Swedish fieldwork, part 2

Following on from the previous post on my Swedish fieldwork here is the belated second and final part.

Diary

I departed the UK early on Saturday 3rd March 2012 and returned the afternoon of Wednesday 21st March 2012. I spent:

  • Six productive field days
  • Five days in transit
  • Two office days – forced by bad weather
  • Two lost days due to equipment failure
  • Two days off
  • Two days carrying equipment to and from site.

Fieldwork

The field site was located just to the east of the Abisko National Park, and to the south of the research station. We had two options for site access, both of which were on foot. These were using snow shoes or cross country skis. Whilst show shoes are much better for steeper terrain or manoeuvring around trees, skis are a much faster way to travel over gentle rolling terrain with tracks! Because of this each day we skied up hill to the field site which took approx 1.25 hours, with an easy 0.75 hours downhill at the end of each day. Much harder in the dark though…

A portion of my time was spent helping Rob Holden with his fieldwork which involved taking repeat measurements along transects he surveys each year. Beyond this my time was spent taking hemi photos (figure 1) as part of the project described in my original post. The aim was to combine my fieldwork with that of Rob’s to maximise our sampling and so we worked together in a safe and efficient manner.

Figure 1: Hemi photo showing sky covered by trees.

Lessons learnt

With lots of time spent travelling to site you begin to appreciate not making mistakes, or having a backup plan, so here are a few lessons learnt over the course of the expedition:

  • Always have a backup fieldwork plan for each site day in case of an equipment fault or other issue with your original one
  • Travelling in a straight line on skis through a dense forest is hard, even sighting with a compass. If you want to take a transect enter it into a GPS in the warm back at base!
  • Skis are generally a much more energy and time efficient way to travel medium distances when compared to snow shoes, except when the terrain steepens
  • A snow scooter would have saved considerable time and effort when covering the long transects enabling a larger number of sites to be surveyed. There is obviously an increase in financial cost to consider when weighing up the benefits. Travelling through forest would be much harder on a snow scooter and there would be a temptation to travel on tree free areas and only move into the forest to survey, reducing the site distance to the edge of the forest.
  • The camera and tripod we used were very heavy (~5 kg), when not travelling by motorised transport this is immediately noticeable and severely affects the distance one is able to cover. The camera in particular is very expensive, which adds an unfair burden of responsibility to the user in a fieldwork setting
  • Radios do not work near a dGPS repeater or rover
  • Have an escalation procedure for if you don’t return from site one day…

Equipment

The equipment I used falls into three categories: data collection, clothing and transport. It’s probably important to note I haven’t received any sponsorship or endorsement from the companies detailed here.

To take the hemi photos I used a full frame Canon digital SLR fitted with a 190° fish eye lens. Whilst this is a good camera, combined with the tripod the weight was approximately 5 kg – which is a lot for fieldwork undertaken on foot! The GPSs we used were a mix of two Trimble dGPSs and a Garmin Etrex (the classic yellow one). The Trimble units are differential GPS units that use a base station connected via radio link to a rover allowing for a considerably more accurate measurement of location. The price for this increased accuracy is more gear to carry and a fair amount of effort ensuring the rover can connect to the base station. It’s no fun wading around in snow through dense forest with an aerial strapped to your back! Figure 2. The dGPS was used to locate previous transects required by Rob Holden, but was deemed not practical for the more remote hemi photo survey work. The Etrex unit provided a good compromise and Table 1 below shows a comparison made across 28 points between dGPS and the handheld Garmin unit.

Table 1: Comparison between GPS and dGPS, summary.

GPS-dGPS
Measure East (m) West (m) Elevation (m)
Minimum -3.96 -8.68 -10.81
Maximum 6.27 5.45 7.11
Mean 1.10 0.02 -1.37
Median 1.04 0.08 -1.11
Absolute mean 1.95 2.13 3.56
Absolute median 1.66 1.53 3.20
Standard deviation 2.18 2.92 4.36

Figure 2: Rob trying to manoeuvre with a dGPS. (copyright Michael Spencer)

Given the harsh conditions present in the Arctic during the late winter clothing plays a vital role in reducing the risk posed by the cold. The best bits of kit that did this were:

  • Montane Extreme smock: I can’t praise this jacket enough, the price is super low and the performance is exceptional. Worn next to the skin it dries out super fast and hence keeps you very comfortable. The jacket is a pile/pertex one with a high wicking inner overlain by a wind resistant outer. Compared to Rob, who used a traditional layered clothing system, I spent less time changing layers (only needing to adjust vent zips) and less time damp!
  • Montane North Star jacket: When we were stood around for long periods, the wind blew or it was very cold I’d pull this down jacket over the pile/pertex smock mentioned above. I’m a big fan of Montane kit for three reasons; I find the athletic fit works for me, the performance is very good, it’s well made
  • Buffalo mitts: Buffalo built the original pile/pertex clothing and still make top kit. Toasty warm wet or dry. The only downside with these mitts is that they’re not designed for holding, so do have the potential to wear out quickly if using ski poles a lot…
  • Muck-boots Tay Sport (Arctic in US, I think…): Very warm and unlike more traditional snow boots from Sorel are fully waterproof. Drawback is that your socks fall down if you walk around a lot!
  • Ron Hill Trail: Trusty pair of trousers. A fair bit thicker than the tracksters. Only downside is they don’t make them any more!

Transport was provided by backcountry skis purchased from Intersport in Kiruna. I got them on a deal with boots and to be honest I don’t know much more than that they’re metal edged, >2 m long and with some fish scales for forward propulsion! Being a skiing novice, in advance of the trip though I did take some lessons at the Midlothian Snowsports Centre. A fantastic facility if you ever have some spare time and are near the capital!

Results

After a busy summer I’m now beginning to work on the collected data with Tim Reid and Richard Essery. With a following wind we should have a paper out shortly!

In the mean time, here are some pictures from the trip:

Squeezy cheese, for champs (copyright Michael Spencer)

Skiing back to base as the sun sets (copyright Michael Spencer)

Towing the sled (copyright Michael Spencer)

Ice crystals on a frozen lake (copyright Michael Spencer)

Another late finish… (copyright Michael Spencer)

Clouds rolling (copyright Michael Spencer)

Hemi photos in action (copyright Michael Spencer)

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