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Earthquakes, floods and volcanoes: The most disaster-prone places in America

Fires. Floods. Storms. Hurricanes. Volcanoes! The Federal Emergency Management Agency has declared more than 3,000 disasters since 1953, covering the gamut of large-scale calamities ranging from tornadoes to terrorism, and everything in between. Since 1964, they've been tracking these disaster declarations at the county level, which I've mapped below. Click on any county to get a detailed breakdown of each category of disaster for that county.

First things first: what is a "disaster"? As you might suspect, there are specific rules about when and how a disaster gets declared. For our purposes, it's important that a state governor must first request a federal disaster declaration applying to one or more counties, and then the president must approve it following review. So in some ways a disaster declaration is just as much a political phenomenon as a natural one.

The politics of disaster declaration may be somewhat reflected in the map above, as you'll notice that some states are more disaster-prone than their neighbors. Wyoming and Georgia stand out as states where disaster declarations are relatively rare -- does this mean that the weather is simply milder here, or that for various political and cultural reasons governors in these states are less likely to request disaster aid than their peers in neighboring states?

Qualitatively, disasters encompass a range of natural and some man-made phenomena. Severe storms rack up the most disaster declarations, 853 since 1953. Fires and floods aren't far behind. Hurricanes, tornadoes and snowstorms make up a second tier of disasters by frequency. Beyond these are a hodge-podge of categories that haven't broken the 100 mark.

The lesser categories include typhoons and coastal storms that mostly impact our territories in the Pacific. There have been six disasters declared due to fishing losses, from toxic algae blooms and the 1994 el nino that affected the Pacific salmon industry. There have also been seven toxic substance spills, three dam breaks and 27 disasters classified simply as "other." These include severe hardship in Alaska in the 1950s, a grain elevator explosion in Kansas in 1998, and President Obama's first inauguration in 2009, which George W. Bush declared a state of emergencyto free up funds for.

It's important to remember that one disaster declaration can impact multiple counties. For a sense of which disasters affect which regions of the country, I've mapped eight of the largest disaster categories below. Click the image for a closer look.

Severe storms are the most widespread disaster, although they're clustered heavily in the middle of the country. Interestingly, Illinois stands out as an oasis among it's storm-prone neighbors -- this may be due to Illinois governors' relative reluctance to request disaster aid for storms.

North Dakota counties seem to be the most impacted by flooding -- the Red River is a big culprit here. You can also see a ribbon of higher concentration in the counties along the Mississippi river.

The Gulf Coast is lit up in the hurricane map, as are Florida and North Carolina. Interestingly, Georgia and South Carolina are spared from much of it. You'll notice several inland states indicating a single disaster declaration here -- when's the last time Nebraska was threatened by a hurricane? In fact, most of these inland declarations are due to evacuations caused by Hurricane Katrina -- disaster declarations in these states allowed local authorities to request federal funds to help deal with the influx of evacuees.

I also want to point out the map of freeze disaster declarations, which are heavily concentrated in Florida and California -- major agricultural areas. It illustrates how a disaster's impact depends heavily on local conditions -- January temperatures in the 30s and 40s wouldn't cause anyone to bat an eye in, say, Minnesota, but move that same weather down to Florida and you've got a calamity for the citrus industry. It also makes you wonder how hellaciously cold it would have to be to declare a disaster due to cold in Northern Maine.

Now that we've got a sense of the disaster landscape, we can return to the big map, which I put just above so you don't have to scroll all the way back to the top. This map lets us see which counties have suffered through the most disasters since 1964. The award for most disaster-prone place in the U.S. goes to Los Angeles County, CA, which has experienced 53 disasters in that time period -- on average, a little more than one disaster per year. These include 35 fires, 6 each of storms and floods, 1 hurricane-related (Katrina evacuees), 3 earthquakes, and 2 deep freezes.

In fact, Southern California counties account for four of the top 5 disaster-prone counties in the U.S., driven primarily by the frequency of fires and floods there. Oklahoma County, OK comes in at number 4, on the strength of its severe storms, fires and ice storms. 

Collier County, on Florida's Gulf Coast, comes in at number seven with its 15 hurricane disasters, 7 fires, 5 severe storms, 5 freezes, and a tornado for good measure. But Collier doesn't lead on hurricanes -- that honor goes to Terrebonne and Plaquemines parishes in Louisiana, tied at 18 hurricane disasters each. Of the top ten counties for hurricane declarations, eight are in Louisiana.

As I mentioned above, the top flood counties are clustered in North Dakota and Western Minnesota along the border of the Red River. 22 of the top 25 counties for flood declarations are in this region. If snow is your thing, you'll want to head to Western New York, where Erie County has been on the receiving end of 10 heavy snow disasters since 1964.

But the map also shows where disasters aren't being declared. Wyoming hardly has any, although they'll get theirs if the Yellowstone supervolcanoblows its top. Northern Michigan is also relatively disaster-free, as are parts of Idaho, Utah and Nevada.

So: there you have it. Do you want to live on the edge? Head to Southern California. Or Oklahoma. Prefer to play it safe? Maybe Wyoming is more your speed. And avoid presidential inaugurations when you can.