I felt a little guilty driving into work today with the air conditioning on in the car, with the thought that I’m living through the last days of a planet. But weather is not climate… except when it is, I found out this afternoon.
Today, the Bad Astronomy blog asks, “when does weather become climate?” And then answers, “now.”
Is all this due to global warming? Hard to say, exactly. However, these conditions are precisely what you would expect as the Earth warms: weather patterns change, temperature records get broken, conditions go from normally wet to dry, normally dry to wet.
“Weather” is what you look at if you want to know if you need an umbrella or not today. “Climate” is what you expect on average for a given day in a given place. Weather changes on short time scales; climate over long ones. But how long?
Weather + time = climate. It’s well past time to start thinking of that “time” as now.
NASA, too, jumps into the “it’s climate!” declaration in explaining the latest land temperature analysis in the United States, which shows it’s overwhelmingly hot.
This heat wave, like all extreme weather events, has its direct cause in a complex set of atmospheric conditions that produce short-term weather. However, weather occurs within the broader context of the climate, and there’s a high level of agreement among scientists that global warming has made it more likely that heat waves of this magnitude will occur.