Sunday, August 30, 2015

Why does the U.S. have more tornadoes than any other country?


FEMA image in the public domain


In brief, the answer to this is a three-parter:

1) Geology + temperature.
2) It doesn't. England has more per square kilometer.
3) Some details are still unknown, and that might change the answer

What is widely accepted:
  • Low elevation moisture comes from the Gulf, sweeping across Texas and into Tornado Alley (the red parts of the map, above).
  • High, hot dry air from the SW desert creates a high cap.
  • Cold air swoops down from the Rocky Mountains. It's crucial that the mountains run North-South for storm formation. A country split by east-west mountains would not have this ingredient.
  • All of this gets stirred together, and a new front can send that moist air up and up. Clouds form. Add circulation, and you get supercell thunderstorms.


Supercell, by NOAA, seen from the south

You'll notice I slid right past that "add circulation" bit. Here is where scientists are still trying to untangle the knot that is tornadogenesis and tease out those facts. Why will some storms rotate quickly and others hardly at all? Bit by bit, the scientists are closing in on an answer, but they aren't quite there yet.

30-50 degrees latitude is currently the sweet spot for tornadoes. If the weather continues to steadily heat up worldwide, that will shift northward, and Canada may one day rival the US for tornadoes.

If the US were three countries--west of the Rockies, middle third, and east-coast states--the two coastal thirds would have a more typical number of tornadoes. It's that middle third that gets slammed with the EF4 and EF5 tornadoes that turns the US into tornado central. England may have more tornadoes for its area, but they tend to be EF1 storms.

If you meet people from Oklahoma, which has the majority of the worst tornadoes, ask them about twisters and you'll discover this: most have never seen a tornado in person. Like the rest of us, they mostly see video of them on TV, over in the next county. I've seen one in Illinois, IRL, from a distance, which I think we can all agree is the ideal way to see one.

I have a tornado novel written, by the way, with major revisions done, but I need to get the last Gray novel out before I return to it and finish the final edits of it. It'll be out in early 2016, I think.

Sunday, August 23, 2015

Natural Disaster History: Krakatoa, 1883

August is the anniversary of the most famous of volcanic eruptions, the Krakatoa eruption in Indonesia. In the last week of August, 132 years ago, the volcano entered its final phase of eruption, an event that had been building for six months. With a force much more powerful than any nuclear weapon ever detonated, its final eruption sent an ash plume 50 miles into the air and burst the eardrums of people 40 miles away. It was heard clearly in Australia, Manilla, and in islands just west of Madagascar, and the shock wave was recorded on barographs as it swept around the world seven times.

Over 36,000 people died. Pyroclastic flow killed islanders nearby, and a hot rain of ash and stone killed more people 30 miles off. The following tsunami resulted in most of the deaths, and some argue that it caused well over 50,000 deaths not included in the 36,000 figure.

For months afterwards, there were spectacular sunsets from the particulates in the air, as well as changes to weather that lasted five years.

If you had been hanging out on the planet Mars at the time, you would have seen the Earth get--and remain for years--considerably brighter as the particulates increased the albedo of the planet's atmosphere.

Westerners living in the area or sailing nearby took notes that reached newspapers on the other side of the globe quickly. It was the first natural disaster that was reported so quickly, and widely. We take this for granted today, but the technologies for communication were new then.

While not the biggest volcanic eruption in the past 1000 years, it happened when communication and science technologies had progressed to such a point that its importance to the science of volcanology could hardly be overstated. It also revealed to meteorologists new information about high-level winds.

In 2003, Simon Winchester wrote a terrific non-fiction book about it, well worth reading if you're as into natural disasters as I am. Also, you could mosey on over to youtube and look for uploaded TV specials on the topic, like this one: https://www.youtube.com/watch?v=MrEIT66oPqU

Sunday, August 16, 2015

Half of Americans at risk of earthquakes

A new study in Earthquake Spectra that reminds us of the truth of the seismic hazards map in the US is getting a lot of press coverage, and that's a good thing, in my opinion. Here's one link, and there's another good article at National Geographic.

USGS

Wednesday, August 12, 2015

Things are a-changing around here...

I'm very excited about my current project: revamping of my books. I'm finishing up on pro copyediting this month, getting all new covers next month, upgrading the interior designs, and I will have paperback versions up before the end of the year.

I thank my terrific readers for enjoying my books; without your buying the books, I could never have afforded to do this. So I'm pouring the income back into the business and will give you a better product as a result.

Remember, keep your "automatic updates" on for kindle books, and when authors do this sort of thing, you'll be able to have the best version of the books in your collection.

(And, for fans of the Gray series, I'm still working on Gray III. There's a horrifying opening scene....)

Sunday, August 9, 2015

Prepared vs. Prepper

When I talk to people these days about the importance of being prepared for a disaster, they sometimes edge away and say "I'm not one of those extremist prepper people!"

You don't have to be. Personally, I think if there's an entire collapse of civilization, I'm doomed anyway, and I'm not sure I'd want to be the last one standing after a nuclear holocaust or asteroid hit. Furthermore, the likelihood of those is remote, so I don't worry about them. (If you do worry, and go the whole prepper route, and can afford to spend the time and money on it, good on you.)

What I would like you to think about, though, are the disasters that actually do kill people and are likely in your area. You needn't prepare for The End of The World. But do prepare to avoid the possible end of your world.
Red Cross Emergency Kit. Image FEMA

Number one on your list of preparations to make should be not for a natural disaster but the common house fire. 2,650 deaths per year in the US are due to these, and you'll see proportional numbers in other countries. Make sure your smoke detectors are working, check the expiration date on any fire extinguishers you own, and run a fire drill for your family once a year. Choose an annual date: your birthday is good, or use ShakeOut Day (October 15), a good day to think about disasters beyond earthquakes, too. Have your plan in place, and practice. The more that people practice what to do in such a situation, the more likely they will survive.

If you take care of no other preparations, please, take care of that.

Anyone can lose electricity due to weather extremes or brown-out. I'd rank this area of preparation next, particularly if you live somewhere it gets well below freezing or above 90F/30C. If you have insulin in the refrigerator, you need to think through what you'll do with it if the power is out for a week. If your continued existence depends on a breathing device that runs off electricity, you need a plan for producing electricity. While it's true that homo sapiens existed for hundreds of thousands of years without electricity, and most of us could probably survive a week without if we had some canned food and crackers, being prepared for the loss of power is a good idea.

Still with me and have more energy for preparing? Next on your list should be preparing for the one most common natural disaster in your area. If you live in northern Minnesota or most of Canada, that's going to be cold weather and blizzards, and I bet if you do live there, you're prepared for it, with extra clothes in your car, road flares, chains, and possibly a generator at home. If you live in Oklahoma or northern Texas or Kansas, you're going to know what to do in the case of a tornado. Coastal Californians think often about earthquakes. (And people in Memphis and St. Louis and Seattle need to think about them more--they're rare but can be terrible there when they do arrive.) The Gulf Coast is prepared for hurricanes. Hawai'ians know the tsunami evacuation routes. My readers in Australia know a good deal about wildfires.

I happen to live in a place with almost no chance of any natural disaster, but there are nuclear plants upwind, so I'm prepared for that sort of disaster. I have a bug-out kit in my car trunk, and I never let the petrol get below a half a tank in my car. In most disasters, sheltering in place is the smartest option, but with hurricanes/typhoons and nuclear plant disasters, evacuating is the preferred response. Preparing for it took me a few hours of buying and packing supplies over a week's time, but it only takes me a few minutes a year to make sure they're all still in place. I could be on the road in less than five minutes.

To summarize, please prepare for these: 1) Home fire. 2) Loss of electricity. 3) The number 1 likely natural disaster for your region. It's not extremist to do so--it's smart.

Sunday, August 2, 2015

If there were a repeat of the 1811 New Madrid Earthquake

USGS, from a previous study


A new paper in the Bulletin of the Seismological Society of America addresses what would happen today if there were a repeat of the historical New Madrid quakes (as occurs in my novel, Quake.) "More than eight million people living and working near the NMSZ would experience potentially damaging ground motion and modified Mercalli intensities ranging from VI to VIII if a repeat of the 1811–1812 earthquakes occurred today. Moreover, the duration of strong ground shaking in the greater Memphis metropolitan area could last from 30 to more than 60 s, depending on the magnitude and epicenter."

If you don't have access to scientific journals, a short article summarizing the paper is here