Learning from extreme events: The wide-ranging consequences of Arctic change
This May, a group of researchers convened a workshop at the Aspen Global Change Institute for an interdisciplinary exploration of Arctic Climate and Weather Extremes. Three of the workshop participants – Heïdi Sevestre, Cecilia Bitz, and workshop co-chair Xiangdong Zhang – shared their perspectives on why this topic matters.
“I’ve never witnessed such extreme weather events. It was the first time that I realized…how bad things could be in that region, how quickly things were changing.”
Dr. Heïdi Sevestre, a glaciologist and member of the Arctic Monitoring and Assessment Program (AMAP) secretariat, recalls a moment in her career when her concept of extreme events in the Arctic moved from intellectual to visceral.
At the end of March 2021, Heïdi and her team trekked onto the ice of Svalbard, an archipelago off the north coast of Norway. They were there to collect snow samples to measure black carbon deposition, part of an effort to understand how air pollution can trigger faster warming of snow and ice. They planned their work for Svalbard’s historically calm spring season, but arrived to find uncharacteristically warm weather. The above-freezing, humid air rapidly translated into unstable storm conditions.
Fast-accumulating snow and winds reaching up to 140km/hr (~90mph) buffeted Heïdi and her team at their campsites and as they skied to collect samples each day. As one storm followed another for two weeks straight, they found themselves burrowing into the snow, burying their tents just to anchor them from blowing away.
“I couldn’t recognize this archipelago that I know like the back of my hands,” Heïdi says, “To see this first-hand was really shocking…. I think people should know about how quickly things are changing in the Arctic. It’s not just the fact that the Arctic is becoming warmer… it’s much more complicated than that.”
“It’s complicated” is a common refrain among researchers studying climate change-driven extreme events in the Arctic. The kaleidoscope of ice, ocean, and atmospheric dynamics shifts continually, with what happens in one system closely intertwined with what happens in another, although precise connections are not always clear. To understand why different events happen, researchers must work across their traditional disciplines and in conjunction with local community knowledge and observations.
The momentum to catalyze collaborative research is urgent because the Arctic is experiencing alarmingly rapid change, and what happens in the Arctic has rippling consequences for nearby communities—and possibly for communities thousands of miles away.
Dr. Xiangdong Zhang, a professor of climate and atmospheric sciences at University of Alaska Fairbanks, seeks to understand how conditions in one place impact conditions elsewhere. His research on atmospheric circulation focuses on how the transport of heat and moisture from lower latitudes impacts Arctic temperature and sea ice. What he sees happening currently is a regime shift:
“We found these new climate states showing increased heat transport going into the Arctic and increased moisture transport going into the Arctic,” Xiangdong says.
In other words, the air moving poleward to the Arctic is warmer and more humid than it used to be. The consequences are increased extreme weather events in the Arctic: strong storms with extraordinary winds, like Heïdi’s team experienced, or rapid melt and break-up of sea ice. In recent years, large masses of sea ice disappeared in a matter of days once the warm season began—a rate of summer melt unheard of 10 or 20 years ago. Astounding in and of themselves, these physical processes also have immediate repercussions for local human (and ecological) communities.
“Larger wind speeds can produce a larger wave surge, wave surges can cause coastal flooding, and also coastal erosion,” Xiangdong explains. These extreme events have life-altering consequences for coastal communities in the Arctic.
Rapid ice loss and changing sea ice rhythms
Rapidly melting sea ice also contributes to the cycle of amplified feedback the Arctic is already experiencing: as ice melts due to a warmer climate, it reveals the darker ocean surface, which absorbs more heat than white, reflective ice, leading to still further warming and ice loss.
Dr. Cecilia Bitz has heard first-hand stories about the consequences of rapid warming and changing sea ice rhythms. A climate scientist, professor, and chair of the Atmospheric Sciences Department and faculty in the Program on Climate Change at University of Washington, Cecilia works closely with the small Arctic community of Kivalina to provide them with sea ice forecasts—predictions of how much ice will be in certain locations in the near term.
Kivalina sits on an upper edge of Alaska, its coast washed by the Chukchi Sea. Transportation by boat and whale hunting are life-sustaining activities in Kivalina. Both rely on just the right amount of opening in the sea ice to succeed, neither too much nor too little. High winds can mean danger for hunters or fishers. Timing of sea ice break-up and formation are also matters of concern on land in Kivalina. Sea ice creates a barrier between eroding waves and the edge of the shore, but only if it forms early enough in the season.
“Arctic cyclones are biggest and most frequent and most intense in fall,” Cecilia says, “And that’s at the end of the ice-free season. So whether the storms come first or the sea ice comes first is super important….It’s really existential for them–they are losing their village.”
“A very humbling experience”
Cecilia sees a two-way exchange of learning around Arctic changes as beneficial to the community in Kivalina and to researchers like herself.
“[They have] great knowledge about Arctic climate change,… and [working with them] ends up being a very humbling experience because they have so much knowledge.”
Meanwhile, community members have expressed to Cecilia that aside from the benefits of having access to regional models, having support from scientists like Cecilia can help amplify their voices outside of Kivalina.
“They said, when we go to the politicians by ourselves, they don’t always listen. But if we bring scientists with us, they listen.”
Cecilia finds this “heartbreaking,” but acknowledges that this dynamic is “basically one of the motivators I have for working with them, even though I’m probably learning more from them than the reverse.”
What happens in the Arctic doesn’t stay in the Arctic
While the communities living in or near the Arctic circle experience the most immediate impacts of local warming, the consequences of climate change at the Pole are far more widespread.
“[The warming Arctic] can change global atmospheric circulation or global weather patterns. That influences the main latitudes, the population, society,” Xiangdong explains.
Weather experienced at lower latitudes can be influenced by what is happening in the Arctic. When Heïdi Sevestre left Svalbard inspired to share the dramatic weather impacts she had seen, she left with a twofold goal: to raise awareness about the challenges facing populations living in the Arctic and to help people living in lower latitudes understand that these shifts impact other regions too, including her home country of France.
“I think it is also our duty as experts, as scientists, to educate populations,” Heïdi says, “to help them understand that everything that we do, for example, in France, can have a positive or a negative impact on the Arctic. And everything that’s happening in the Arctic can have a positive or a negative impact right back at home.”
Xiangdong and Cecilia see climate change research as an opportunity to apply their own self-described “nerdiness” and love of numbers and science to help society. It seems that working to understand one small piece of the climate change problem, perhaps counterintuitively, increases awareness about the big picture, the interconnectedness of Earth’s systems and its societies. Xiangdong describes it this way:
“We are living in this world, right? We want to help increase resilience or reduce risk, reduce the uncertainties in our daily life….I think our work can help that… for society, for other colleagues, and citizens, not only for myself. Because I’m one of the society, one of the citizens.”
Cecilia Bitz shares a similar message, “I think I’m really lucky that I have two major motivating factors for my life’s work, which are: the science is truly exciting and fascinating and the thought that it actually can help us solve the hardest problem I think we will face this century. I feel really fortunate…it’s an honor to be able to do this work.”
The path forward
Having strong motivators will be necessary to continue with this scientific endeavor. Even defining what constitutes an “extreme event” has become a hurdle in a world where the past’s rare events are becoming the future’s “normal.” Other challenges in unpacking the climate mystery of Arctic extremes include: limited funding for research, gaps in scientific understanding of everything from ocean currents to atmospheric oscillations, raising public awareness about climate impacts, and, most concerning, the extremely rapid pace at which major systemic shifts are occurring.
“We don’t have a lot of time left before we’re beyond thresholds that are really, really dangerous….We’re at a crisis already,” says Cecilia.
But this is a struggle these scientists find worth undertaking. All agree that making headway on these urgent and complex questions requires collaboration.
“Each person has their own vision, limited knowledge. So it will be better to learn from a colleague or from other persons,” Xiangdong explains, “Collaboration really helps to improve work, improve knowledge.”
Cecilia provides an example: many scientific models of sea ice conditions rely solely on sea ice temperature and atmospheric response but leave the ocean as an unknown, a “black box” in the representation. However, ocean currents and sea surface temperature also play an important role in sea ice conditions, so bringing oceanographers into the conversation can help to make the models more accurate.
Accurate representation of Earth systems matter because how well changes are characterized impacts how effectively communities are able to adapt. Societal adaptation, in turn, is reliant on political policies and community norms, bringing social sciences and other local knowledge into play as well. At the Arctic Monitoring and Assessment Programme, Heïdi is working at this interface as she and a broader team create a report that aims to provide necessary science to support climate-informed policies and decision making.
“The key today is to, for all of us, I think, be able to learn from each other’s fields of expertise and really open up to these different fields…It’s only by interacting, by making all these fields interact […] that will make changes happen,” Heïdi says, “ I really look forward to learning more about these extremes.”