Arctic hurricanes are a force to be reckoned with

Posted by Flora Malein

New research suggests arctic hurricanes should be included in climate models.

Although we may be more familiar with their tropical counterparts, arctic hurricanes or ‘polar lows’ are polar storms that occur complete with hurricane eye and 30 foot waves that can sink small ships. A new study by scientists suggests that these arctic hurricanes are far more important to the functioning of our climate than previously thought.  
 
Geoscientists Alan Condron and Ian Renfrew found that polar cyclones have a significant impact on ocean circulation and climate but are not included in any current climate models. They are important as they influence the ‘conveyer belt’ current that drives ocean circulation in the Northern hemisphere, known as the thermohaline circulation.
 
"Before polar lows were first seen by satellites, sailors frequently returned from the Arctic seas with stories of encounters with fierce storms that seemed to appear out of nowhere," says Condron, a physical oceanographer at the University of Massachusetts Amherst.
 
"Because of their small size, these storms were often missing from their weather charts, but they are still capable of producing hurricane-force winds and waves over 11 meters high (36 feet)." 
 
As current climate models are missing these localised, but powerful storms, Condron and Renfrew believe that current models making predictions about our future climate could be inaccurate. 
 
"The fact that climate models are not simulating these storms is a real problem," adds Condron.
 
"Because these models will wrongly predict how much heat is being moving northward towards the poles. This will make it very difficult to reliably predict how the climate of Europe and North America will change in the near future."
 
In a paper published in the Letters sections of Nature’s Geoscience journal, Condron and Renfrew describe a new, state-of-the-art climate model that simulates the high wind speeds associated with the ‘missing’ storms.
 
They find that if arctic hurricanes decrease over the next 20 to 50 years as predicted, we could expect to see an accompanying weakening of the thermohaline circulation that might be able to offset some of the warming predicted for Europe and North America.