Laser Broke So I Went on a Trip

During the Winter it is one of my obligations to run the lidar for a few sessions that comprise more than two full days of consecutive observing each. Adam, electronics engineer that I mentioned in the last post, and I decided to get an early start last week when the forecasting models predicted a 3-day break in the clouds. May at Davis Station has been marred with constant cloud so this seemed like a perfect opportunity.

The lidar is capable of recording data that will give temperatures up to about 80km, though the higher you look, the more sensitive-a-detector you must use, and so are more likely to damage the detector with strong backscatter from low-altitude signals. We're still interested in the whole atmosphere; from tropo-, through strato-, into a big chuck of the meso-sphere, so we run a 'combined schedule' that spends about 48 minutes gathering data at altitudes at 20km-80km then quickly switches to gathering data from about 5km-40km for 8 minutes, just to make sure there aren't any sneaky clouds hovering around 20km. You see, in the next few weeks, we expect to see increasing detections of Polar Stratospheric Clouds (or PSC's) at this altitude. These clouds are interesting because they act as a catalyst for the breakdown of ozone. The small particles in the clouds provide surface area for chemical reactions to take place that allow the chlorine free-radicals from CFC's to snatch one of the oxygen atoms from the O3. I think I mentioned something about this in my last post. The more clouds we see, the bigger we should expect the ozone hole to be. By comparing our detection of PSC's with the ozone-concentration data gathered from the big ozonesonde weather-balloons that the slackers from Met let off once a week, we get more data about the relationship between the two.

So we ran the lidar doing some haphazard kinds-of shifts that somehow had me working till 6am the first morning, and then switching so as to be up at 7am the following morning for slushy, aka. kitchen duty that each station member does every 25 days. It didn't help that upon finishing up at 2am the night before I decided to join Chris the Dieso in getting pissed for his birthday and retiring 2hrs30mins before I was required to start said duties. Well, I was only 40 minutes late! Thanks Adam for backing me up on this too.

During the guts of the Thursday (we ran lidar from 5pm Wed to 6pm Fri) I went out and performed my weekly duty of ice-drilling at 7 sites out the front of station with Nick "the Rodent" Roden, a met observer and amateur film-maker that keeps putting cameras in our faces. Bother us now it may, but I reckon we'll be pretty stoked to have his footage when we get back home. Anyway, wrt to the sea-ice drilling, I'll put up a map of the location of the sites where we drill because it'll make it seem real to you. I really enjoy doing this because it's a weekly reason to get out on the quad bikes for some fresh air. Our measurements show that the ice has been growing consistently and is now about 85cm thick in places. This is more than enough to support heavy machinery, let alone people, quad bikes, and hagglunds.

So anyway not long after I got back from the ice-drilling and got some more sleep and then took over from Adam (to begin the evening with the finishing at 2 and the drinking and the like), the laser power started reading 13W, as opposed to its usual 25W that I'm so comfortable and familiar with. Shit. I shut down the laser and blasted all the optics with high-pressure air so as to remove any bits of dust etc that may be diverting some of the laser power from its path up the chimney and into the sky. This didn't seem to have any effect. I checked that the laser power meter was not playing up by substituting the spare detector-head and this didn't do anything either. Bugger. This isn't something that you want to deal with; there were a range of possible problems that may be causing this and many of the solutions involve painstaking hours twiddling mirrors with an ever-present feeling of futility looming overhead. Adam and I decided that the twiddling and the futility could wait, and that we would take advantage of the rare clear skies and finish our marathon observation, worrying about the tiny problem of the laser being half-broken at some other time.

So we finished our observation, limping along at 13W. I packed things up, sent off the data, and went down for some dinner and sleep. The next day I would be going out on a jolly, or field-trip, to Platcha Hut and I made sure I got a lot of rest. See, you can see my name on the whiteboard to the left. The ailing laser was in the back of my mind and I felt a slight but easily-suppressed twinge of guilt the next day as we rode out over the sea-ice away from the colourful buildings of the station. The sun was rising/setting the whole time we were riding, providing some amazing fiery reds and oranges that complement the blues and whites of the icebergs and sea-ice. The air was nice and still, and I think it was about -15 that day, which isn't so cold when you've got the right gear on and the electronic hand-warmers on the quad hand-grips are firing away. We drove north up the coast and then diverted into Long Fjord, which is just as thick as the frozen sea-ice, all the way east towards Platcha Hut. The ride went smoothly for the most. Exception: at one point, while pushing through a geographical bottleneck so determinedly, with visors down and heads to the howling wind, the two of us at the front had forgotten to turn around and perform our regular check to see how our companions were travelling. By the time Ali and I looked back we could barely see Kim and Spaggers, far behind us in the narrowest part of the wind funnel. Turning, back we returned to this now inexplicably calm section of ice running between two hills to see that the two stragglers were utterly bogged; snow up to their footpegs. It took the muscle of 4 people and a barely-gripping quad to reverse the thing out of the slush, but we did it. The most concerning thing about this was that under the snow the wheels of the quads were splashing up water, which implies a breach in the ice underneath at some point. Nobody fell through, but we have noted that it would be better for other travellers to take a mapped-detour to the right next time. We just don't know where that water came from.

So we got to the hut and spent two nights there. We were all treated with wonderful food from our excellent chef Kim and with good conversation from each other. Good weather wasn't so forthcoming so we spent the whole weekend holed-up in the tiny cabin reading, doing puzzles, chatting and sharing meals and drinks. It was a wonderful and relaxing time, and I was sorry when it came to an end. We headed back to station yesterday and arrived back at 2pm. I did nothing for the rest of the day and found it pretty hard to do anything today as well. Going out the hut had put me down a gear and I was still trying to spin-up until about 3pm today. Here I've added a picture of Kim, Ali, and Spaggers enjoying some warm chocolate custard for dessert. You can see me bowl behind Ali's, waiting to be set upon by me right after I put down the camera.

Now here I am and I've gone and written all this which has caused me to become alert and enthusiastic at 11:30pm. Ah doesn't matter. If there's something I hardly ever have trouble doing, it's sleeping, which I'll go and do now.

See ya later. I'll put some photos up later on. I didn't take too many though. It takes you outta the moment too much and I don't like it.

Also, at noon today I discovered that the laser is fine, and that the problem was some sort of glitch with the power meter. Crisis averted.

Goodbye. May delicious chocolate custard warm your bellies this Winter.

Really, Really, Really tasty