[Vishnu Nandan is a radar remote sensing expert on Arctic and Antarctic sea ice, and a post-doctoral researcher at the Centre for Earth Observation Science (CEOS) at the University of Manitoba, Canada. He lived out of the German research icebreaker R/V Polarstern as part of theMOSAiC International Arctic Drift Expedition – one of the biggest scientific expeditions to the Central Arctic Ocean.]
Nature India: You are finally back home after four months of being locked down in the Arctic darkness. What was it like?
Vishnu Nandan: I have undertaken more than 15 expeditions to the polar regions but this one had its own challenges. We were in the middle of frozen ocean enveloped by complete darkness for 80 days, temperatures plummeting down to -55°C with wind chill and sometimes stormy weather.
Working with small metallic nuts, bolts and screws under extreme cold required a lot of effort. When we reached Polarstern on 13 December 2019 on the Russian ice breaker Kapitan Dranitsyn, I was anxious. We did not want the ice to break up with two ships standing next to each other. Towards the end of February 2020, sometimes the skies were clear and sometimes illuminated by the full moon with Venus in its precincts.
From 3 December 2019 until the end of February 2020, we had close to 80 days of complete darkness. Thereafter we experienced few days with nautical, astronomical and civil twilight. At one point, darkness becomes a way of life for me. Now after returning home, I miss the darkness. I would say that such prolonged periods of darkness have their own beautiful flavour.
NI: Was there any threat from the novel coronavirus that gripped the rest of the world? How did you handle that?
VN: With the COVID-19 crisis, there was a lot of uncertainty about our returning home. Our whole group was in isolation from the outside world for many months and we did not have a clue about the seriousness of this situation.
With all countries closing their borders on us, we were worried about our safe return home. At one point, I was even ready to stay back for the next leg, until May or June.
But then we were allowed to get back home to our families while following all protocols.
NI: What is the main objective of the MOSAiC expedition and how is it different from the previous Arctic expeditions?
VN: The primary goal of the MOSAiC expedition is to investigate the principal components of the Arctic climate system -- the atmosphere, sea ice, ocean, ecology and biogeochemistry. The focus is on Arctic as the epicenter of global warming and to gain fundamental insights key to better understand global climate change. The previous Arctic expeditions focused on specific time periods for a few months. The data collected from the MOSAiC expedition will cover all seasons (annually) and a large area (as the Polarstern moves with the sea ice).
As many as 300 scientists will be on board Polarstern, rotated in 6 different legs. I was on leg 2. Scientists from 20 nations are participating on and off board Polarstern.
NI: What is the focus of your work? How are you going to take this forward?
VN: I am a sea ice scientist, specialised in radar remote sensing. My expertise has always been in using satellite- and ground-based radar remote sensing data to improve the accuracy of critical snow and sea ice parameters such as snow depth sea ice thickness, freeze- and melt-onset (i.e. when sea ice starts forming and melting).
For MOSAiC, my research work focused on deploying radar sensors on ice, operating at multiple radar frequencies, to improve the accuracy of retrievals of above mentioned parameters, which will ultimately help the radar satellites to provide improved and accurate estimates.
NI: Why are such scientific experiments needed to understand global climate?
VN: Although scientists conduct yearly field-based experiments in the Arctic for studying and answering unresolved questions about our planet, all these experiments are short termed. They don't fully capture long-term changes over large areas. MOSAiC is unique. Polarstern is anchored on to a sea ice piece. As she moves along with this piece, propelled by the transpolar drift for one whole year, we will be able to measure critical parameters along the whole corridor, which covers a lot of area.
Between the beginning and end of our leg, we had drifted a meandering distance of 675 km, and close to 410 km straight line distance.
These parameters from our measurements will help us improve climate models which help us accurately predict weather, monsoon timing in countries like India and extreme events such as cyclones and flash floods.
We had 64 scientists on board from 12 nationalities. I was the only Indian national on board, representing Canada.
NI: What were the working challenges you faced?
VN: Sometimes we had to troubleshoot and repair instruments on the ice. Some of the instruments were not meant for operating under extreme conditions. So we had to improvise. Refurbishing instruments under such conditions was extremely challenging. We even had to work with an instrument which stood 15 ft tall and weighed close to 300 kg.
NI: What kind of communication channels did you have? What did you do for entertainment?
VN: We were lucky to have WhatsApp access on board, with restrictions (only text, no pictures or videos). We had a gym, swimming pool and sauna. We celebrated many birthdays, including mine., celebrated the northernmost Christmas and the New Year. We saw movies, played board games and organised camping trips, where we setup tents. Besides, every Wednesday evening, we went group skiing and hiking on the ice.
NI: What was the first thing you did after returning home to a world gripped with the novel coronavirus scare?
VN: The first thing I did was to eat a sumptuous meal made by my wife. Currently, I am following the Canadian rule of 14-day mandatory self-isolation.