A N-ICE trip to the North Pole: Understanding the link between sea ice and climate

Imagine. It’s the bitter Arctic winter, it’s dark, cold enough to kill, and your ship is stuck in sea-ice. There’s nothing you can do against the heave of the ice, except let your ship drift along. Out of your control. This seems like a difficult prospect today, but then imagine it happening over a century ago.

This is exactly what did happen when Norwegian explorer, Fridtjof Nansen, intentionally trapped his ship, Fram, in Arctic sea-ice in 1893 in an attempt to reach the North Pole. For about three years, Fram drifted with the ice until finally reaching the North Atlantic. Whilst a main motivation for their extraordinary journey was to find the Pole, they also made a number of scientific observations that had a profound influence on the (at the time) young discipline of oceanography.

Scientists led by the Norwegian Polar Institute (NPI) are now – pretty much on the 120th anniversary of the original expedition – repeating the journey, this time purely in the name of science. I’m a member of the international team, meaning that the University of Bristol gets to play its part.

View from near the Norwegian Polar Institute, Tromsø, at about
2.30pm in the afternoon! Tromsø is on a small island,
surrounded by beautiful mountains, but has very long, dark winters.

The group I’m working with are investigating the role of newly formed sea-ice and freshwater on the flow of heat and nutrients through Arctic oceans, which plays a key role in regulating climate both locally and on a global scale. The sea-ice in the Arctic is diminishing at an alarming rate, with between 9.4 and 13.6% decline per decade in the perennial sea-ice from 1979 to 2012 according to the last Intergovernmental Panel on Climate Change report [1]. If we are to understand how the sea-ice might change in the future, and what impact this might have on other systems, we have to be able to understand the physics of the system today.

Lance during a scientific cruise in Svalbard.
Photo: Paul Dodd / Norwegian Polar Institute

My role is to help to chemically analyse the seawater, in order to trace the freshwater input to the oceans. The amount of freshwater will determine the density of the water, and so will control the degree of stratification or sinking, which will be important for the transport of heat.

In November, I went to visit the Norwegian Polar Institute in Tromsø in the very north of Norway for a pre-cruise workshop. I got to meet a number of the Norwegian Young Sea-Ice (N-ICE2015) team, and visit Norway – a place I’d never been before as Antarctica is my usual stomping ground! We had two days of learning about the scientific interests of all the group members, and finding our way around some of the high-tech instrumentation that we will have at our disposal. I also got a tour of the ship that N-ICE2015 will use: the R/V Lance. By the end, everyone was keen to set off – although everyone will now have to wait until January…

This blog is written by Cabot Institute member Kate Hendry, Earth Sciences, University of Bristol.

Kate Hendry

Further information

You can find out more about N-ICE2015 at the project website.

[1] Climate Change 2013: The Physical Science Basis. Working Group 1 Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, 2013.

Converting probabilities between time-intervals

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1-in-200 year events

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Before pursuing an MSc in Climate Change Science and Policy at the University of Bristol, I completed my undergraduate studies in Environmental Science at the University of Colombo, Sri Lanka. During my final year I carried out a research project that explored the impact of extreme weather events on coconut productivity across the three climatic zones of Sri Lanka. A few months ago, I managed to get a paper published and I thought it would be a good idea to share my findings on this platform. Climate change and crop productivity There has been a growing concern about the impact of extreme weather events on crop production across the globe, Sri Lanka being no exception. Coconut is becoming a rare commodity in the country, due to several reasons including the changing climate. The price hike in coconuts over the last few years is a good indication of how climate change is affecting coconut productivity across the country. Most coconut trees are no longer bearing fruits and thos

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