Last blog post of for this field season, as Olivia mentioned in her science post, we were able to collect an important amount of high-quality data to further our knowledge of firn aquifers and try to answer the following research questions:
- How fast is the water flowing in the firn aquifers? How permeable is the aquifer?
- How old is the aquifer? Is it growing inland from year to year?
- How much water is contained in it?
- How fast the meltwater infiltrates from the surface to replenish the aquifer?
- What is the depth to the water table and how thick is the aquifer?
To learn more on how we try to answer these questions, I invite you to read Olivia’s post where each method is described in more details.
To wrap up, I am using bullet points and I am dividing them into themes: weather, camping, and science.
- 20 days spent on the ice (2 more than last year!): 18 sunny days and 2 overcast days
- Less than 5 knots wind on average. Windiest morning being the day when we moved our camp downstream to add a bit of challenge to set up tents.
- No significant snowfalls this year – only a few snow flakes!
- Daily air temperature around 0°C in average with our coldest nights at -7°C (in our last days) -> warmer on average compared to last summer therefore a bit slushier
- No polar bear encounter!
- 2 bear-trip-wire false alarms at night, which scared us but only for a few seconds!
- 60 Gallons of fuel consumed between our snowmobile and our generators
- 200-km added on the snowmobile odometer
- About 90 dehydrated meals eaten with best pick for this year being “Beef Stew” and “Lasagna with meat sauce”. The least favorite was, surprisingly, “Biscuits and gravy”
- Hundreds of instant coffee, hot chocolates, ciders…consumed
- Few dozen of hot water bottles being brought to our sleeping bag to keep us warm during the 20 nights camping.
- Bunch of hand warmers being used for hand and toes or to keep instruments and laptops warm
- Long days typically 9 am to 7-8 pm.
- 12 seismic lines (forward and reverse lines) done with about 4000 hammer swings including 48 30-stack shots to get ourselves fit!
- 12 MRS sites visited with a mixed of revisit from 2015 and new sites
- About 120 m of ice cores analyzed (at 3 different locations)
- A few hundreds of water and ice samples obtained to be analyze their chemistry back at the lab (~ 80 L of water)
- 150 km of ground-penetrating radar data collected with a depth to the water table oscillating between 25 feet and 90 feet spatially.
- 1 year of weather station data collected including air temperature, pressure, long and short wave radiations, surface changes…
- 1 year of water-level and firn temperatures recorded in conjunction to the weather data
- 5 GPS base stations to measure surface velocities
- Two logging stations and one weather station dug out and raised up at the surface.
- One new logging station installed to measure water-table level changes, compaction rate and air temperature.
- 6 batteries recharged for powering our logging stations between Aug 2016 and Aug 2017 –- knock on wood!
- 18,000 liters (~280 showers) of water pumped out the aquifer during a 5-h pump test. At a rate of 1 liter per second! We did several pumping tests for a total of 90,000 liters.
- A total of ~ 100 GB of data collected (all methods combined)
That is about it for our fieldwork summary, below, I have tried to summarize our work with photos in a chronological order. I hope you enjoyed reading the different blog posts and on the behalf of our team, I would like to thank you very much for following our journey in Southeast Greenland.
All the best and see you next time,