Ice crystal halos

We saw several beautiful displays of halos in the Allan Hills. Halos form when ice crystals in the atmosphere (typically in cirrus clouds) scatter the light into different angles.

New snow leads to blowing snow

A couple days into our stay in the Allan Hills, it started to snow. In total, it snowed about a foot over a day. At first, the snow was beautiful, but then the wind picked up to 25 knots and it started to blow around. We were stuck in the tents for three days due to poor visibility from the blowing snow. 

New snow at our campsite

Blowing snow

Blowing snow

When the wind finally subsided, all the new snow had blown away. Similar to patterns that you would see in a desert (we are in fact in a desert!), the wind leaves dunes, wind scoops, and ripples on the surface.

Wind sculpting the snow surface

Wind ripples on the ice surface

The blowing snow left us with some nice big (2-3 ft) snow banks around our tents. 

Finding old ice in the Allan Hills

What exactly were we doing in the Allan Hills?

Back in 2010, a group of scientists drilled an ice core in the Main Ice Field of the Allan Hills. They dated the ice to one million years old. That's really old ice! Most of our current ice core records, such as the recently-drilled core at the West Antarctic Ice Divide, date back only 100,000 years. The ice in the Allan Hills provides a unique opportunity to explore our climate history farther back in time.

Unfortunately, the million-year-old ice was found by itself. The ice directly above it was dated to 300,000 years old. That's not a continuous record of climate change, and as a result it's hard to put the observations that we make about the million-year-old ice into perspective. So the goal of our project was to trace this old ice back to where it came from and find a good place to drill a continuous, old ice core.

Why is there really old ice in the Allan Hills?

The Allan Hills is a blue ice region. The region is so windy and cold that the snow blows off the ice surface before it can melt or accumulate. As a result, old blue ice is exposed at the surface, hence why we call it a "blue ice region." Furthermore, the Allan Hills are a physical obstacle that the ice must flow over, which brings old ice at depth to the surface. The glacier velocities are so small (less than 10 feet per year) that it takes the ice a long time to move anywhere.

How do we map the old ice if it is below the surface?

Have you ever gotten an ultrasound or an x-ray? We use a similar technique to image the ice, except we use radio waves. We send radio waves down into the ice, and these waves reflect off of ice layers with different densities and/or chemistries. The waves return to the surface, where we record their travel time and phase characteristics. Through this technique, we can trace internal layers in the ice. Some of these layers are ash layers that have been dated, so we have a sense of the age of the ice.

Below is an image of our radar setup. We tow a sled with a transmitting and receiving antenna, with a central frequency of 7 MHz.

Charging the batteries on the wood sled with the receiving antenna and red sled with the transmitting antenna 

Did we find a place to drill a continuous ice core?

We think we did! We found a region upstream of the million-year-old ice where we think we can drill a continuous 1200-m ice core that should date back to at least ~400,000 years. We won't know the actual age of the ice until we drill it. 

Dragging the radar setup across a blue ice area

Finally made it to the Allan Hills

After several bad weather days, we finally made it to the Allan Hills. The Allan Hills are a 45-minute flight from McMurdo across the McMurdo Sound and over the glaciers just north of the Dry Valleys. It took four Twin Otter flights to get all our gear there.

Flying over the Mackay Glacier

Flying over the mountains just before the Allan Hills

The Twin Otter taking off

Once we landed in the "deep field," we were required to set up a tent and make contact with McMurdo before the plane could leave us behind. By the time the two Twin Otters returned with our second load of gear, we had set up two of our four tents, a Scott Tent and the Arctic Oven. Two of our tents were for sleeping, one was for the toilet, and the other was for cooking and science preparations.

The two Twin Otters lining up to unload our gear

more cancelled flights

We're still weather delayed here in McMurdo. I've spent the past few days exploring the area and trying to get some work done.

On Friday, I went up Observation Hill with Michelle, who arrived the middle of last week from South Pole. The views were even more spectacular than the last time I was up there.

Mt. Erebus in all its fiery glory from Ob Hill

Williams Air Field out on the ice shelf

On Saturday, we headed out on the Castle Rock trail. The views were also spectacular.

Mt. Erebus from the Castle Rock Trail

Castle Rock Trail

On Sunday, I had the opportunity to check out the inside of the Discovery Hut, which Scott built during the Discovery Expedition of 1901-1904. The hut was mostly used for storage, but people slept in it at times.

Discovery Hut

another day of cancelled flights

We woke up this morning, brought our McMurdo clothing over to our "cage" for storage, packed a lunch, and waited for the call telling us whether or not we would fly to the Allan Hills today. We found out that our flights were cancelled, again due to weather. Unfortunately, since it is a Saturday and no one works on Sundays, our next possible flight day is Monday, so we will be in McMurdo for the weekend. I plan to get some work done, do some short hikes around the area, and most importantly go to the Forklift Rodeo on Sunday.

flights cancelled

We woke up this morning to find out that our flights would be cancelled for the day due to bad weather in the Allan Hills. Despite the Allan Hills being only about an hour flight away, the weather is completely different from the weather in McMurdo. There is not a cloud in the sky here at McMurdo, but it's apparently very windy in the Allan Hills and unsafe to land and set up our tents. Hopefully we'll get out tomorrow.

field preparations in McMurdo

The last fews days have been a whirlwind. After arriving in McMurdo on Saturday, we had a lazy Sunday because everything was closed. The weather wasn't great and we got a bit of snow, so I mostly used the time to catch up on sleep, go for a very short hike out to Discovery Hut, and check out the town.

View towards the mainland from McMurdo at the beginning of the storm

On Monday we sat through roughly eight hours of orientation and started collecting gear for the field. You fill out forms before arriving requesting some of the gear that you will need in the field, but once in McMurdo you have to collect that gear and order some more. The gear is spread out around town, so you spend a lot of time schlepping gear from its origin to science cargo, where we log all our gear and prepare the gear for shipment into the field. We ended up shipping 5300 lb of gear in 104 boxes (not including our snowmachines). Between various orientations and field preparations, we've had a crazy couple days.



Despite the crazy schedule, I did have the opportunity to run up Observation Hill, which overlooks McMurdo, after the storm had passed. It was great to get a birds-eye view of the area.

View of McMurdo from Observation Hill

View of Scott base, the New Zealand station, from Observation Hill

U.S. Coas Guard Ice Breaker in the sea ice near McMurdo. At the end of each summer season, a cargo ship comes down to resupply McMurdo with fuel and food. The Ice Breaker clears the way for the cargo ship to get to McMurdo.

We are scheduled to fly via Twin Otters to our base camp in the Allan Hills tomorrow. We will need four put-in flights to get all our gear there. We'll go on the first flight with our food and camping gear, and the science equipment will come on the remaining flights. I won't have internet while we are at Allan Hills, so you won't hear from me for about three weeks. I'll make some posts about our fieldwork upon my return to McMurdo.

Made it to McMurdo!

After several hours of delays and an eight hour flight, I'm finally in McMurdo! I won a trivia contest that gave me the privilege of sitting on the flight deck (with the pilots) for the landing on the Ross Ice Shelf. On the final approach, we passed a pod of orcas whales and seals resting on the sea ice. The US Coast Guard's icebreaker was also visible in the pack ice; the icebreaker comes once a year to McMurdo to provide supplies for the winter.

Once arriving in McMurdo, we sat through yet another briefing, grabbed our linens, and picked up our luggage.

Our gear loaded onto a palette in the back of the DC-130

Seating arrangement on the DC-130

My first view of Antarctica!

More Antarctica

Getting off the plane onto the Ross Ice Shelf

Our ride from the "airport" to McMurdo

Looking down on the road out to the airport

A day of cancelled flights

I woke up this morning at 430am to my hotel phone ringing. Our flight to McMurdo had been delayed by four hours. I went back to sleep and woke up several hours later to go for a quick run through the Botanical Gardens. When I returned from my run, I found out that our flight had been cancelled and that we would fly tomorrow instead. Fingers crossed.

With our flight cancelled for the day, we decided to check out the Christchurch Gondola in Lyttelton. The weather was beautiful and views were stunning.

View back towards the beach near Christchurch

Lyttelton

Cold weather gear

After getting to my hotel in Christchurch around 1am yesterday morning, I woke up six hours later to head to the US Antarctica Program headquarters to pick up my cold weather gear. I got my "Big Red" (a very warm down jacket with a fur-lined hood) and a pair of insulated carhartts. I imagine these two items of clothing will be my primary outerwear for the next few weeks. I tried on four different pairs of carhatts before I found a pair that fit just right.

We finished up at headquarters around noon and had the rest of the day to explore Christchurch. We took the opportunity to walk downtown and explore the botanical gardens. As you may know, Christchurch experienced a magnitude 6.3 earthquake in February 2011 that killed 185 people. Roughly 2/3 of those deaths occurred when several buildings collapsed in the heart of the city. At the time of the earthquake, I was living in Wellington and had several friends in Christchurch. I visited Christchurch twice in the year after the earthquake but the city center was still in the "Red Zone" and inaccessible to the public.

Yesterday I had the opportunity to finally see the Red Zone. I had expected most of the construction and restoration to be done by now, but there is clearly still a long ways to go.

Cathedral Square 

Christchurch Cathedral

Bridge of Remembrance

On my way to Antarctica!

To get to Antarctica, I will fly through Christchurch, New Zealand. Right now I am sitting in the Sydney airport waiting to board the plane to Christchurch. It has been over 30 hours since I left Seattle and I have yet to reach New Zealand. 

I had a ten-hour layover in Sydney, so I took the opportunity to leave the airport and head downtown.

Royal Botanical Gardens

Sydney Opera House viewed from beneath the Harbor Bridge

Hopefully my next post will be from Christchurch!