Waves in the Arctic Ocean are now reaching up to 16 feet in height, marking the first time such large waves have been spotted in the far northern regions of the world. Some investigators believe rising global temperatures may be the underlying cause behind the oversized waves.
The Arctic Ocean is usually covered in ice, but greater seasonal thawing is now occurring every summer, exposing water to the air over parts of the waterway. Historically, Arctic ice retreats less than 100 miles from shore during the warmest times of the year. The frozen surface receded by over 1,000 miles in 2012. Environmentalists estimate the entire ocean will be exposed to air by the middle of the 21st Century.
University of Washington researchers discovered the massive waves during an Arctic storm that took place in September 2012.
Additional energy added to the water by rising temperatures can increase the frequency and intensity of waves. The ocean water also makes it possible for high winds, fueled by higher temperatures, to raise the surface of the ocean, creating waves. Large waves start as small ripples, which are pushed by wind. They grow as they travel through the water, and more open water provides the opportunity for the waves to travel greater distances than before, creating larger waves.
Waves can break apart ice floes and sheets, leading to greater areas of water exposed to wind. This, in turn, could lead to more powerful waves, creating a feedback loop that could exacerbate loss of ice cover.
"The melting has been going on for decades. What we're talking about with the waves is potentially a new process, a mechanical process, in which the waves can push and pull and crash to break up the ice," Jim Thomson, an oceanographer with the UW Applied Physics Laboratory, said.
Study of the actions of waves on ice in the Arctic can assist researchers studying the effects of climate change in the Arctic. This could help answer questions about how quickly water is becoming exposed to the air and wind, and how that could affect future melting.
Oil companies are closely watching melting ice in the Arctic. Shipping lanes - and costs - could be significantly reduced by bringing tankers near the North Pole, compared to east-west routes. Significant waves could significantly impact these plans.
Jim Thomson will follow up this study by placing sensors tin the frigid waters to record how waves are affected by seasonal changes.
Investigation of house-sized waves in the Arctic Ocean was detailed in the journal Geophysical Research Letters.
