Thursday, February 27, 2014

Uh, turns out that we only arrived here yesterday. Even though yesterday was a long time ago.

After some discussion with Zahra, we've deduced that we only arrived in Eureka yesterday. This took some calculation and puzzling. I logged into my blog account today with a guilty sense of “I didn't even write to say we've arrived! I guess if I just do a few days' of posts, I'll catch up soon”. Well. I don't feel so bad now that I realize we've barely been here for 30 hours.

I'll catch you up anyways. Because we did some stuff.

Breakfast was good this morning! I'm pretty sure Roxanne thinks my breakfast standards are low because I was quite happy to find my way to a delicious bowl of porridge. She probably doesn't know just how much I LIKE good porridge. There were eggs and pancakes and other things too, but porridge is delicious. Plus, you can decorate it with colourful fruit.

Sham is studying water vapour, so we were anxious to get the ultraviolet laser put back together today. Chris was going to help us align things in the sky, so we were at the mercy of his schedule in Halifax. Clear skies are also needed. We had both lined up for today, conveniently. We started in first thing. Sham got the pump chamber in with not too much trouble, but the hoses for the cooling system needed some gaskets replaced. That accomplished, we got the UV laser prepped for alignment and measurements.

I was sort of dreading that moment. Putting hardware back together makes me happy. Aligning cranky laser beams can sometimes make me want to cry. Today, however, alignment went very smoothly. Sham had some good ideas for how we could tell how far out of alignment we were starting, and combining that with the usual procedure helped confirm that we were on the right track. I don't think I've ever experienced such a straightforward alignment in my life. Both the UV and Green laser beams were able to be aligned on the optics table in really sensible ways. Chris started the software for alignment in the sky (to get the telescope and the laser beam to look in the same place for each other), and found that BOTH laser beams were within the field of view of the scope already. He didn't have to tweak the alignment much before starting the auto-align program. Even that procedure went well.

The only problem we had all day was one laser turning itself off because I left two cables plugged in that were not necessary (they're for when you only want to fire one shot at a time by pressing a button. I didn't know that the lasers don't like having them plugged in when they're not required), and the laser did not realize that when I put “P-zero-zero” in as a parameter, I really meant “P-zero-one”. It flashed once, and then stopped. Just like I told it to. I gave it some new instructions, and it did those, too. The right ones, this time.

In case you (especially Meike) are interested: I also spent time today staring down a tube at a smallish mirror under a dark inaccessible window at -50 C on a roof in order to watch said mirror rotate by one degree. Maybe less. Slowly. It was thrilling, let me tell you. [Yes, it was useful also. And didn't actually take that long. And I got to go outside during daylight hours.]

Smallish mirror down a dark tunnel. When it moves, it doesn't move much.

We came back to the station once both lasers were firing, and all detection channels were detecting. It's been on the go ever since! Calibrations on the depolarization channel start in earnest tomorrow with us drilling holes through boards.

The laser! What can I say? We tried it, and it worked!

Sham and I headed over to the 0PAL lab just after supper to get (re)acquainted with the lab, and to see whether we could get anything done in preparation for the next full day's work. This time, luckily, there was a) distilled water whose containers had not frozen themselves to the floor, b) a good sky for lidaring, c) no snow on our hatch (Thanks, Pierre and Mike!). The lab was in great shape, so after checking things out, we jumped right in.

We got the green laser firing out of the hatch, launched the data acquisition program, and (miracle of miracles) went to sleep while the lidar took care of running itself. We managed to get the emails sent by the lidar's alarm program (in case we need to shut down for snow or wind) to make audible alarms when they arrived in our inboxes. Sounds low-tech and like it should not be hard (especially if you're used to email on a phone... which I am not!), but is surprisingly hard to do on some Certain Brands of Laptop. Even when they have built-in features for the purpose. In any event, without the audible feature, the lidar operator has to wake up every so often and check on things. With the audio... well, it's easier. A Fancy Tablet worked great for me, and Sham's phone seems to be working for her.

In the morning, we woke up to a 9-hour data set in our visible channels.

This counts as a successful bonus lab day!

We made it to Eureka - and got a lot done

First things first: The lidar is measuring! Yay! We're doing the things we came here to do.

Four days after leaving home in London, we arrived in Eureka. With the delays in Yellowknife, I think most of us were actually more rested upon arrival than we would have been if we'd had two straight flying days in a row. 

We woke up at 5:30 am, breakfasted at the hotel at 6 am, and were at the Air Tindi terminal by 6:30 with all of our luggage. We flew in a Beech 1900D, and our pilots are familiar from past trips to Eureka. I don't know what kind of superpower turbo props they installed in that plane, because it's about the fastest three-legged trip to the lab that I've ever seen. We weren't on the ground long in Cambridge Bay before climbing back aboard en route to Resolute.

 This is Zahra. She's a PhD student at York University, and she was pretty excited about her first trip to Eureka (It's not her first trip to the Arctic; she studied in Sweden for 2 years). She's also my roomie this trip!

Resolute's weather behaved okay. The weather was fine all the way in, then we had some winds off the mountain which surprised us all a few hundred meters above the ground, and then Mitch set us down gently on the ground as though the turbulence had never happened. It went from “Hey, Resolute's got no wind, for once!” to “Ack! Bumpy! Don't like it!” to “Huh. Where'd the wind go?” and then we landed. No problem.

Aziz met our plane, we got fueled up, and were on our way again. Although we're early in the year, we had left early enough in the day to have daylight for most of the trip. In fact, we could see pretty well all the way in to Eureka. 

The Arctic just gets more and more beautiful as you travel North, and Ellesmere is the prettiest part! Lots of nice topography to keep things interesting, and with it all being various shades of snowy white, nothing is white at all. It's so pretty. The sun far to the south lights up the sky all sorts of colours, and the contrast of the sunlit peaks with the shadowed sides of the hills is just great. We were able to get good views of the PEARL lab and the road and the weather station on our final approach.

 We stayed up at the runway just long enough to say hello to some friends who were on their way back south, and then headed down for supper.

That would have made quite a nice end to the day, right? Except that with single-digit-numbers of days planned to be at the lab this trip, every one of them counts. A lot. Thus, it should come as no surprise that Sham and I were over at the lab at the first opportunity to see what we could sensibly get done.

Tuesday, February 25, 2014

Our little science group escaped from "hotel-arrest" today, after hearing in the afternoon that our plane would definitely not be leaving any time soon. We're aiming for tomorrow morning instead, pending weather.

We took advantage of the beautiful weather here to take another walk to some of the art galleries.

The Canada Goose jackets flying in a V. How appropriate!

We hit the usual Gallery of the Midnight Sun, and Northern Images, before heading for one that is new to us. This one had carvings done by the store owner and other local artists. These were done in alabaster, mammoth tusk, and the like.

Paul was our leader on the hunt for art.

Why not stop by the still-under-construction Snow King Castle while we're at it? The anonymous fellow in the wall shows just how thick the walls are. There's about 1 foot of snow, and then bricks of ice inside that. The workers are in the process of carving away the outer layer of snow to leave icy windows behind. The castle opens for visitors as of March 1st, so maybe we'll be able to stop in on our way back through YK.

Gravity waves, anyone?

Lovely view off the balcony this morning:

Prefer to read Sinhala?

See Sham's blog, too!

Check it out if you read any Sinhala/Sinhalese, and check it out just for the photos if you can't!

Sham climbed the hill to the Pilot's Monument yesterday, and got some different views of Yellowknife.

You'll notice that we are still in Yellowknife

Hi! We're still in Yellowknife, although we were ready to head to the airport for 6:30 this morning. We got the call while eating breakfast that our flight would be delayed. Why, you ask? Bad weather.

Weather in Yellowknife: Gorgeous. Just fine for flying. Beautiful.
Weather in Eureka: -50 C. Just fine for flying. Beautiful.

 (Yes, there's no weather forecast for the weather station. Go figure.)

The problem is with the airports on the way. We're taking a Beech 1900D this time, and have a lot of gear with us. We'll have to stop twice on the way, once in Cambridge Bay, and once in Resolute. This time, the delay is because of weather in Resolute Bay.

It's windy, with snow blowing. With no acceptable alternate runway nearby, our entire flight is on hold until the weather clears up.

Maybe by late tonight.
Maybe not.

I guess we'll wait and see!

Onward to Yellowknife

The flights to Yellowknife were not especially exciting, thank goodness. We met 7/8ths of the rest of the ACE team at our gate in Toronto, and traveled together. Paul met us in Yellowknife.

Dan with his new acquisition:

Dan and I are both learning how to use our new cameras.  We're anticipating many terrible shots as we learn all the non-optimal settings, and a few good ones here and there as we stumble upon something that works. We were practicing at the airport. 

It was chilly when we got to Yellowknife, but we decided to go for a walk anyways. Three of this year's team are on their first trip here, so we did the obligatory walk down to Old Town. It was really sunny, with clear blue skies.

I saw a couple of ravens (my favourite birds!) as soon as we got here, and Sham was interested to hear that they don't only caw like crows do, but they make other sounds as well. There might also have been some delight expressed about the funny sounds your boots make on the snow when the snow is really cold.

A little walk out onto Great Slave Lake brought us to the vicinity of the houseboats, the ice road, and the beginnings of the Snow King's castle.

Supper at the Black Knight, and then it was time for bed in preparation for our flight out the next morning, scheduled for 6:30 am. (Why so early, when we book a charter flight and can pick the time? It takes all day to get to Eureka, in 3 hops, and the more of that you can do in daylight, the better.)

Say “Hi!” to Sham!

Sham is a grad student in the same lab as me at Western. She's just starting to do Arctic research using the CRL, so we're both going on this trip. Her first experience with snow was this fall in London (she's from Sri Lanka), and she is wasting no time getting to even colder places. It will be nice to have some company at the lab, and this should give her an opportunity to get some experience with all the equipment and taking atmospheric measurements.
For those of you who recognize the concrete-laden shady location for the photo: For every time we make fun of people wearing Arctic-strength winter coats in Southern Ontario... Well, let's just say that Sham and I both broke out the parkas while waiting for a shuttle at Pearson Airport in Toronto. It was cold and windy, and we had to wait ages for the shuttle to show up after the first leg of our journey.

Sunday, February 23, 2014

What you missed while I was learning new facts about sheet polarizers last fall. Also: Hey, we're going back to Eureka!

It's that time of year again! The sun comes up on the Arctic, the polar stratospheric ozone does interesting things, and the ACE Validation Campaign Team treks back to Eureka to do an intensive measurement campaign. Thus, it's clearly time to write some blog posts!

If you only know me in blogspace (which is highly unlikely, but certainly possible), then you're one Eureka Trip behind the times at the moment. I was there in October/November for a couple of weeks doing some more calibrations. I learned a lot of things that I didn't know I'd ever wonder about.

I didn't THINK that I had blogged zero times on my fall trip to Eureka, but couldn't find any posts here today. Turns out that I was right... but that I had blogged somewhere else. Please consider the following transcription of the email I sent to my parents last fall as your Official Catch Up, and click on the link in it:

Hi Mum and Dad,
I wrote a blog post for our research group. It's here:
Critter count:
0 wolves
8 bunnies
2 muskoxen (one of which was running, so he gets bonus points)


That CREATE Arctic Science blog has things written by my fellow grad students, some of whom do research at Eureka. My post is just one contribution.  Check out in particular, if you want to see what's going on during the campaign in other ways.

If you're link-shy, here's a screenshot:

Part two of this post:

In case you are a scientist yourself, for school, or work, or because you like to tinker, here's a public service announcement of several facts:

1. Waxed paper CAN be a great depolarizing material. Not all of it is. Try various brands. Archival-Quality waxed paper ("Glassine") works better than any kitchen brand I've tried. You'll be familiar with this stuff if you are a museum archivist, but also if you've ever read one of those books that has a colour plate in it with that waxed-paper-like protective sheet over the picture. That waxed paper is the stuff I'm talking about. Buy a new pack from an art supply store, though. Don't hurt the books to get it!

2. Linear sheet polarizers. Three different brands threw us for a loop last November. Linear polarizers act like a fence, allowing through only light that oscillates in one plane, and blocking anything wiggling along a different plane. That's what I expected my sheet linear polarizers to do. They're way more affordable than crystalline polarizers (i.e. they do not cost 700$/one-inch-circle), and they're easy to transport because you can just roll them up. Turns out, (pun not quite intended, but I just noticed it :) that although these sheet polarizers allow only one plane of polarization to pass through (good!), sheet polarizers can ALSO send that light out the other side of the polarizer in not-the-same-plane-it-came-in-as (not so helpful!). If you have an application in which you put your detector directly behind the polarizer, you'll never know (or care) the difference. If you've got more polarizing optics downstream.... well, it makes a difference. Be warned. Not impossible to compensate for, but mighty confusing at 3am when you were not expecting your polarizer to do that.

More about our 2014 spring trip tomorrow as the team heads to Yellowknife!