillers, who arrived
by plane. We are very excited to start this new phase of the project. We said good-bye to Doug Bloomquist, who has been a huge help in getting the seismometers installed and running. While we are here, Slawek collected distributed temperature measurements down the hole from the surface to
Subglacial Lake Whillans. The sensor string was lowered into the hole last season and is now completely frozen into the ice. Today we leave by skidoos with Susan and Dan for our camp, which will pack up and move closer to the drill site. This morning I awoke to a fog that wipes out
the horizon completely. I hope we get better visibility soon so that our newcomers can enjoy a view of the mountains on our journey. Here's to smooth travels! Off to loading sleds -