While scientists who study climate change know that humans are having an impact on the planet, and that the Arctic is rapidly warming faster than the rest of the planet and losing its sea ice, they’ve had a hard time figuring out some of the connection between warming and sea ice melt.
But researchers may have found out how much melting is due to humans, and how much is due to natural cycles, according to a new study in Nature Climate Change. The researchers determined that about 30 percent to 50 percent of ice melt is due to natural cycles, but the remaining melt is due to human activity.
This is important because it will help researchers predict if and when all of the Arctic sea ice may melt by.
Additionally, part of the reason the Arctic is warming so quickly is that as the ice and snow melt, the surface is less reflective, meaning it absorbs more heat, and that compounds the heating, in turn making it happen more quickly.
They were able to discover what was causing the melt by using computer models that use observed data from years past to predict future patterns and outcomes. This helped them come to the conclusion that, “ Internal variability dominates the Arctic summer circulation trend and may be responsible for about 30–50% of the overall decline in September sea ice since 1979.”