What is a Thunderstorm?

I realize I am a bit late to this story, but want to comment anyway. Last month the internet in China (and globally) was buzzing with word of a mysterious mushroom cloud that had appeared in the skies over Beijing late one afternoon.  Photos were posted on blogs and micro-blogs, and it didn’t take long for speculation and rumors to begin swirling as the cause of the cloud.  Had there been a chemical leak? Had North Korea blown itself up?

Of course, it was just a thunderstorm.  But why would a giant thunder cloud on the horizon be greeted with such shock and confusion?  After all, it is summer in Beijing, and thunderstorms are almost daily occurrences.

I have a theory as to why this one caused such consternation. Most of the time, the sky in Beijing is white, thanks to the pollution. Actual clouds are not visible, so people here rarely have the chance to see giant thunderhead clouds billowing up to the heavens.  In other words, the thunderstorms are virtually invisible.  The white sky becomes a bit darker, then BOOM!!  That’s the only way we know a thunderstorm is upon us..

Here in Minnesota we also get summer thunderstorms, but here we can see them marching  towards us from the horizon. Sometimes, in the late afternoon, we may be sitting in the sunshine, but can look around and see a thunderhead 30 miles north, or 10 miles south, or 5 miles east, or 50 miles west. They are gorgeous, and they look like mushroom clouds.  In fact, I spotted a cloud similar to this as I was driving home from my sister’s house this evening.

Last month’s storm rolled through on an unusually clear day in Beijing, so the thunderhead was clearly visible.  And that freaked people out.

(Image source: People’s Daily)