WISSARD Fast Facts
Excitement draws near as we are attempting to make Antarctic scientific history by drilling into a subglacial lake using clean access drilling and then using special instruments for sampling procedures. Drilling is going well and the WISSARD team is working hard at the Subglacial Lake Whillans (SLW) field camp/drill site. If everything stays on track, they expect to reach Lake Whillans in the next two days. As we all know, anything can happen here in Antarctica. As one friend reminded me: “nothing is for sure unless it’s already happened.” We all need to be patient and hopefully we’ll have big news soon!
Meanwhile, I want to review (and for those of you who might be new to the blog this is a great introduction) a few of the most important “fast facts” about the WISSARD Project. Before I start, here are two aerial photographs taken by Lead Scientist John Priscu as they approached the field camp on the flight out a few days ago. Notice how tiny the camp looks from a distance.
Now things are coming into focus a bit more and you can make out some of the containers that serve as mobile laboratories and places to house drilling equipment and tools. It looks small, but if you’ve been reading my blogs you know that it took 13 tractors two weeks to tow all of those containers and the equipment out over 600 miles on the Ross Ice Shelf to reach the area above subglacial Lake Whillans.
A Basler dropped off some of the WISSARD’s a few days ago. The pilots land the Basler and Twin Otters (the smaller planes) close to the SLW site. The Hercules aircraft land about six miles away from camp and people are transported to the site by snowmobile or Pisten Bully.
Here are some “fast facts” about the WISSARD Project.
- A subglacial lake is a body of liquid water located in between an ice sheet and the continental land mass. The water remains liquid because the ice sheet above the water acts as an insulator and traps geothermal heat from the Earth’s crust.
- There are over 300 lakes thought to exist beneath the Antarctic ice sheet.
- Many of the lakes are interconnected with water flowing from one lake to another other via streams and wetlands
- Some lakes like Lake Vostok under the East Antarctic Ice Sheet retain water on the order of the 10,000 years, while others like Lake Whillans only retain water on a decadal scale
- The presence of liquid water beneath the ice sheet can affect its movement, therefore understanding a subglacial waterway is crucial to understanding ice sheet stability.
- Subglacial lakes are pertinently cold and dark environments that could add to our understanding of the evolution of life in these extreme environments on earth and other celestial bodies.
Subglacial Lake Whillans
- Lake Whillans, formally known as Ice Stream B, was named for Dr. Ian Whillans, an Ohio State University glaciologist who was central in understanding the crucial role that ice streams have on overall ice sheet stability.
- Lake Whillans is located 0.5 mile (800m) underneath the surface (this distance is the equivalent of you running around an outdoor running track twice).
- The lake is approximately 30 feet (10 meters) deep and 23 miles2 (59 km2).
- Lake Whillans is considered to be an active lake that goes through periodic filling and draining cycles, retaining its water on a scale of decades
- The water present in Lake Whillans is thought to flow directly to the Ross Sea, making the lake a direct link between the unexplored subglacial environments of Antarctica and the global oceans.
The Science of WISSARD
- WISSARD has 14 Principal Investigators from 9 different institutions across the nation
- During the Antarctic summer of 2012-2013, the WISSARD camp will be home to ~40 scientists, drillers, and support staff. They will sleep, eat, and work on the ice cover above Subglacial Lake Whillans for about one-two weeks.
- A hot water drill will melt through the ice to the Subglacial Lake Whillans half-a-mile below the surface.
- This is the first opportunity scientists have had to directly study what is one of the planet’s last frontiers.
- After 2 days of drilling, the science team will have about 5 days to collect water and sediment samples and conduct experiments in the WISSARD field labs.
- Water and sediment samples will be retrieved from the lake by lowering sampling devices attached to a winch carefully through the hole in the ice into the approximately 30 foot deep water column.
- Robotic tools will explore the physical characteristics of the lake cavity, while other instruments will collect physical and chemical measurements directly in the water column
- The project is likely to discover new types of microbial life in the lake water and sediments and will provide information on the importance of the flow of subglacial water under the surface of Antarctica.
The pictures above depicts the types of tools and instruments WISSARD scientists will be using to gather information about water and sediments in Lake Whillans. Some instruments are quite large/long, while others are much smaller.
The photo below demonstrates how special precautions are taken to provide clean access. Clean suits and gloves are worn, instruments are cleaned and packaged in plastic until deployed, to keep them from contamination.
Hot Water Drilling and Clean Access
- Drill Components
- Drilling operations are conducted and monitored from a command and control module.
- Water is supplied by melting snow in a melt tank. From there it is stored in a 4500 gallon holding tank.
- 225 kilowatt generators supply power for drilling, camp, and science operations (they generate enough energy to power Scott Base, the New Zealand research station)
- The water used for drilling is heated by 6 Alkota power units (984 kilowatts of thermal energy), all housed in two 40-foot shipping containers.
- A third shipping container holds the main hose reel, return water system, instrumentation manifold and hose washing system.
- A fourth container houses the clean access filtration unit than uses UV radiation and filtration to kill and remove micro and sub-micron particles (biotic and abiotic).
- As part of clean access, all instruments and cables are washed with 3% hydrogen peroxide
- The top of the borehole is protected by a UV radiation collar, through which all instruments and cable travel.
Drillers are busy melting water for the hot water drilling system.
Here is an example of one of the WISSARD instruments being carefully lowered into the test borehole back in December.
- 13 Challenger and Case-IH tractors, each capable of pulling 100,000 pounds, have driven over 600 miles from McMurdo to Lake Whillans.
- The tractors drive at an average speed of 7 mph and carry 36,000 gallons of fuel.
- The traverse is moving all drilling equipment, science labs, and several camp structures.