A graph showing the globe’s rapidly diminishing sea ice went viral last week. Now a new study warns that the Arctic melt could trigger “tipping points” that speed up global warming around the world. A spokesperson for the World Meteorological Organisation tells the New Statesman: “We are entering a new climate era.”
So what exactly is going on and what degree of doom does this spell for the rest of us?
I ask Professor Julian Dowdeswell, a glaciologist and director of the Scott Polar Research Institute at Cambridge University, if the new data from the Arctic means we’ll be seeing a The Day After Tomorrow style Gulf Stream shutdown any time soon?
“No,” he replies. Crashing helicopters and flash-freezing are still the stuff of “scientific nonsense”.
But he also points out that the film’s opening scene, showing the break-up of an Antarctic ice-shelf, has already happened. And that at least 70-80 per cent of the changes we’re seeing now are human-induced.
Such changes include: extremely high temperatures in the arctic regions (as much as 20°C higher than normal for the time of year); an Arctic sea ice winter maximum that was the lowest ever in March; and a decline in summer sea ice from around 8m sq km to about 4.5–5m sq km over the last 30 odd years.
So while there may still be spikes in sea ice levels in any given year, the long-term trend of the satellite data is clear: Arctic sea ice is in an alarming decline.
As for what this means for the UK’s weather, scientists still cannot say with certainty. One possible scenario would be a slowing of the Gulf Stream and paradoxically cooler conditions in the UK.
When winter sea ice is formed, Dowdeswell explains, it leaves behind a lot of the water’s salt. The remaining water therefore becomes very salty and very dense, and sinks to the bottom of the water column, where it flows south. In its place, you get less dense, warmer, water returning back north.
So theoretically, if you produce less sea ice you slow the circulation of the Gulf Stream: “In principle, if that goes far enough, you could actually end up with a cooler Britain in a warming world,” says Dowdeswell.
For the Arctic community
According to Clare Nullis, a media officer with WMO, “The most immediate human impacts of the changes in the Arctic are people who live there and see their traditional way of life being threatened.” Populations in Canada and Alaska are already moving in order to avoid falling into the sea. The timing and location of hunting practices are changing. And disease risk is on the rise.
Some point out that increased opportunities for shipping and tourism will bring the region economic benefits. But it will also raise the risk of oil and chemical spills.
For the rest of the world
As the new Arctic Resilience Report finds, the effects of Arctic warming are already being felt as far away as the Indian Ocean.
And, as a spokesperson from WMO’s World Climate Research Programme, points out, the trend is likely to increase: “Less sea ice means less sunlight reflected into space and more absorbed by the oceans, so the temperature of the Arcitc (and the world) increases… an example of what we call positive feedback.”
With 2016 on track to be the hottest year on record, further melting of the world’s glacier and ice caps looks assured. As for more geographically specific predictions, scientists are still wary of saying for certain. According to Mark Serreze, director of the National Snow and Ice Data Center in America,
“There is a strong debate ongoing in the science community regarding how a warming Arctic might influence weather patterns in the middle latitudes. Some scientists argue that we are already seeing some of these effects – things like stuck weather patterns whereby Chicago is in a deep freeze while at the same time Alaska is seeing extreme warmth. Other scientists maintain that while the warming Arctic may have some influence, this is overwhelmed by things like El Nino.”
What is certain is that the recent election of Donald Trump has destabilised the global move to combat climate change and will make the need for joined-up scientific argument and research greater than ever.
Sadly his plans to remove the budget for climate change science, through Nasa research, means that we could all be seeing a lot more hot water ahead.This article is from the CityMetric archive: some formatting and images may not be present.