‘A new Arctic.’ Global warming shifts the North’s entire climate
“The Arctic is dramatically and rapidly changing, and it’s changing so fast and so dramatically that it is transitioning to a new climate.”
That sentence from Dr Laura Landrum summarizes a key conclusion of a new study examining climate change in the circumpolar north, published on Monday in the journal Nature Climate Change.
Landrum and colleague Dr Marika Holland, who co-authored the study, are climate scientists at the National Centre for Atmospheric Research in Colorado.
The pair told Cabin Radio their findings confirm realities many northerners already recognize on a daily basis.
Laura Landrum, left, and Marika Holland.
“Everybody knows that [the Arctic climate] is changing and experiencing new conditions,” said Landrum, “but what we wanted to … quantify is whether or not that climate has entered a new regime.”
Using 249 climate simulations from 1950 and 2100 based on available data, the two measured existing and projected changes in sea-ice concentrations, air temperatures, and the type of precipitation (rain versus snow) the Arctic receives throughout the year.
“One of the things that makes the Arctic unique is its frozen state,” said Holland, “the fact that you have a lot of frozen precipitation, you have a lot of sea ice on the ocean, you have air temperatures that promote freezing conditions.
“So that was why we picked those three indicators: they reflected this frozen state of the Arctic, and that we’re transitioning away from this frozen Arctic into this new climate state.”
Instead of a northern landscape defined by ice and snow, the new Arctic normal will become open waters and rain, the study projects.
These changes will make it harder for scientists to predict what’s coming next, and for communities to adjust to the potential fallout.
Landrum used an analogy to explain the implications.
“If you are a sports fan and you have your favourite baseball team, and you go to their games a lot – and suddenly it’s a whole new team – then you’re going to be like, ‘Oh, what am I going to expect from this game?’” she said.
Less ice, warmer water, more rain
Sea ice demonstrated the most significant shift of the three indicators. Temperature and precipitation are transitioning more slowly, Landrum and Holland’s said, but they are nonetheless shifting.
What’s more, each indicator can directly affect the others.
A graph from the National Centre of Atmospheric Research outlines annual change within the three indicators of sea ice, temperature, and precipitation. Simmi Sinha/UCAR
Less sea ice means more exposed water for sunlight to hit, warming the water faster. This in turn makes the temperature of the air warmer, which can cause it to rain later in the year instead of snowing.
“The timing of the emergence of these new climates is what we sort-of expected,” said Landrum. “They’re all interrelated.”
The impacts these changes can have on those living in the North are wide-ranging.
For example, it can make life on the land harder.
“Sea ice is often used as a platform for travel, for transportation, for access to hunting seals and whales,” Landrum said. “And as you change that … you are changing access and availability for food.”
“This is [an] area where we work with others to try to understand these impacts, because we’re not biologists,” Holland continued, “but there are lots of implications of these changes in the sea ice, these changes in rain or snow, on the biology in the region.”
‘Do something now’
Despite these shifts, Landrum said the Arctic is not necessarily passing a point of no return where humans can no longer affect the changing climate.
“The sea ice has already changed dramatically. That doesn’t mean we can’t have an impact on how much more it will change,” she said.
“I don’t think we’re at a tipping point that means nothing we can do can have an impact.”
Holland said cutting fossil-fuel emissions is a much-needed step.
“If we collectively reduced the burning of fossil fuels, we would not face as dire consequences in the Arctic or the globe as a whole,” she said. “We can see that in our science.
“We can do something and we should be doing it quickly. In order to make an impact, we need to be doing things now.”
Landrum agreed. “Our climate change is now. It’s here, it’s dramatic, it’s impactful,” she said.
“And it would be great if, collectively, we can do something now.”