Sulfur dioxide is one of the by-products of volcanic eruptions…all eruptions send it into the atmosphere. Small eruptions release a little, big eruptions a lot. Sulfur dioxide acts like a “radiation mirror”, reflecting the sun’s energy back into space. Really big volcanic eruptions can cause enough solar power to be reflected to actually cool the earth and alter weather patterns. Mt. Krakatoa’s eruption in August of 1883 did just that, and it affected the weather for several years.
And as we already know, weather is unstable enough. David Laskin writes, “Constantly and futilely, the earth’s atmosphere seeks to achieve equilibrium. Weather is the turbulent means to this perfect, hopeless end. Contrasting temperatures try to balance out to one uniform temperature, pressure differences strive for resolution, winds blow in a vain attempt to finally calm down global tensions. All of this is enormously complicated by the ceaseless rotation of the planet. Weather is the steam the atmosphere lets off as it heaves itself again and again into a more comfortable position. Weather keeps happening because the equilibrium of the atmosphere keeps getting messed up.”
As Christmas of 1887 gave way to the New Year, a large pocket of super-cooled air formed over Alberta, Canada, caused by a combination of factors. Winters in northern Canada feature only a couple hours of sunlight, and much of that can’t be absorbed by the snow-covered surface. Add in high pressure, very light winds, and the possibility that Krakatoa’s residue was still in play, and the region that saw average temperatures of -15°F was now an even more frigid -35°F.
At first, it’s hard to see how this is really news-worthy. After all, it’s Canada, it’s winter, it’s cold. You kind of expect it…our weather south of the border hasn’t been, for the last 2 weeks, all that much warmer. But things changed on January 10, 1888.
It was then that the jet stream dove down from the Yukon and ran into the Canadian Rockies. The currents slid down the mountains, warming as they did, and collided with the super cold air mass that had stagnated there. The drop in air pressure created a powerful low that, propelled by high pressure behind it, began sliding to the south.
In the meantime, many hundreds of miles to the south, a wave of warm, moist air was surging northward from Oklahoma, which would dramatically warm the upper Midwest, and provide welcome relief from the unseasonably cold weather.
Both air masses, the cold from the north and the warm from the south, were impressively powerful on their own. But when the warm air collided with the cold, it would create a storm of awesome power. Stay tuned…
Recommended Reading: The Children’s Blizzard – A “glue” book. Once it’s in your hands, it gets stuck until the last page is finished.
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