Cold air flowing over a warmer sea gives rise to Maine’s rarest — and most beautiful — type of fog.
By Kim Ridley[I]’ve been attempting the quixotic art of loving winter in Maine ever since I moved back to my home state, 20 years ago. One year, I learned to identify the sea ducks that spend winter on the bays around my home in Brooklin. The next year, I took a class in winter botany to better appreciate six months of leafless trees. My husband Tom and I have organized winter bonfires and skied around the neighborhood under a full moon. We’ve gawped at winter stars from an outdoor wood-fired hot tub he built with a friend. One night, it was so cold that the steam froze in our hair.
On a clear Sunday morning last February, however, I realized I still had a long way to go in learning to love winter. After epic snows and days of pipe-bursting cold, I found myself binge-browsing vacation villas in the Caribbean.
It took the crows hollering outside to get me out of my chair and looking out the window. I never saw what set them off, but I noticed odd tufts of pink fog cartwheeling low over the horizon. It was coming from the harbor, a quarter-mile away. Tom and I scrambled into our puffy ski pants, grabbed cameras, and sped down to the boatyard. The dashboard thermometer read 5 degrees.
The harbor steamed like a pot of soup. Spires and drifts of mist whirled across the silver foil of the sea, and the sky was a clear, hard blue. The vapor had turned from pink to gold in the rising sun, and we watched, mesmerized, until it faded to white. The mist obliterated the bottom half of a small island just offshore, making it appear to hover in mid-air. The next minute, the veil lifted and the entire island emerged. We watched, spellbound, until the cold drove us back into the car.
I’d seen this phenomenon only a few times, and always on the coldest days: sea smoke, Maine’s rarest kind of fog.
Sea smoke is friskier and more fleeting than other kinds of fog, like the common radiation fog that blankets lowlands at sunrise, a symptom of cool overnight temps that cause water vapor in the lower atmosphere to condense.
And unlike the dense walls of sea fog that have sent me paddling my kayak hard for shore in summer, sea smoke tends to be more transparent and wispy. It hugs the water’s surface and sends up spinning columns of vapor.
Back home, I called National Weather Service meteorologist John Cannon in Gray. He told me that sea smoke (also known as arctic sea smoke) forms when very cold air flows over relatively warmer seawater. As the water evaporates, the cold air above it can hold only so much moisture before it condenses into fog. The water steams just like a cup of tea — indeed, when this occurs over a river or lake, it’s called steam fog.
Sea smoke can start forming as early as November, when the air temperature over the ocean is in the low 20s and the seawater temperature is still in the 50s. Maine’s bays and coves really get smoking when air temperatures along the coast plummet to 10 degrees or lower. The colder and more still the air, the more likely the sea smoke will be spectacular. Winds of 20 knots or higher will whisk away evaporating moisture before sea smoke has a chance to form.
“The last few winters have been cold and severe enough that we’ve started to see more sea smoke,” Cannon told me. “Last year was exceptionally cold, and there was arctic sea smoke very late into the season, which is a true rarity.”
Low rolling as it is, sea smoke rarely causes problems for ships and other large vessels, but it can be a hazard for smaller craft like lobsterboats. To give operators a heads-up, the National Weather Service measures visibility over Maine’s coastal waters with special buoys fitted with sensors and located a few miles offshore.
We’ve come around to winter again, and droves of neighbors have migrated south. On frigid mornings when I wish I could flee winter myself, I’ll bundle up and head to the shore. Watching the harbor steam pink and gold and white, I’ll think about those who ply the water in small boats in all seasons. I’ll listen to the yodeling calls of long-tailed ducks, and for as long as I can stand the cold, savor the frosty morning. It won’t be long before the sea smoke is gone and the wind swings around to the southwest, sweeping the sea ducks north and bringing the songbirds back.
Top photo: Owls Head Harbor — by Benjamin Williamson