What is the coolest thing in Antarctica? Hot-water drilling ! Because once the hole is finished, there is time to celebrate with style. But let me tell you more about it.
Bruce and I share a common love for digging in the snow. But even the keenest of snow diggers won’t get much deeper than a couple of meters below the surface. How can we get even deeper and all the way through the hundreds of meters of ice beneath our feet ?
We use hot water to drill a hole through the floating ice to gain access to the ocean underneath. Once the hole is finished we drop a sediment corer down through the hole, and pull an approximately 1.5 m long sediment core from the ocean floor. The core tells us when exactly the grounding line has retreated at this location – because sediments floating in the ocean waters can only settle if there is no ice. After we have pulled the core, we use two cameras that look up and downwards to film layers within our borehole and especially how the underside of the ice shelf looks like. Are there any rocks frozen into the ice (upward looking camera)? Or are there flourishing ecosystems on the ocean floor as described by Jules Verne’s science-fiction novel ‘10000 leagues under the sea’ (downward looking camera)? In our final step, we then deploy oceanic instruments through the hole to measure water temperature/salinity and the strength of the current. Additionally a series of thermistors are placed into the hole – all while racing against the time until the hole freezes again. So how long does it take to drill a hole?
Martin and Dale as the drilling specialists in our team say “it takes us about 2 days to prepare the drill, then 1 day to melt the snow for the drilling water, and once we have started drilling about 5 hours for a 400 m deep hole.” But then there is the magic moment when they melt their way through the last inch of ice and the hot water in the borehole escapes into the ocean cavity underneath. “We then have about 24 hours to do all the experiments before the hole freezes again.” I’m impressed, this means that they don’t get any proper sleep in several days ! Absolute heroes… So what do you do after everything is finished? “Well, there is still a lot of hot water left in our tanks – so we soak in the hot tub and enjoy the view.” I seriously can’t think of anything cooler than sitting in a hot tub on a glacier in Antarctica !