Frozen Frontier: Climate Change Attracting Global Economy To Arctic
In a couple weeks as we hang up our winter jackets to welcome the warmth of spring, ice that has formed over the Arctic Ocean and Hudson’s Bay will be covering the largest area that it will reach in 2019. This is known as the annual maximum sea ice extent, which occurs at the very end of our winter.
Following this, as the sun grows more intense over northern latitudes and temperatures begin to rise, the sea ice will begin its usual 6-month retreat poleward until September, when temperatures reverse – only this process is becoming increasingly unusual. This year the maximum sea ice extent is on track to be one of the smallest since satellite records began 40 years ago, in 1979. On March 4th, the National Snow and Ice Data Center (NSIDC) released the data finding that February 2019 was the 7th lowest February extent ever recorded. For the climate scientists at the NSIDC and elsewhere, this is hardly surprising. The 10 lowest maxima have all occurred since 2005, with the 4 lowest having all occurred in the last 4 years.
It has been known for years that contemporary climate change driven by human-generated greenhouse-gas emissions, predominately via the burning of fossil fuels, has been warming the Arctic at a rate 2 to 3 times faster than the global average, leading to sustained sea ice loss. The average projection from dozens of global climate models indicate that we are likely to see an ice-free Arctic summer in some year between 2070-2100. However, the observed melting has proceeded significantly faster than these models have predicted. Not only is less area covered by ice, but what remains is much thinner and younger. Between 1978 and 2012, the volume of multi-year ice declined by over 75% and the oldest and thickest ice, 5 or more years old, declined by 95%. This means that an increasing portion of Arctic waters are only frozen over during winter months, with the ice being much thinner. Recent studies aimed at correcting the gap between prediction and observation have found that an ice-free summer is much closer than previously thought – possibly as early as 2028, and by 2050 with very high confidence. We are likely only a couple decades away from having open ocean over the North Pole for the first summer in at least 44 000 years.
So what? It is hardly an unpopular opinion that cold and icy winters are a downer anyways. Yet in the next 30 years the Arctic system will change fundamentally, with far-reaching environmental and human impacts. The ice caps are crucial for maintaining the stability of ecosystems, human societies, and our global climate patterns. The loss of sea ice is already impacting delicate Arctic ecosystems as many species are increasingly threatened with extinction. While narwhals and polar bears are the popular face of endangered wildlife, unseen zooplankton that form the basis of the Arctic food web are under threat due to decreasing ice, the bottom of which provides habitat for their food source: algae. Thus, the disruption of algae growth has implications for nearly every creature in the region, especially fish and whales.
Read full article . . .