We have a storm day here on Memorial Day, so I have some time to share with you some of my thoughts about the expedition so far.
|Greetings from Camp Dartmouth!|
Climate Change Evidence is Everywhere
Our overall research objectives here are to understand how climate change is affecting the balance of snowfall and surface melting on the Greenland ice sheet - and ultimately what that means for future sea-level rise. 2015 SHATTERED the record for highest global average temperature, and 2016 is setting a pace to break that record. During this expedition, it's impossible to miss the impact that climate change is already having here.
We can start in the weeks before we even got on the plane in Scotia, NY. The Greenland science community was buzzing on April 11 as surface temperatures over much of the Greenland ice sheet went above freezing and we had our earliest melt event on record. To put it into context, we wanted to avoid surface melting as much as possible on this trip (bad for radar data, ice coring, and snow camping), which is why we chose to be here in late April and May, into early June. Usually we don't see surface melting at our locations until mid June or later. So to see in EARLY APRIL (!) was stunning.
The culprit was a big loop in the Jet Stream called an Omega Blocking pattern. This brings warm air from the south up to Greenland, but moves cold air down over areas to the east and west of Greenland like to the USA East Coast. These blocking patterns tend to persist for weeks at a time, and it was still in place when we arrived in Kanger on April 25 when it was in the 60's or warmer for that first week. Kanger is usually still feet-deep in snow in late April - but it was snow-free and brown this year (like New Hampshire was all winter!). The rivers draining the ice sheet were flowing much faster than normal, and the local hunters were unable to get to their normal sites because the sea ice was melted too far back.
|t-shirt weather in Kangerlussuaq, Greenland...|
Meanwhile, it was snowing in Hanover, NH!! Yes, it was 30+ degrees warmer in Greenland than in Hanover in late April. Gabe was wearing shorts and tee-shirts in Kanger while our families back home dealt with a late-season snow storm. The same type of blocking pattern produced the famous melting event in July 2012 that caused surface melting even at Summit, Greenland.
The question is - what causes these blocking patterns? And are they related to climate change?
This is an area of active research and some debate in the climate science community. It's also a particularly important question because it represents the interface between climate change and weather change. Of course, people experience weather changes, so it strongly influences people's perception of climate change. A research group out of Rutgers led by Dr. Jennifer Francis has shown that declining arctic sea ice and snow cover in Siberia (both definitely from climate change) help to contribute to these blocking events. The jet stream responds to temperature gradients from the equator to the pole. As the arctic warms faster than the mid latitudes with climate change (due to things like melting sea ice and decreasing snow cover!), the jet stream tends to slow down, and as it does, you can get more of these big jet stream loops than cause blocking highs. So while I'd personally say that the science on this point is not settled, there is good evidence that these blocking patterns happen more frequently with climate change.
|Omega Blocking in Greenland leading to melt events|
(SIDE NOTE: The reason why Hurricane Sandy veered west into New Jersey - an EXTREMELY rare course for a hurricane to take - was due to one of these blocking patterns).
In the ice cores we are collecting, we can see that these surface melting events have become more and more common in recent years. The ice that forms when snow melts and then refreezes looks very different than the ice that forms when snow slowly compacts over time without melting. So we can distinctly see summer melt events in the ice cores as we collect them. 2012 stands out as a huge melt year in our observations here - that was a really warm summer in Greenland including the previous July Omega Block melt event. It's a solid meter of refrozen meltwater in the ice cores, and it stands out as a very dark reflector in our radar data. As the cores go deeper and deeper, further back in time, we see fewer and thinner refrozen meltwater layers. This is consistent with our records from Greenland weather stations showing warming temperatures since the 1950s. In a paper we published last year, we showed that if you remove the temperature signal caused by natural climate cycles (including the North Atlantic Oscillation and Atlantic Multidecadal Oscillation), there has been a steady warming in NW Greenland of 2.9oF since 1952. That's about three times the global average warming rate.
It's turned much colder here for the past week, which has been nice for our work. But our custom weather forecast from GreenTrACS project PI Dr. Sean Birkel (at UMaine) shows more possible surface melting on Thursday and Friday. I have a feeling that this summer is going to be like the summer of 2012 - record low sea ice, low snow cover, and frequent melt events in the Arctic. 2015 was such a hugely warm year, all that heat in the atmosphere is not just going away. Stay tuned.
A Science Machine
The night before we flew from Kanger to Raven/Dye-2, Gabe posed the question at dinner: "What are you most looking forward to?"
My response: "I'm looking forward to 5 days from now when we have things figured out, everything is working, and we're dialed in".
5 days was a little on the optimistic side. It took more like 10 days before I'd say we were fully dialed in - a science machine. In those 10 days we learned:
- How our suite of scientific instruments can best be hauled across the ice sheet to get the best data. This is no small task. The power requirements alone for the 4 independent radar systems are challenging, plus the 7 (yes, that's 7) different GPS's we have running (which doesn't include the handheld Garmin GPSs we use to navigate the snow machines). And then there's the laser. Yes, we're dragging a laser across the ice sheet (cue Dr. Evil). Each instrument 'likes' to collect data at different speeds, at different heights above the ice, at different time intervals, and has different science objectives. We now have a 'science sled' that works well for us almost all the time.
- How to best haul 55-gallon drums of gasoline from site to site. It's hard to do much with a snow machine without gasoline. During the first traverse day we punctured 3 of the 4 drums of gasoline we had at that time! This was a HUGE problem!! They were slow leaks - although we still ended up bathed in gasoline - and a little bubble gum helped to stem the flow until we got new empty drums to transfer the fuel into (thanks for the tip, MacFerrin!).
We approached the problem like scientists. After transferring the fuel from the punctured drums to new drums, we had some punctured, empty, useless drums to experiment with. So we tried all these different possible strategies and after each new attempt, drove the sled around camp at high speed (thanks Gabe!) to see how much the drum moved and dented. After several hours of this, we found the ideal (we think) solution. So how do you best haul 55 gallon-drums of gasoline across an ice sheet? Starting with a wide siglin sled, put down two tarps (padding), then a sheet of plywood (doesn't slip), then two ridgerest foam sleeping pads, then the drum on its side across the width of the sled on the pads, with two cargo straps crossing the drum diagonally (making an X) to secure it in place. Between the drum and cargo straps are another 2 foam sleeping pads, and then a heavy canvas tarp to prevent the ratchet on the straps from rubbing through the pads down the drum (which would puncture the drum). The cargo strap hooks need to be looped through the sled tie-downs and hooked back on themselves, or hooked to a metal caribiner (so they don't rub through and break the tie-downs), with all hooks facing away from the drum (again, that puncture thing). And voila - you have a safe and reliable way to move fuel around the ice sheet. Just in case you were wondering.
|The ideal drum tie-down|
- We also learned in these 10 days what our schedule would be at each camp/science site. It's important to develop a rhythm of day-to-day life so that everyone knows what is expected of them and what is possible in these conditions. How far can we really go on a radar 'spur' to the east or west in a day? How long does it take us to drill a 30 m ice core? How long does it take to setup and breakdown camp? (more on that below). So our ideal schedule is:
Day 2: Drill ice core and radar spur to the west
Day 3: Cache run to next site, and radar spur to the east, and camp radar survey.
Day 4: Camp move
This ideal schedule only worked out once - at Site 3. Throw in storm days when we can't work, equipment malfunctions, etc, and we usually add another 1-2 days to each site. But we found our rhythm and that's what's most important.
- Related to the schedule was learning what everyoneís roles would be - not just for the science, but for the day-to-day camp activities as well. Who would take responsibility for each instrument? Who would backup data each night? Who is a good cook (Thomas)? Who's not (no need to shame here)? Who's good at building the bathroom (Forrest)? Who has the best skills with small electronic devices (Gabe)? This was all part of becoming a well-oiled science machine.
|Chef Thomas with MegaSoup2.0|
A Typical Camp Move Day
Our moves from one camp to the next are some of our longest and most challenging days. Here's what they are like:
7ish: Wake up. Start packing up personal gear in tent. Turn on generator to top up science instrument batteries.
7:30: Daily check in with our CPS logistics team in Kangerlussuaq
8:00: All personal gear packed and personal tents empty. Breakfast.
9:00: Gabe, Forrest and Erich start breaking down personal tents and building sleds. Thomas and Tate prepare the radars and science sleds for the day's data collection between campsites.
10:30ish: Start breaking down the kitchen and science tents and continue building sleds.
Noonish: Tate and Thomas start slowly (~10 kph) traversing to the next camp, collecting data the whole way. Erich, Forrest and Gabe continue building sleds and finishing camp breakdown. Break down the bathroom tent.
1:30ish: Gabe, Forrest and Erich are done - have some lunch.
2ish: Erich, Gabe and Forrest start traversing to next camp at ~25 kph.
3ish: Forrest, Gabe and Erich pass Thomas and Tate on the 'road' and check in with them.
5:00ish: Forest, Gabe and Erich arrive at new camp. Start by padding down the tent platforms by driving back and forth with loaded sleds in an east-west orientation. The strongest winds come from the south, so we orient camp in a roughly east-west line to prevent one tent from causing snowdrifts on another.
5:15: Setup kitchen Arctic Oven tent. We can have this fully setup, with everything back to its place inside, in about 30 minutes.
5:45: Setup science Arctic Oven tent. Again, everything back in its place in 30 minutes.
6:15: Erich and Gabe setup the 4 personal tents (Forrest prefers to sleep in the Pod so no personal tent). Forrest sets up the bathroom tent. Each personal tent takes about 10 minutes to put up and fully stake out. We've now setup and broken down these Mountain Hardwear Trango3 tents 44 times. We're getting good at it.
7:00: Erich and Gabe setup cots and personal gear in each tent, dig out boot bays at the entrances, and berm the personal tents with snow. Tate and Thomas check in via sat phone and give their ETA - usually around 9 pm. Forrest starts making dinner.
8:00: Gabe, Erich and Forrest gather in the kitchen tent and start eating dinner.
9:00: Thomas and Tate arrive - usually very cold. Snow machines are fueled and oiled, science instruments turned off, generator turned on to recharge batteries, and they eat dinner.
10:00: Data backup and eventually collapse in bed.
|Camp all set up|
What is amazing is how each camp feels the same. Everything is in roughly the same place at each site, and in the same place inside each tent. And the scenery doesn't change (flat & white). So itís like groundhog day. It must be particularly odd for Thomas and Tate to leave one camp, drive all day, and then seemingly arrive at the same camp that night.
|Tate with the science sled on a late arrival...|
A Frozen Ocean
It's amazing to me how snowmobiling across an ice sheet feels so similar to power boating across the open ocean. I did my Master's degree research in New Zealand out on a research vessel studying underwater canyons far at sea - so I have some experience doing both now.
It's flat as far as you can see in every direction, just like being out at sea. The winds makes sastrugi - waves of snow - that feel just like waves on the sea. There are rough days and smooth days, related to wind strength and direction. Whereas ocean waves form in minutes to hours and move in seconds, sastrugi form in hours to days and move just as slowly. The sound and smell of the snowmobile engines even evoke memories from New Zealand for me. In both situations, you are utterly out of place as a human. Get rid of the boat or snow machine and tents, and you are not long for the world. In both, you occasionally see some wildlife. The other day we had a seagull fly overhead and the analogy was complete. Of course, the similarities make sense: they are both just water in either solid or liquid form.
|Forrest and Gabe holding the moon...|
A Note About Food: and Pop Tarts (arguably also a food)
Central to every glacier expedition is the food. I learned long ago never to let undergrad or grad students plan and buy the food without close supervision (have you ever looked into a grad student's, or worse - undergrad student's - refrigerator? Don't). So I have taken on the role of food planning and purchasing for most of my recent expeditions, including this one.
The food needs change for every expedition. In Denali, we have to haul much of the food on our backs, so weight is a strong consideration. And in Denali, the lengths of our expeditions are difficult to predict due to weather, so it's hard to correctly plan food quantities. Here, we are hauling around 6,000 pounds of equipment by snow machine, so weight is NOT a concern. And we knew when our flights to and from Greenland were - we HAVE to make those flights - so we knew our duration.
So for my expedition food planning, I've developed a very detailed spreadsheet with every food item and the amount one needs per person-day, taking into consideration personal preference of group members. For example, we have 4 coffee connoisseurs on this expedition, and somehow need 4 separate coffee pots - I suppose just in case three of them break (can you tell that I'm not one of the 4?). As another example, some people like canned fish, others really don't. You get the idea.
We have 200 person-days on this expedition, and so I planned on about 275 person-days of food to allow us some flexibility of choice (again, since weight wasn't an issue). That comes to about $3,000 worth of food, which took three separate shopping trips to BJs, Hannafords and the Hanover COOP (in declining order of cost) to procure. So we are NOT going to run out of food. Although we ARE going to run out of CERTAIN foods.
Pop tarts come to mind.
The way I make the food shopping list is a few weeks before the trip, we have a conference call with everyone and we go down the list line by line: "OK breakfast. How many meals per week will each person want cereal (and which kind?)? Oatmeal? Cream of wheat? Granola? Pop tarts?..."
And here is the thing: if people don't speak up, then I can't do my job properly. Every year, with every expedition, the typical response on this phone call is: "I'm easy - I'll eat anything."
This is both incredibly unhelpful and a bold-faced lie. I understand that people are just trying to be accommodating, but it makes food planning very difficult.
The truth is even if someone WILL eat anything, everyone WANTS to eat some things more than others - i.e., we all have preferences. So if you have a group of 'easy' people, what inevitably happens is that everyone chooses their preferred food first, that food disappears, and everyone is stuck eating food they will tolerate but not really like.
This is the situation I'm always trying to avoid. Food is central to both good health and good morale. Anyone can eat anything for a few days or a week. But we're here for 6 weeks - we need good food to stay healthy and happy. I learned a lot about this from my friend, ice core drilling extraordinaire, field food gourmand, and arctic field expert Mike Wasczkiewicz.
So back to the Pop Tarts. When we got to Pop Tarts on the list during the phone call, the response was luke-warm at best. "Sure, I'll have one every now and then" seemed to be the common response. So I bought 50 person-meals of pop tarts, or 10 person-meals each, or one breakfast every 4 days per person. That comes to 100 packs of pop tarts with 2 per pack (so 4 individual tarts per person-breakfast).
Turns out that we are all closet pop tart addicts.
What happened was all-too predictable. As the pop tart supply started to dwindle, there was a rush on the remaining stock. There was some hoarding (I suspect), some hiding (I did bury a pack of 24 deep in the breakfast box - but only for the good of the whole team. I didn't tap into it. I swear), and a lot of nervous mornings. Shifting eyes as our minds swirled with accusations: "Is he having ANOTHER pop tart? Didn't he have one yesterday? Wait, is he having one for LUNCH?!?!" And so on.
So what happened? How did this go so wrong with such a simple, delicious, food-like product?
My guess is that the problem comes down to a difference between what one eats in 'the field', and what one eats at home. I don't think I've ever eaten a pop tart at home. Honestly. But here, I can't get enough of them. And here's the odd thing - it's not like I'll eat them at home when I get back in a couple weeks. I will go back to never eating pop tarts - except in 'the field'. This is a phenomenon that my wife has noticed over the years. She'll hear about my trips, and our meals on those trips, and note: "you never eat that at home!" I realize now that this is not unique to me.
So what is one to do? I think I need a multiplier for each item on my list to account for the field-food effect. Some foods will have a multiplier of <1. For example, Honey is a real pain-in-the-rear to deal with on a glacier because it doesn't flow. So maybe Honey has a multiplier of 0.25, meaning that one has 1/4 as much honey on a glacier as at home. (I note that we have not actually opened up a single honey jar yet - and we're on person-day 150. So maybe the multiplier should be 0.1). Peanut butter is similar - it's really hard to spread frozen peanut better; give it a multiplier of 0.4. Other foods will have a multiplier >1, like pop tarts: maybe a multiplier of 2 or 2.5. That would be about right for this group.
Other things can also go wrong with the food. For example, we've managed to lose one of our two 5-lb bags of pancake mix. I usually cook pancakes and bacon for the group on storm-day mornings. It keeps morale up, and pancakes take a while, and we have time to kill on storm days. But not this morning. No more pancakes. I KNOW I bought 2 packs of mix. It's on the list, and I remember seeing two. But one has disappeared. Maybe someone is using it as a pillow? Maybe it got left and buried in the snow when we re-organized food boxes at Camp 2? Or maybe it's out there in a food box somewhere, and we just can't find it under all that peanut butter and honey. Who knows? But it was plain old granola for breakfast this morning. Such is the hard life on the glacier.
|Bacon-wrapped sausages: An Ice-sheet Memorial Day special!|