My friend the geophysicist emailed the other day to tell me his house in Connecticut was still snowed in. "The main hypotheses for why we have so much snow," he explained, "involve heat coming out of the now-open Arctic ocean in early winter. Once the ice cap freezes over temporarily, the wild weather calms down."
In other words, it's caused by global warming. Not global warming next year. Not global warming 50 years from now. Global warming today. And according to a new study published in Nature, the entire continent of North America is affected:
"Human influence on the climate system has the effect of intensifying precipitation extremes," said Francis Zwiers, a climate researcher at Environment Canada in Toronto and lead researcher on the first study....The study found that observed increase in deluges "cannot be explained by natural internal fluctuations of the climate system alone," said Zwiers. In other words, only the addition of greenhouse gases to the atmosphere explains why the United States and Canada have experienced a dramatic increase in heavy downpours.
....The explanation is simple physics: Warmer air holds more water vapor. That means when rainfall gets triggered, the air contributing to the storm is holding more water than it did in the cooler pre-industrial world.
And it's not just North America. Another new study looked at the epic floods in England and Wales in 2000 and concluded that they likely resulted from a warmer world:
In nine out of ten cases our model results indicate that twentieth-century anthropogenic greenhouse gas emissions increased the risk of floods occurring in England and Wales in autumn 2000 by more than 20%, and in two out of three cases by more than 90%.
And the even scarier part? These studies only go through the year 2000, so they miss the entire last decade, which was the warmest on record. And needless to say, England and North America are far from being the areas worst affected by climate change. What we're seeing here is just a small taste of what's to come in the future and in other parts of the globe. Buckle up.
Front page illustration by Celine Nadeau.