n September 20, 2019, the Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition, led by the German icebreaker research vessel Polarstern and escorted by the Russian icebreaker Akademik Fedorov, departed from the Norwegian port of Tromsø, sailing for the Central Arctic Ocean. The year-long expedition, which will see the Polarstern anchored to a drifting ice floe, will move with the current across the Arctic Ocean. Thelargest polar expedition in history, MOSAiC is an international program involving a rotating team of 600 experts from 17 countries.
At the expedition’s launch, Markus Rex from the Alfred Wegener Institute, Germany and chief scientist of MOSAiC, said that the Arctic is the epicenter of global climate warming and it has already undergone dramatic changes. “For the first time we will be able to measure the climate processes in the Central Arctic in winter. And so for the first time, we will be able to understand this region and correctly represent it in climate models,” Rex said.
Scientific research indicates that the Arctic has warmed at twice the speed of the rest of the globe, resulting in the rapid loss of sea ice. The data gathered will be crucial to study changes in the Arctic climate and its role at the global scale, and the impacts on the weather and climate in high- or mid-latitudes.
Eighteen Chinese scientists are scheduled to participate in different legs of MOSAiC. Among them are 12 researchers from organizations including the Polar Research Institute of China, the First and Second Institute of Oceanography of Ministry of Natural Resources, the Ocean University of China, Zhejiang University, Beijing Normal University and the Taiyuan University of Technology, who had already completed their part of the expedition by early January 2020. During this time, the Polarstern along with the ice floe on which the research was being carried out, had drifted 200 kilometers toward the North Pole.
Lei Ruibo, a sea ice physicist from the Polar Research Institute of China told NewsChina they had witnessed the aurora borealis, better known as the Northern Lights, experienced the polar night, seen a giant blazing moon, encountered potential threats from polar bears and dealt with harsh weather, equipment failure, lack of fresh food and homesickness. Some scientists, including Lei, suffered severe frostbite.
In late January, NewsChina interviewed Lei by telephone after his return about the progress of the expedition. After being part of expeditions in the Arctic and Antarctic during the past decade, this time, he was appointed MOSAiC coordinator for the Chinese team.
NewsChina: What is the goal of the project and what is the significance of the main research compared with previous studies in the Arctic?
Lei Ruibo: The goal of MOSAiC is to gain urgently needed in-situ data on the interactions between the atmosphere, ocean and sea ice, as well as on the ecosystem, so as to better understand changes in the Arctic climate and its role at the global scale.
Although there have been a few similar year-long ice drift expeditions to study the Arctic, the most recent in the late 1990s, sea ice conditions have changed significantly during the past two decades. Data collected earlier can no longer fill the gap of knowledge for our present understanding of the sea ice, and we are unable to describe the physical changes in the sea ice that have occurred along with the process of climate change in recent decades. The main objective is to gather data on five disciplines, including the atmosphere, sea ice, ocean, ecosystems and biogeochemistry, to enhance understanding of the interactions of various components of the climate system. With the most advanced monitoring technology and equipment, as well as professional experts on Arctic science across the world having joined the expedition, it will provide the most comprehensive opportunity to better learn about the Arctic.
NC: What’s the focus of your work this time and can you share with us the interaction of the sub-area you work on with other disciplines?
LRB: My focus is on sea ice physics, or the processes of ice cover evolution, in the polar region, and development of sea ice observatory technology and equipment. Based on studies on the changes in sea ice and atmosphere-sea and ice-ocean interactions in the Arctic, we want to reveal the impact and feedback of sea ice on climate change. A warming climate can affect the formation and seasonality of sea ice, while changes in sea ice can further affect marine ecology.
Studying sea ice physics helps us understand the circulation of greenhouse gases including CO2 and methane between the atmosphere, snow, sea ice and oceans.
To be more specific, through deployment of buoys on sea ice, one of the objectives is to study the annual cycles of sea ice thermodynamics, kinematics [motion] and dynamic deformation, as well as their responses to atmospheric forcing, for example, heavy storms.
The sub-areas that researchers are investigating are closely linked despite the differences in knowledge and theoretical backgrounds of the scientists in different fields. For example, for the same sample of an ice core, physicists focus on the physical structure of the ice core to depict the impact of climate change on the formation of the ice, while biologists focus on the microorganisms contained in the ice and study the impact on such organisms under climate warming. Scientists focusing on geochemical circulation study the existence of greenhouse gases contained within the ice to explain the gas exchanges between atmosphere and ocean through the snow and ice. All these achievements, once combined, can thoroughly explain the interactions that influence the climate system and life in the Central Arctic.
NC: What are the challenges involved in this type of fieldwork?
LRB: The whole process was not easy right from the start. It really took us a long time to find ice thick enough for our main ice camp since the region is dominated by thin first-year sea ice of less than one meter thick. The two primary dangers are encountering polar bears and storms. Due to the polar night, without sunlight, it is challenging for even professional polar bear guards to spot them using lights from the ship when there is only limited vision.
Since late September, we saw polar bears a few times, including sightings of lone bears and of mother bears with cubs, but fortunately, they were not very close and nothing dramatic happened. When researchers go on to the ice floe to work, a guard accompanies them. If a bear is spotted, the team must immediately return to the ship. If escape is impossible and the bear is within 30 meters, a flare gun will be used to scare it away.
Another challenge for our work, more than bear visits, is the powerful winter storms. We had projected that sea ice would be more stable in winter, but in reality it was not. Normally, scientists can work if the wind speed is lower than 17 meters per second. Apart from delaying work, when a storm sweeps over the ice, it can tear new fractures or cracks across the ice floe, destroy ice-based instruments, and the resulting rescue and repairs mean extra days of work. For example, a huge storm in mid-November caused a 30-meter-high meteorological mast in the Central Observatory of our main ice station to fall down.
NC: How do the scientists cope with such hostile working conditions?
LRB: Considering the heavy investment from participating countries, it is of paramount importance for scientists to maintain the safety of our monitoring instruments. Of course, we also need to cope with other normal challenges like no sunlight, extreme low temperatures and a long time away from our families. Following the German organizer’s instructions, we underwent rigorous preparatory training programs before the expedition including firefighting, drills in case we need to abandon ship, measures to escape if you fall into the frigid water and how to deal with polar bear attacks.
For a polar bear attack, we were told to try not to run, or at least not to run in a straight line. That’s because if polar bears, due to their heavy weight, run and try to turn at the same time, they can easily fall over, thus allowing extra time for people to escape.
This time, apart from expedition participants undergoing survival or other specialized training, thanks to the full preparations of the German organizer, eight professional polar bear guards were employed to ensure our safety. Most of them are professional explorers or hunters from Arctic countries who can deal with polar bear attacks. But for most of the scientific activities at the individual measurement sites on the ice floe, we still need to rely on self-protection awareness and individual safety measures.
NC: What are the new findings so far, and what’s the plan to share the data?
LRB: Despite the extremely challenging conditions, we have tried to maintain a steady flow of scientific data in all disciplines. However, so far it is not quantifiable since there are still five more legs to go. There is one common understanding during the winter expedition so far among scientists. Contrary to our previous understanding that there are relatively weak dynamics of sea ice in the Arctic during winter, [meaning it was not expected to move much], the ice is unusually thin with most of it less than one meter thick. This results in it being highly dynamic and unstable, especially during storms. This also posed extreme difficulties in choosing an ice floe thick enough to build the ice stations.
This was the first time I went on a winter expedition in the Arctic. Previous research found that the frequency of extreme high temperatures is increasing in the Arctic in winter, which even resulted in random sleet when the air temperature increased to near zero C. In the first leg of the expedition I took part in, the temperature was overall normal, with a high of -4ºC and a low of -34ºC.
We have a data sharing platform and the data collected from this expedition will ultimately be a common legacy for all human society. For the first step, researchers participating and contributing to this expedition can get real-time data through the shared platform. All the data will be available to the public by 2023 after it’s checked. Scientific analysis and climate modeling, once completed, will provide evidence to renew public perception on the overall condition of planetary climate change.
NC: Why is this project so unique? Can you give us some details about the timeframe and people involved?
LRB: The MOSAiC expedition is not the first to attempt an ice drift. Apart from a Norwegian explorer’s pioneering three-year drift fieldwork in the late 1800s [Fridtjof Nansen froze his ship Fram into the Arctic ice to attempt to reach the North Pole], Soviet and Russian scientists also established research bases on drifting ice floes, starting in the late 1930s. But operations to establish drift research stations were stopped [by Russia] in 2013 due to the heightened danger of the unstable thin ice in recent winters.
There are six legs for the whole expedition from late September 2019 until late October 2020. As planned, 18 Chinese researchers from all five sub-areas including ocean, sea ice, ecosystems, atmosphere and biogeochemistry will join five of the six legs. By December 13, after exchanging scientists and crew members, the first leg of the project in which I participated was successfully fulfilled. Professor Liu Hailong, a physical oceanographer from Shanghai Jiao Tong University joined the second leg to continue the work, along with more than 60 scientists from across the world.
NC: What is China’s role in the project and current achievements in Arctic research?
LRB: Apart from Germany, the US is a big contributor to the project, due to their existing expertise in Arctic studies. China, Sweden and Russia also play important contributing roles. The expedition is being carried out mainly by German icebreaker the Polarstern, and four additional icebreakers from Sweden, China and Russia are scheduled to help transfer people and supplies to and from the MOSAiC ice camp throughout the year. China’s new polar research vessel Xuelong 2 will carry scientists and supplies between the fifth and sixth legs in August 2020.
The whole MOSAiC drift program is composed of one Central Observatory, three large sites, eight medium sites and some 50 position note sites, a total number of more than 60 observatories in a 40-kilometer radius around the Polarstern. During the first leg, China contributed instruments for the construction of the distributed observatory network by deploying one uncrewed ice station, five oceanic profilers, 16 sea ice mass balance buoys and 20 ice drifters. Most of the buoys were designed and built in China.
Through international cooperation, we will collect data from all the observatories, which will definitely promote dynamic and thermodynamic studies on Arctic sea ice and improve the weather and sea ice forecasting in the Arctic region.
China’s first national Arctic expedition was implemented in 1999 and there���ve been 10 up to now, but none in winter. Prior to 1999, some Chinese scientists had taken part in Arctic expeditions organized by other countries. China did not have an expedition icebreaker vessel until 1993 when it bought the Xuelong from Ukraine and upgraded it into a polar research vessel. Before 2008, China had only conducted Arctic expeditions in 1999 and 2003. Since 2008, also the fourth International Polar Year, we’ve done biannual expeditions in the Arctic area, and from 2018, the expeditions will be an annual scientific undertaking. In July 2019, China’s first self-built polar ice-breaker the Xuelong 2 was launched to boost China’s polar research and expedition capabilities. With additional funding in the future, we expect more expeditions in the autumn and winter seasons.
NC: Any personal achievements so far from the expedition that you can share and will there be such joint research expeditions in the future?
LRB: My research which focuses on monitoring the changes in the sea ice can be obtained mainly through data collected from the deployed buoys during the first leg of the expedition that I joined. More buoys have been deployed than my previous expeditions to the Arctic because of the strong logistics support capability of MOSAiC and so far the survival rate of these buoys is relatively high. More importantly, the buoy distributed network can be maintained throughout the whole year, and more buoys can be deployed in the coming legs through cooperation with the scientists from other countries, ensuring high-quality data can be collected continuously.
Although international cooperation on Arctic research has been going on a long time, and data sharing is commonly practiced among international scientists in this field, there’s never been an expedition of such a scale with this level of logistical support before. Financial investment for this voyage from participating countries is unprecedented. The logistics budget for the expedition is roughly 140 million euros. So I can’t really say whether there will be similar large expeditions often, but there will certainly continue to be joint studies on climate change and the Arctic. MOSAiC provides an outstanding example for people to study the Arctic climate together.