Fascination with tornadoes

This last Sunday, a string of deadly tornadoes wreaked havoc in the USA. 29 deaths have been accounted for, numerous towns have been destroyed, and people are still making sense of what happened. Meanwhile, the news channels are showing the same wreckage again and again.

But if we seperate the risk from the phenomenon, tornadoes take on a whole different allure. When you watch tornado videos on Youtube, you can't help but feel oddly fascinated by them. I mean, it's like God extended a finger down from heaven and swirled it around, like one would swirl a tequila.

South Dakota tornado, by Carsten Peter for National Geographic.

Most everyone falls into two categories: either you're morbidly fascinated by tornadoes, or you're panicked by them. You can't really ignore it. Such extreme power demands attention.

To understand tornadoes, meterologists dedicate their lives to studying their formation. Some go out on the field to film the supercells that are responsible for making tornadoes. But it's obviously a high-risk job. Last May, a famous Storm-chaser, Tim Samara, was killed doing what he loved best.

Here's what happens: Springtime in the USA means that cold air from Canada meets warmer air coming in from Mexico. Since the two masses of air come from different directions and at different speeds, this creates a vortex between the lower layer of air and the higher air. The vortex is horizontal; however, it can be tilted upwards until it forms a funnel cloud, which you probably recognize as the tail of a tornado. To understand more, watch the video below by Science America.

But why do the US have so many tornadoes? They have over 1000 tornadoes per year, making them the planet's favorite tornado place, being that the second is Canada (more than 100 tornadoes per year). Well, it's because of the convergence of air from the Gulf of Mexico and Canada and the enormous difference of temperature between them. The temperature shock creates greater winds, which in turn create thunderstorm supercells, nearly essential for tornadoes. Furthermore, the two American mountain ranges (the Appalachians and the Rockies) channel the convergence of the two air masses over the giant plains that stretch across the Midwest. This combination is so dangerous that part of this area is called the Tornado Alley.

Tornado alley by NOAA.

But tornadoes can be seen in nearly all parts of the world, such as demonstrated by the video below of a waterspout in Florianopolis, Brazil, in 2008.

Sometimes I wonder if the reason that we're truly fascinated by tornadoes isn't because they're great and powerful- it's because they have the power to kill us, and because we're naturally fascinated with everything that can kill us. Just like Formula One- nobody really watches it for the race itself.  You watch it because people race each other in combustible machines that reach 270 km/h. It's the brush with death that captivates us.

But that's another story.

Keep tuned for more on Tracking Stories.

It's not nature's fault

Here I was, studying Management of Natural Risks, when my family alerts me of a very real disaster going on not to far from where they live.

Blumenau on a sunny day, bordered by Rio Itajai. Photo from Wikicommons

My mother's family is from a cute little town called Blumenau, which means Field of Flowers in German, and is one of the German towns set up by pioneers in the late 19th century in Southern Brazil. You see, these German pioneers were practical. They knew that living near a water source would help them with their early development and getting started in a new country. So they picked a site next to a large river bend, built sturdy German houses, and named the town after flowers. It couldn't get much better than that.

But Brazilian climate tends to be a little more unpredictable. Southern Brazil is predominately Atlantic rainforest- or at least it is supposed to be. There is a large annual rainfall, electrical storms, and even some tornados off east. Once the riparian forest was gone, the river started swelling and causing enormous, catastrophic floods. The first recorded flood was September 23rd, 1880. The worst ones were in 1983 and 1984. My mom was a teen at that time. She remembers the streets becoming rivers and drinking water from the neighbor's swimming pool, because it was the only potable water left. 

Unfortunately, it wasn't the last. The last one was in 2008. It killed over a hundred people and moved thousands out of their homes. Many still don't have where to live. I've seen stories on tv of people that have no idea what to do next. They shake their fists into the air, wondering why this happened to them.

While it might not be their fault that they lived in such a precarious position, it certainly isn't nature's fault. This is Brazil. This is a climate that is used to very rainy seasons that may pop up once a century or twenty times. It's unpredictable. You cannot, and must not, do anything to change that.

What you can do is to reduce its consequences. It's the first thing I learned on my very first day of class this year : Risks are there. You can't change them. Earthquakes will happen, volcanoes will spew lava, rain might fall for 40 days and cause a flood. Earth is like that. We have to learn to live with it instead of fighting it. Luckily, most of these events are predictable. The Japonese have learned to deal with earthquakes by building seismic-proof buildings. The Dutch have built dikes to keep their country from disappearing bit by bit. 

Unfortunately for those who live in Blumenau, it's very hard to deal with this particular risk. Those who live on low lands often don't have the choice of moving elsewhere. The high lands are too far from the city and there's not enough money to move away. Sometimes the solution is asking for the government to step in and offer solutions : maybe subsidizing building companies to construct other buildings on the highlands, and connecting it with a good transport system so they won't be cut off from the city. Maybe it's making a system so that those who do construct on forbidden land are penalized. What I do know is that it's necessary to create a fool-proof risk system so that accidents like these don't happen again.

Because it will rain again. And again, and again. The trees love it, and so does the entire ecosystem. What can I say? It's a little piece of paradise down there. I just hope that people will protect it and not get mad at it.

These two guys were chilling out near São Martinho, Brazil. Lime green toucans are common in the Atlantic Rainforest.