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Thursday, March 5, 2015

One week to go

The intrepid ICE-MITT team
Wow.  Where does the time go?  Ellyn and I did a radio show Tuesday night (you can listen to the podcast here: http://photographybydennisprice.weebly.com/radio-hotline.html) and it suddenly struck me how quickly the time has gone.  When doing work in the poles, it is well known that the best laid plans are really only suggestions/guidelines at best.  However, during the planning stages of this project, I truthfully thought that the field portion here in Barrow was going to be very relaxing and restful (at least in comparison to the crunch I had been in all fall trying to build the ICE-MITTs).  We only had 10 ICE-MITTs and wanted both spatial and temporal variability in our core collection over the 6 weeks we would be here.  We had briefly discussed collecting a few cores immediately from several different locations, perhaps a couple of cores in the middle, and then the final cores during our last few days.  If all goes smoothly (ha!), it really didn't sound like a ton of work.  I even started thinking that I could catch up on writing papers from past projects during all of the "free" time that I would have.  Well, for those of you who have closely followed all of our adventures or have spent any time in the Arctic/Antarctic yourself, no explanation is necessary to find where 5 weeks went (thin ice, misbehaving ICE-MITTs, broken ice cores, an electronics graveyards, weather, polar bear encounters, etc.). 

Installing the wire harp
Well, for those keeping score at home, we currently have 7 ICE-MITTs running and 3 ICE-MITTs empty and awaiting cores from the final week.  We have found several good coring locations for spatial variability, have kept a steady schedule for temporal variability, and without a doubt have had quite a bit of weather variability.  We have also twice cut out a 3 ft by 3 ft hole in the ice and installed a "wire harp."  We are using this to measure electrical impedance and temperature of the ice as it grows.  Yesterday, we realized for the first time that we were both ahead of schedule scientifically and had beautiful weather.  Thus, we took the opportunity to collect some "free" extra data points for our last project.  If you recall, this project involved erecting a blowing-snow catching tower.  We then analyzed the chemistry of the blowing snow to determine at what point salts such as bromide are converted into reactive gases (e.g. bromine) and participate in ozone depletion events.  When your research requires expensive field campaigns, you do not let a day (especially a beautiful -15 ºF and only 10 mph winds day) go to waste.

The snow catcher back in action
So what's next?  Immediately in our future is 1 final week of collecting 3 ice cores, packing everything up, chartering a plane to Fairbanks, and starting the epic ICE-MITT: The Tour road-trip home.  However, once we get back to Dartmouth and relax for perhaps 85 seconds, we get started on analysis before the ICE-MITTs decide they are tired and want to quit.  This involves cutting up the ice core and taking small 1" cubic samples to analyze with a micro-CT (think Cat-Scan at the hospital, except smaller and inside a cold room).  This allows us to create a virtual 3-D reconstruction of the sample showing the ice, air pockets, and brine channels.  At this point, we get to invoke all of the fun mathematics of topology to describe the network of brine channels, and analyze how transport processes are controlled by the microstructure.  If this sounds interesting to you, please let me know as we have endless hours of samples to run on the micro-CT and haven't you always wanted to put chunks of ice into a CT machine?

Micro-CT image showing brine channels of different sizes in different colors

2 comments:

  1. Now I finally understand what you are doing with the ice cores. In the words of Colonel Clink (from an old TV show Hogan's Heroes), "Verrrrrrrrrrrrrrrrrrrrrrrry interesting . . . but not funny!"

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  2. Ross, are you sure you won't want to relax for 86 seconds like I would do?? lol, there goes that 85 number again!

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