The whys of windy weather
I love to hear people ask questions; it’s the only way to learn.
Pam and Mike Gaul made a very accurate observation that lead to a great question: “My husband and I are bikers and boaters and therefore very wind-conscious. In conversations with others, we all anecdotally are commenting on how much windier our weather has become in the last few years. Are we crazy or is there historical wind data to confirm our thoughts?”
Wind is tricky, especially at the coast. Wind direction, wind speed, and the frequency and strength of wind gusts can vary over a relatively short distance.
Wind is defined as a natural movement of air: In nature, air flows from an area of high pressure to an area of low pressure. Wind speeds are determined by the rate of change in pressure between atmospheric areas.
Now let’s step back and talk about climate change for a moment.
Most scientists agree that one of the biggest differences we’ll see over our lifetime is the intensity of storms; we can expect more weather extremes. There may not be more rain or more snow, but systems will become more powerful, with an increase in the amount of heat and available moisture in the atmosphere as temperature continue to rise. The more powerful the storm, the lower the air pressure. The difference in air pressure between the storm and the adjacent air masses becomes more significant and the flow from the relative high pressure surrounding the storm is amplified. That creates wind.
So yes, it has been getting windier and that trend will most likely continue.
I’d also like to touch on this past winter here in the Maritimes. Many people have noticed and are commenting on how windy it was.
It was a very windy winter and we can blame our friends in Ontario and Quebec. They didn’t have much wind at all, but it was bitterly cold. Their winter started in November and didn’t loosen its grip until April. Here at the coast we didn’t have much winter at all. The air mass that was anchored west of us was very cold; the air masses that travelled up along the seaboard all winter were relatively warm. Cold air is dense air and dense air has a higher air pressure. In nature everything seeks equilibrium, so the cold, dense air rushes out towards the nearest area of lower pressure. All winter, “we” were that area of lower pressure.
That’s an overview of the wind scenario. It doesn’t explain the odd windy day or a windless weekend but I hope it answers Pam and Mike’s question.
If you have a weather question for me please send it along to Weathermail@ weatherbyday.ca I’ll do my best to answer it.