An unusual sighting on the Lake Ontario shoreline in Oswego last week

If you were in Oswego on the shores of Lake Ontario last Wednesday you probably saw something that you don’t see everyday. What’s that? The north shore of Lake Ontario, or the Canadian shoreline!

Typically, when you look over Lake Ontario from Oswego or anywhere along the south shore of Lake Ontario you do not see any land mass when looking north, but every so often the Canadian shoreline will appear for a short while!

What causes the Canadian shoreline to appear every so often? It’s a process called looming. Here’s how it works.

First, I’ll use an example which is the bending of light in the opposite direction compared to looming. Do you recall on a hot/warm summer day looking at the blacktop in your driveway or the road? When you are looking at the blacktop you typically can see a distorted image of what looks to be a puddle reflecting an image of what’s ahead seemingly floating just above the road. Why’s that?

It’s because the light waves that are coming back to your eyes are bending due to the different speeds at which the light is traveling to your eyes. Light travels faster in warmer, less dense, air than it does in colder, denser, air. So since the light from the hotter road/driveway surface gets to you faster than the light traveling in the cooler air above the hotter air it causes what you are seeing just above the blacktop to be distorted/warped. Also known as the puddle effect because the distorted image looks like a puddle of water. This process is called sinking which is the opposite of looming.

Okay, now remember the sinking process causes that image of the puddle of water on the hot blacktop that really isn’t there.

The looming phenomena occurs over Lake Ontario mostly during the spring season due to the temperature profile over the lake. The type of day most supportive for looming is a sunny, warmer day with low humidity. There needs to be a significant enough difference between the air temperature several feet above the Lake Ontario surface and cooler the air just above the chillier Lake Ontario surface.

What happens is that the light waves coming to your eyes are being bent like the top of a semicircle because the light traveling through the colder, denser air just above the Lake Ontario surface will be reaching your eyes not as quickly as the light waves several feet above where the air is warmer. This difference in speed in which the light enters your eyes creates the bending of light/refraction resulting in a view of the north/Canadian shoreline seemingly above or on the horizon. It’s like a big mirror is placed at an angle above the Canadian shoreline so we can see it.

Below is a great video and some pictures from Daniel Maslowski showcasing looming taking place last Wednesday, April 7th.

So next time you are up on the Lake Ontario shoreline maybe stopping for lunch at Rudy’s or having a picnic on the shore this sometime this spring maybe you’ll be fortunate enough to have a view of Canada!