British team set to access and sample one of the last unexplored environments on Earth
Press release issued: 12 December 2012
This week, a British team of scientists and engineers, led by Professor Martin Siegert of the University of Bristol, realise a 16 year ambition to drill down through over 3 km of Antarctic ice into an ancient buried lake. The team hopes to find signs of life in the water and clues to the Earth’s past climate in the mud at the lake floor.
Using a high-pressure hot-water drill specially designed for the mission the 12-man team will begin boring a hole through solid ice into Lake Ellsworth on the West Antarctic Ice Sheet today [Wednesday 12 December]. It will be a race against time to keep the access borehole open long enough to lower and raise two state-of-the-art instruments that will collect water samples from the lake surface to the lake bed, and a core of mud from the lake floor. The team can only keep the borehole open for 24 hours before it refreezes to an unusable size, ultimately sealing the lake off again.
More videos on Lake Ellsworth's YouTube channel.
Precision engineering and technology are at the heart of this scientific experiment. The hot-water drill, designed by British Antarctic Survey (BAS) engineers will take around five days of continuous drilling through the ice to reach the lake. A titanium probe, designed by a team at the National Oceanography Centre (NOC) will collect water samples and data. A sediment corer developed by BAS with Austrian partners will capture lake-bed mud samples.
The science team thinks that unique forms of microbial life could have evolved in Lake Ellsworth’s extremely cold, pitch black and pristine environment and these may have been isolated for up to a million years. If so the lake will provide clues about the potential origin of and constraints for life on Earth, and shape scientific thinking about the evolution of life on other planets. If no life is found this would be an equally valuable result that indicates the limits of life on Earth. Sediment samples (mud) from the lake are expected to yield important insight in to the ancient history of the West Antarctic Ice Sheet and reveal vital secrets about the Earth’s past climate. This will have implications also for our understanding of future sea level rise.
It has taken the ‘Deep Field Team’ four weeks to set up living and working facilities at the camp; to prepare and test the drill rig; and ensure final sterility measures are in place before drilling commences.
The drilling mission is made up of four-stages:
1. Pump a high pressure jet of hot water slowly into the ice to create a borehole that is around 40cm wide
2. Create a chamber in the ice (the size of a caravan) 300 metres below the surface, fill with hot water, place a water pump inside to balance the pressure and prevent lake water rushing back up the borehole when the lake is penetrated. This should take around two days of constant drilling
3. Continue to drill the borehole for approximately three days more, going deep through the ice and into the lake
4. Lower and raise the instruments to retrieve water and sediments samples for analysis in UK laboratories – the team has just 24 hours to complete this stage before the hole re-freezes to an unusable size.
To protect Lake Ellsworth’s pristine environment and to ensure that uncontaminated samples are brought back to the UK for analysis, space-industry-standard clean technology has been used to sterilise every piece of equipment. This included a four-stage chemical wash followed by full exposure to hydrogen peroxide vapour (HPV) during the final assembly process. All equipment was transported from the UK in sterile packaging and will be treated with HPV again on site. The water used for drilling will undergo a four-stage filtration process, down to 0.1 microns, before being passed under UV light and heated to 90 degrees C.
Lake Ellsworth Principal Investigator Professor Martin Siegert from the University of Bristol said, “This British mission is part of an international effort to discover and explore subglacial lake environments. We are about to explore the unknown and I am very excited that our mission will advance our scientific understanding of Antarctica’s hidden world. Right now we are working round the clock in a cold, demanding and extreme location – it’s testing our own personal endurance, but it is entirely worth it.”
Lake Ellsworth Programme Manager and Expedition Leader Chris Hill from British Antarctic Survey said, “A major milestone last year was getting the bulk of the equipment and supplies to the site - the logistical effort alone to get 100 tonnes of equipment to Lake Ellsworth has been phenomenal. Now everything we’ve planned and prepared for is about to happen and it’s tremendously exciting – if not a little nerve-racking!”
Lead Hot-Water Drilling Engineer Andy Tait from British Antarctic Survey said, “This is a huge, but delicate operation. Although hot-water drilling technology has been used extensively by scientists in the past, this is the first time we’ve ever attempted to go through 3km of solid ice - this will be the deepest borehole ever made this way. We’ve fired up the boilers to heat the water to 90°C. The water pressure coming out of the hose will be around 2,000 PSI – 15 to 20 times more powerful than the kind you wash your car with. It is the most effective way to obtain rapid, clean access to Lake Ellsworth.”
The Lake Ellsworth Consortium is funded by the Natural Environment Research Council. It features two of NERC’s Centres of Excellence – British Antarctic Survey and the National Oceanography Centre – and nine UK universities.
For regular updates on the team's progress, visit the Lake Ellsworth blog.
Three academics from the University of Bristol's School of Geographical Sciences are part of the Lake Ellsworth project. Principal Investigator, Professor Martin Siegert and aquatic biogeochemist Professor Martyn Tranter arrived at the drill site in Antarctica on 4 December. Some of the water samples retrieved will be analysed back in Bristol next year by biogeochemist Professor Jemma Wadham.
Professor Martin Siegert
Martin Siegert is Professor of Geosciences in the University of Bristol's School of Geographical Sciences. He is the Principal Investigator on the NERC Consortium Grant award and Chair of the subglacial Lake Ellsworth Steering Committee and Programme Board.
He initiated the subglacial Lake Ellsworth programme, gathered the consortium of members, led the NERC application and oversaw its development through advice from the Programme Manager Chris Hill.
He has been involved in subglacial lakes research for over 15 years and has been to Antarctica twice before, including the Lake Ellsworth site as part of the Chilean expedition in January 2006.
Professor Siegert said: "The two main science questions (is there life in subglacial lakes? Are there climate records within the lake floor sediments), and all the questions that will follow from them, are fundamental and profound. Personally, I feel hugely proud of everyone involved in the consortium - to lead such a programme is a genuine and unique privilege."
Professor Martyn Tranter
Martyn Tranter is Professor of Geography at the Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol
He is leading the part of the subglacial Lake Ellsworth project that will retrieve and analyse water samples from the lake. The water will be tested to see if microbial life is active biogeochemically beneath Antarctica. He will also conduct some simple experiments on the mud on the lake floor to see how chemically reactive it is, and how much solute it can provide to the lake over time. From this, it will be possible to work out how quickly water flows through the lake.
He has been to Antarctica five times, working with the National Science Foundation’s Long Term Ecological Research Program in the McMurdo Dry Valleys where Scott trained prior to his last Antarctic expedition
Professor Tranter said: "This is just about the tops for me scientifically. It would mean the same to me as if Wolves won the Champions League and the Premiership three seasons on the bounce. I’ve been researching glacier meltwater chemistry all my professional life, and I have been predicting life in subglacial lakes for some time, so to be part of the team that actually shows this is the case would be mega."
Professor Jemma Wadham
Jemma Wadham is Professor in Glaciology at the Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol.
She is working with Professor Martyn Tranter on the analysis of water samples from Lake Ellsworth and has been researching how microbial life leaves a fingerprint on subglacial waters.
Previous press releases
- British team embark on ambitious Antarctic mission
5 December 2012
- British team set to embark on ambitious Antarctic mission
7 September 2012
- Engineering team heads to Antarctica to explore hidden lake
11 October 2011
- Exploration of buried Antarctic lake given green light
2 March 2009
- The exploration of Lake Ellsworth: an Antarctic subglacial lake
20 December 2004
- Is there life in lakes under glaciers?
13 October 2003