The region, which sits at the northernmost point of the globe, is a unique ecosystem characterized by areas of permanent snow and ice. But, if the Earth continues to face damaging levels of emissions, the Arctic could see "summer days with practically no sea ice as early as the next couple of years," a new peer-reviewed study out of the University of Colorado Boulder revealed.
"The first ice-free day in the Arctic could occur over 10 years earlier than previous projections," the study, that was published Tuesday, added.
What is an ice-free day?
To scientists, an ice-free day does not mean there is absolutely no ice in the water. Instead, the term is measured by the quantity of ice in the water below a certain threshold.
According to researchers, the ocean is ice-free when it has less than 1 million square kilometers, or 386,000 square miles, of ice. That number represents less than 20% of the region's minimum ice cover in the 1980s.
When will the Arctic be ice-free?
"The first ice-free day in the Arctic could occur over 10 years earlier than previous projections," the study found.
Researchers predict that the first ice-free day will take place on a late August or early September day between the 2020s and 2030s under all emissions scenarios.
By the middle of this century, scientists say it's likely the Arctic will have an ocean without floating ice for a whole month, during a September — when the region experiences its lowest amount of ice coverage.
By the end of the century, the ice-free season could span several months in a year, even in winter months if high emissions become the norm.
What is causing sea ice loss?
Greenhouse gasses, according to study researcher Alexandra Jahn, associate professor of atmospheric and oceanic sciences at CU Boulder.
When snow and ice cover decrease, the heat absorbed from the sun by the ocean increases. As a result, ice melt and warming in the Arctic gets worse.
What happens if the Arctic loses its ice?
The loss of sea ice can disrupt the Arctic ecosystem in a number of ways, the study outlines.
Arctic animals, like polar bears and seals, could face challenges as they rely on ice for their survival. Additionally, non-native fish of invasive species may migrate to the warmer waters, having an impact on Arctic sea life.
The warming of water could also pose a threat to human communities living near the coastal region — as the ice melts and ocean waves grow larger, the coast could see dangerous erosion.
Can the loss of sea ice be prevented?
Scientists do say there is hope for preserving the Arctic for as long as possible.
"Even if ice-free conditions are unavoidable, we still need to keep our emissions as low as possible to avoid prolonged ice-free conditions," Jahn said.
If things continue as is, with intermediate emissions, the Arctic may only become ice-free for a few months, from August to October, researchers found. But, if things shift to the highest emissions scenario, the Arctic could be ice-free for up to nine months late this century.
"This would transform the Arctic into a completely different environment," Jahn said, "From a white summer Arctic to a blue Arctic."
The study also notes that "the Arctic is resilient and can return quickly if the atmosphere cools down."
Source: www.cbsnews.com
No comments:
Post a Comment