Greenland Aquifer Expedition: Successful 2016 Field Season!

August 23rd, 2016 by Clément Miège
Nice cloud reflection on my last evening hike near the old harbor of Kulusuk.

Nice cloud reflection on my last evening hike near the old harbor of Kulusuk.

Hi there,

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.

Weather:

  • 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

Camping:

  • 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

Science:

  • 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,

Clém

Preparing our first sling load at the airport (left), ready to be picked up by the helicopter a few minutes later (right)

Preparing our first sling load at the airport (left), ready to be picked up by the helicopter a few minutes later (right)

 

Setup of our bear-proof camp. First, a trip wire which if tripped, triggers a loud alarm (sounds like a car alarm) and warn us about a possible encounter. The second layer of protection is a fence to shock the bear, and everyone had bear horns and bear spray. But we also carried a rifle in case the previous methods failed to scare the bear away.

Setup of our bear-proof camp. First, a trip wire which if tripped, triggers a loud alarm (sounds like a car alarm) and warn us about a possible encounter. The second layer of protection is a fence to shock the bear, and everyone had bear horns and bear spray. But we also carried a rifle in case the previous methods failed to scare the bear away.

 

Downloading data from both the Utrecht weather station (left) and our other station logging 50 temperatures in the firn and water-table level changes (right).

Downloading data from both the Utrecht weather station (left) and our other station logging 50 temperatures in the firn and water-table level changes (right).

 

Drilling (left) and processing the firn and ice cores (right).

Drilling (left) and processing the firn and ice cores (right).

 

Kip and Rick sampling water from the firn aquifer.

Kip and Rick sampling water from the firn aquifer.

 

Excavating ice columns and ice lenses after spraying neon-green dye at the surface to look at water infiltration processes.

Excavating ice columns and ice lenses after spraying neon-green dye at the surface to look at water infiltration processes.

 

Working after dinner on a small-scale seismic survey in nice the evening light.

Working after dinner on a small-scale seismic survey in nice the evening light.

 

Getting the MRS measurement started after setting up the 80 by 80 m loop. On the right, one of our logging station after one year of data collection, only the top of the mast (ARGOS antenna) is above the snow surface.

Getting the MRS measurement started after setting up the 80 by 80 m loop. On the right, one of our logging station after one year of data collection, only the top of the mast (ARGOS antenna) is above the snow surface.

 

Team photo on our last day with team members being hot in their ECW (extreme cold weather) gear! Actually, the tropical weather out there motivated us to pull out our leis too ;-)

Team photo on our last day with team members being hot in their ECW (extreme cold weather) gear! Actually, the tropical weather out there motivated us to pull out our leis too ;-)

 

Aloha! After 20 days of work, the helicopter is coming back to get us, we greet with Hawaiian style!

Aloha! After 20 days of work, the helicopter is coming back to get us, we greet with Hawaiian style!

 

Olivia hands our precious water samples to Johannes for loading them in the helicopter as our first priority.

Olivia hands our precious water samples to Johannes for loading them in the helicopter as our first priority.

 

Nick (orange helmet) has the last sling load ready to go and is getting prepared to hook it on to the cable attached to the helicopter.

Nick (orange helmet) has the last sling load ready to go and is getting prepared to hook it on to the cable attached to the helicopter.

 

Back in Kulusuk, we spent a few days packing up the equipment. On the last day a LC-130 came from Kangerlussuaq to pick up a few thousand pounds of equipment. You can barely see the small forklift from the airport moving the Air-Force pallet at the back of the plane.

Back in Kulusuk, we spent a few days packing up the equipment. On the last day a LC-130 came from Kangerlussuaq to pick up a few thousand pounds of equipment. You can barely see the small forklift from the airport moving the Air-Force pallet at the back of the plane.

 

Loading up the science equipment into the plane.

Loading up the science equipment into the plane.

 

Peaceful and sleepy husky puppies in the evening.

Peaceful and sleepy husky puppies in the evening.

 

View of the Kulusuk Island from the air. At the left you can see the airport runway and on the right, you might be able to spot the DYE-4 station.

View of the Kulusuk Island from the air. At the left you can see the airport runway and on the right, you might be able to spot the DYE-4 station.

Salinity Processes in the Upper Ocean Regional Study (SPURS): Meteorology for Oceanography

August 22nd, 2016 by Maria-Jose Viñas

By Eric Lindstrom

Launching a balloon from the R/V Revellle, for atmospheric sounding.

Launching a balloon from the R/V Revellle, for atmospheric sounding.

As I mentioned in a previous blog post, the R/V Revelle is bristling with meteorological sensors. Some are permanently installed aboard, some are just for SPURS-2, and some are on the moorings we will deploy. Raymond Graham, a graduate student at University of Connecticut, did a quick count of meteorological sensors and we were amazed to find out that on a ship of less than 300 feet we had deployed eight wind sensors, 16 air temperature probes, 15 humidity sensors, 15 rain gauges, 11 radiometers, and four barometric pressure sensors! The reason for the overkill is the critical nature of meteorology for our work and the difficulty of obtaining clean data from the ship. Wind and rain especially are notoriously difficult to sample because of flow distortions or shadowing around the ship. By deploying gear at a number of locations (bow, stern, bridge deck, etc.), we will more likely collect clean data no matter which direction the ship is headed relative to the wind. During analysis of the data, one ideal time series of ship data can be assembled from the numerous sensors based on ship heading and true wind direction.

Carol Anne Clayson at work on the bow mast.

Carol Anne Clayson at work on the bow mast.

For SPURS-2, a group from Woods Hole Oceanographic Institution led by Carol Anne Clayson and a group from University of Connecticut led by Jim Edson are gathering state-of-the-art measurements of key meteorological variables. They will estimate the transfers of heat, freshwater, and momentum between atmosphere and ocean. Today, for example, Jim Edson launched the first of their balloons for atmospheric sounding. The balloon carries a small expendable package that transmits temperature, humidity, and pressure data until the balloon pops in the upper atmosphere.

Elizabeth Thompson from the University of Washington's Applied Physics Lab.

Elizabeth Thompson from the University of Washington’s Applied Physics Lab.

Elizabeth Thompson from the University of Washington’s Applied Physics Laboratory is also working the meteorological angles for SPURS-2 by providing the daily meteorological briefings and analysis of radar data (to help us track rain events). She and Audrey Hasson are providing daily briefings at 4 pm to apprise us of the weather and oceanographic conditions to be encountered over the next day of operations. For the moment they are practicing and perfecting the best information and products to utilize and share. Prediction sure is an activity to sharpen a scientist’s skills!

Jim Edson from University of Connecticut  and Raymond Graham, a graduate student at U.Conn., looking over the first results from the balloon deployment.

Jim Edson from University of Connecticut and Raymond Graham, a graduate student at U.Conn., looking over the first results from the balloon deployment.

While much of the time aboard Revelle is focused on oceanographic measurements, the meteorology is key to synthesis of the overall story of SPURS. In the end we will want to assess the ocean response to forcing – whether in the form of rain, wind, or sun’s radiation. It is quite difficult to tell the story of the near surface ocean without understanding how it is interacting with the atmosphere. Likewise, it is quite difficult to tell the story of the evolving atmosphere without understanding how it interacts with the ocean. This coupled system is an especially powerful engine for Earth’s climate here in the tropics. The warmer the ocean and atmosphere, the more energy in the form of water vapor is exchanged. Hurricanes are a good example of this interaction and exchange – and a reason to worry about stronger or more frequent hurricanes in a warmer world. Air sea exchange is very sensitive and very powerful when ocean waters are greater than about 83 degrees Fahrenheit (28.5 degrees Celsius) as is found in the deep tropics and here in the Intertropical Convergence Zone.

ATom 2016: World Survey of the Atmosphere: Going Back in Time

August 19th, 2016 by Roísín Commane

As the DC-8 flies around the world for the ATom project, we are crossing many time zones and occasionally loosing and gaining days! For most of the first half of the project, I didn’t really notice these time changes. I gained the most time leaving Boston for California and had one to two hourly stretches in the evening after that. This has meant that getting up for 4 a.m. pre-flights has actually been do-able! I thought I was doing great — for a night owl. We lost time last week when flying from American Samoa on Monday morning and arriving into New Zealand on Tuesday afternoon. But I had already lost track of the day of the week so that didn’t really have any impact on my routine. In New Zealand, I finally had the time to take a whole day off (for the first time in over 2 weeks!) so we explored Aoraki/Mt. Cook National Park for a few hours.

Snow blowing from the mountains onto the glacier in Aoraki/Mount Cook National Park, New Zealand. Credit: Róisín Commane

Snow blowing from the mountains onto the glacier in Aoraki/Mount Cook National Park, New Zealand. Credit: Róisín Commane

And then there was the flight from Christchurch, New Zealand to Punta Arenas, Chile.

We gained back the lost day and more as we flew 10 hours from Christchurch on Saturday morning to arrive in Chile at 4 a.m. on Saturday morning. My poor body clock has no idea which way is up! On the plus side, maybe this body clock mayhem will make the 3:30 a.m. wake up call for our pre-flight tomorrow slightly less ruthless? Wishful thinking perhaps.

But at least the flight from New Zealand was worth all the effort! We flew south from New Zealand to 65 degrees S, profiling from the top to the bottom of the atmosphere as much as we could. We saw Antarctic sea ice, lots of sea salt particles and not at lot of CO at the low altitudes, while at the highest altitudes we saw the Polar vortex and its -70 degrees C temperatures. We also saw CO2 over 401 parts per million (ppm) for most of the flight.

Watching the sun set mid-way through our flight from New Zealand to Punta Arenas, Chile. Credit: Róisín Commane

Watching the sun set mid-way through our flight from New Zealand to Punta Arenas, Chile. Credit: Róisín Commane

There is a wonderful exhibit in our hotel here in Punta Arenas about Shackleton’s Trans-Antarctic Expedition (1914-1917) from Chile to Antarctica, which included the great Irish-man Tom Crean. Disaster befell the expedition in Antarctic waters and resulted in five men (including Crean and Shackleton) sailing a 20-foot boat across 700 plus miles of Southern ocean to get help. After seeing the choppy seas of the Southern Ocean on our last flight, I have no idea how they found the island of South Georgia. But hopefully we will have just as good luck as they did when we venture east again to find Ascension Island in the middle of the South Atlantic tomorrow.

Our first sunset in Punta Arenas, Chile. Credit: Róisín Commane

Our first sunset in Punta Arenas, Chile. Credit: Róisín Commane

Salinity Processes in the Upper Ocean Regional Study (SPURS): Satellites and Salinity

August 19th, 2016 by Maria-Jose Viñas

By Eric Lindstrom

A representation of the SAC-D spacecraft, which carried the Aquarius instrument.

A representation of the SAC-D spacecraft, which carried the Aquarius instrument.

One of the most common questions I get (and the first comment to this blog) is “How do you measure ocean salinity from space?” During the SPURS-1 campaign in 2012 I wrote a blog post on this topic. Basically the story is one of building a very sensitive instrument (a radiometer) to detect subtle variations of L-band microwave emissions from the ocean. Aquarius, launched in June 2011 was designed specifically for that purpose. Unfortunately, the spacecraft on which the Aquarius instrument flew suffered an unrecoverable failure in spring of 2015. Fortunately for oceanography, NASA launched Soil Moisture Active-Passive mission (SMAP) in January 2015. SMAP uses similar technology (an L-band radiometer) to measure soil moisture. While SMAP is not as sensitive as Aquarius, NASA is successfully producing a salinity product from this mission’s data.

The satellite missions detect only the salinity at the surface of the ocean. This tells us much about the exchanges of water with the atmosphere once we learn how to interpret the signals. The SPURS expeditions are all about learning how the surface salinity of the ocean changes so we can use the global surface salinity maps from space to diagnose matters of the water cycle over the ocean.

The European Space Agency also launched the Soil Moisture and Ocean Salinity mission (SMOS). It uses a different technology (a synthetic aperture antenna array) to make the measurements, but also provides a salinity product we use daily. Audrey Hasson from the French space agency is aboard R/V Revelle and helping us bring all the space data (salinity, temperature, winds, sea height, waves) to the ship to guide our daily operations.

Audrey Sasson, from the French space agency, aboard the R/V Revelle.

Audrey Hasson, from the French space agency, aboard the R/V Revelle.

Most of the oceanographic work on this voyage is focused on measuring and understanding the variations of salinity in the top 10 meters (~30 feet) of the ocean. Here, in one of the rainier spots on the planet, rainwater freshens the surface ocean. The degree of freshening was not really appreciated until we saw the surface salinity from space. Measurements from ships and buoys usually miss sampling the upper few meters of the ocean because it is technically difficult to make those measurements. Taking full advantage of Aquarius and SMOS surface salinity observations has required a scientific revolution in measurement of salinity in the top 10 meters of the ocean.

Getting back to shipboard life, I am happy to report that all the minor cases of seasickness are abating. Those that suffered from it are now smiling and eating. No serious cases of seasickness occurred at all, so my guess is that all the first-timers will return to sea in future!

Deploying the Surface Salinity Profiler.

Deploying the Surface Salinity Profiler.

Also, today was the first trial deployment of one of our key instruments, the Surface Salinity Profiler (SSP), from University of Washington Applied Physics Lab. It’s a salinity measurement “laboratory on a sailboard” that can be towed at outboard of the ship. The instrument can measure salinity simultaneously and continuously at several shallow depths away from the ship’s influence and wake. The trial was devoted to the mechanics of deployment and recovery and the dynamics of towing the system. You will hear much more about SSP as the voyage progresses.

Recovering the Surface Salinity Profiler.

Recovering the Surface Salinity Profiler.

Winds dropped over night and whitecaps have largely disappeared. The sky is broken clouds with an occasional very light rain shower. Air temperature is 80°F. So overall, the weather conditions for test deployments off the ship are much better today!

Salinity Processes in the Upper Ocean Regional Study (SPURS): Preparing for Action

August 17th, 2016 by Maria-Jose Viñas

By Eric Lindstrom

Our wave gliders, ready for action.

Our wave gliders, ready for action.

Fieldwork in physical oceanography, like many sciences, requires enormous preparation followed by a shorter very intensive period of action. SPURS-2 is no exception. The work over the next six weeks has been in the planning and staging for several years. Now, all the gear and scientists have reached the ship and we are on our way to completing all of our the carefully laid plans.

It is tempting to express the mood aboard the R/V Revelle as a great sense of anticipation. From discussion around the ship, it seems like no one has seen a voyage with these many sensors and equipment installed aboard this ship. There seem to be instruments mounted everywhere from bow to stern! And, of course, the scientists and technicians are deeply interested in what each sensor will tell them and what kind of scientific discoveries will emerge. These instruments are designed to see the delicate slow dance between the ocean and atmosphere around the ship over the coming weeks. Other gear will be deployed to continue the careful watch on ocean and atmosphere for the next year. All our time and investment is focused on understanding the aspects of this “slow dance” that involve water exchanges between ocean and atmosphere. In the atmosphere we will be looking at the characteristics of rainfall and evaporation at the sea surface. In the ocean we will be study the characteristics of the temperature and salinity patterns induced by the rain. These interactions are a newly accessible field of study resulting from the advent of satellite rainfall and salinity measurements and new shipboard tools for studying the upper few meters of the ocean.

One of the numerous meteorological masts installed on the R/V Revelle for SPURS-2.

One of the numerous meteorological masts installed on the R/V Revelle for SPURS-2.

All the scientific party on R/V Revelle likely feel some sense of adventure, since the precise nature of what we will see and discover is a matter of conjecture. We do know from the Aquarius satellite data that there is a large pool of relatively fresh water built up seasonally at the surface of the eastern tropical Pacific north of the equator. Oceanographers are curious as to how this pool is trapped in the region for part of the year and how it is seasonally released to the west. As physicists, we are tackling the problem by careful examination of the individual processes that bring the water into the ocean (rain), maintain the fresh pool in the ocean (dynamics), and subsequently release the water to the west or to the deep (dynamics and mixing). If we knew the answers, it wouldn’t be research. The unknown beckons! The combined feelings of curiosity and anticipation –and that our work may result in deeper understanding of nature–, just seem to make this feel like an adventure!

The chief scientist of SPURS-2, Andy Jessup, is ready for action too.

The chief scientist of SPURS-2, Andy Jessup, is ready for action too.

So here we are, all primed for discovery but with five days more to go before being where we really want to work. We are like kids in the back seat of the car asking “are we there yet?” Every piece of gear is at the ready and the teams are completing their training. We are doing dry runs to iron out the deployments of new devices that just have not seen that much action. In later entries, I’ll introduce you to the Sea Snake and the Surface Salinity Profiler and the Lighter-than-Air InfraRed System (LTAIRS), a balloon. These are very new ways of examining the air-sea interaction near the ship. They will be used in conjunction with many of our standard tools – drifters, wavegliders, and moorings, for example. We hope they will lead us to deeper insights about the water cycle at the ocean surface. I will give you a preliminary view of what is discovered during the week-long return voyage to Honolulu at the end of September. For now, we simply prepare for action!

Notes from the Field