How less sea ice is impacting weather, coastlines

We’re at the peak of another sea ice season in Atlantic Canada.

While we obviously don’t have full data for the season yet, sea ice amounts for the East Coast will likely finish below average due to factors such as delayed growth and formation early in the season and temperature fluctuations.

If you’re noticing a delayed start or less sea ice during the winter season, you’re not alone.

“There’s definitely been a decreasing trend for sea ice in Atlantic Canada,” said Jason Ross, senior ice forecaster with the Canadian Ice Service at Environment and Climate Change Canada. “It forms later in the year and because of that it doesn’t grow as thick and also doesn’t grow to the extent that it would had it formed earlier in the year.”

Several factors ranging from air and ocean temperatures to the intensity of winter storms can determine the amount of sea ice in the winter.

Ross added while the trend is not linear, and not every year is a low year, there have been more and more years with less sea ice.

Less sea ice during the winter can affect our weather in many ways. Sea ice reflects the sunlight, allowing surrounding temperatures to be cooler while open waters absorb the sunlight and can warm the area.

A delay in sea ice formation, or less ice overall, can also lead to more sea-effect snow. While many areas are experiencing less snow due to climate change, it’s possible those prone to sea-effect snow could see an increase in the average amount of snowfall.

Sea ice is also integral to protecting some coastlines from wave action during harsh winter storms. And less sea ice is certainly showing its impact.

“This year we noticed that near-shore ice did not form by the time that it historically had formed,” said Garrett Mombourquette, acting resource conservation manager with Parks Canada. “As a result, we were particularly exposed to several winter storm events that occurred resulting in erosion of between one and two metres across the park, varying extents in different parts of the park of course.”

To put that into context, parts of the park have already experienced the amount of erosion typically seen over the course of a total year.

Less winter sea ice is just another way our climate is changing in Atlantic Canada.

You can watch my full Behind the Weather video feature on sea ice at saltwire. com/weather under “Featured Ask Allister”.