Have there been more natural disasters than usual in recent years? Or are there just more videos of them on YouTube? —Haley Block
For once, our answer is a pretty clear yes. According to the World Meteorological Organization, humanity experienced nearly five times as many natural disasters (3,496) in the first decade of this century as we did during the 1980s (743). That said, the increase in the sheer number of events isn't as simple as it seems. For one thing, as you've pointed out, everything's better-documented these days—though how anyone manages to appropriately angle their phone to film themselves running down Everest away from an avalanche and then moments later post it online is beyond my imagination. I care about you, dear readers, but if the earth opens up to swallow me as I sit at my desk writing this, your viewing pleasure won't be my immediate concern.
Backing up a bit: As a species and a planet we're more vulnerable to cataclysmic events than in the past, and a considerable part of this vulnerability comes from climate change. It's of course impossible to pinpoint what percentage of events are directly our fault, but there are signs we're not doing ourselves any favors. If you divide disasters into climate-related events (tornadoes and hurricanes, flooding, etc.) and geophysical occurrences (earthquakes, tsunamis), the latter have remained basically steady for decades while the former are responsible for at least 80 percent of the overall increase in reported disasters. Floods and megastorms represented 89 percent of all disasters between 1970 and 2012. Heat waves are responsible for a much larger proportion of deaths in the last decade than ever before, and some of the deadliest killers of the past half-century were droughts in East Africa.
And over that same 42-year period, damage from storms, droughts, and flooding (in that order) have cost the most money—more than 80 percent of overall disaster losses worldwide. But 10 percent of that went just to the Sandy and Katrina cleanups (and in Katrina's case, the cleanup of the cleanup). Which stands to reason: it obviously costs a lot more to repair disaster damage in New York City than in Sri Lanka, and the money is more easily come by.
You see where it gets tricky—the definition of natural disaster is unavoidably tied to the number of people affected and/or the value of the damage done, both of which will naturally increase as the Earth's population and wealth do, and of course wealth and population aren't evenly distributed worldwide. And that brings us to the other big part of our growing vulnerability to disasters: urban migration in developing countries means denser populations, which often goes hand in hand with quickly-assembled, not overly sturdy housing. The parts of the world where this is most common tend to have largely informal economies, in which the enforcement of building-code regulations may not be a top priority. All this makes it much more likely that a serious meteorological or seismic event will meet the Office of U.S. Foreign Disaster Assistance's criteria for a disaster: ten or more people killed and at least 100 injured, evacuated, displaced, or left homeless. By that organization's count we now have twice the number of disasters per year that we did 20 years ago.
Take the Haitian earthquake of 2010: measuring 7.0 on the Richter scale, it killed about a quarter-million people, with another 1.5 million displaced; a whopping $13.34 billion dollars was spent in aid. As it happens, a 7.0 also hit New Zealand later that year, followed by a much more destructive 6.3 aftershock in early 2011. Total deaths: 181. The key to the difference, of course, is that Haiti has about twice the population of New Zealand living in a tenth the space, and the buildings housing this population are of generally poorer quality—the lack of rebar and other structural reinforcement led to exponentially greater damage.
Comparing India and the U.S., it's a similar story: between 1980 and 2002 India had 14 major earthquakes killing 32,117 people, while the U.S. had 18 that killed only 143. And so on: a disproportionate share of the deaths caused by environmental shocks are borne by people in developing countries where population growth is greatest. According to the University of Colorado, roughly 403 million people live in places with significant seismic hazard. It only makes sense that the death tolls are increasing.
So yes, there are more disasters, and they're hitting us harder. This may not be entirely inevitable: Indian prime minister Narendra Modi, for instance, is pushing a seven-year, $2 trillion plan to build improved housing for 170 million citizens now living in slums. On the other hand, climate change will worsen as long as we continue to ignore it, as President Obama not-quite-jokingly pointed out at the White House Correspondents' dinner in April. At any rate, we're not likely to turn the more-catastrophes trend around soon. The fact that CGI is finally capable of realistically rendering all this stuff for summer-blockbuster audiences is small consolation, but for now it may be all we've got.
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