Typhoon Haiyan
Unfortunately, cyclonic storms like typhoons are among the world’s deadliest natural disasters, right up there with tsunami, large volcanoes, and major earthquakes. Nothing mankind can presently alter let alone stop any of these thousand kilometer wide events.
Hurricane Harvey
The planet’s weather is driven by the Sun and some heat radiating out from the Earth’s core. It heats the oceans surface water which release water vapor making storm clouds and packing heat energy into the atmosphere. Meanwhile, the Earth turns. We are on a big spinning ball which is zipping along quite quickly, rotating at 1,670 kph at the equator. So that imparts a lot of physical rotational energy to this gigantic moving mass of humid air, some quite warm some frigid cold.. So there are also these big temperature variations… On top of that, hot air rises while cold air settles.
In the US, that means cold dry air pours down out of the Rocky Mountains across the Great Plains right where hot wet air is flowing north up the Mississippi River valley. Toss in some of that rotational energy and some magic called “shear winds” and you end up with a horizontal rotating cylinder of warm and cold air. Shear winds can push the cylinder downwards, spinning faster, drawing in towards the center spinning faster and faster, and Boom! It’s a tornado.
Typhoons, cyclones and hurricanes are sea beasts, fed by hot and hotter ocean temperatures as the global climate heats up. All across the tropics Very warm Very wet air loads immense energy into the air. Here the rotating Earth causes gigantic eddies in the air caused by the coriolis effect- a physical thing that happens to rotating spheres that causes rotating weather patterns…
All this spinning and ocean heat energy going up into the spinning air is a potent mix. The storms are generally seasonal- or used to me most of my life- I left out two other big factors in Pacific and Indian Ocean basin storms: El Nino/nina, and the Indian Ocean version. These are semi seasonal movements of warm surface water heading one way while cold deep water dozens of kilometers deep flows the opposite way. (there is another one of those big temperature differences!)
A column of warm wet air rises up forming a low pressure zone, sucking in cooler surrounding air, which then shoots up. The rotating Earth meanwhile is imparting a spin- counterclockwise in the north, clockwise in the south. Along comes shear winds up high and the storm gets the green light to grow. These days, they can grow really fast. We see storm meandering along at a Cat 1 level, and almost overnight they are Cat 3 or higher. Then they stall out, dumping trillions of liters of rain in a few days.
All people can do is be prepared with emergency evacuation plans, hardened shelters and supplies. And climate change is making the worst storms more frequent.
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