I started this post intending to discuss the 10 worst earthquakes, and what that means for those living in earthquake country. As often happens, my brain chose to go in a different direction. I invite you to follow its path – “we” found a lot of fascinating disaster information!

2004 Indian Ocean Tsunami killed almost everyone on this train in Sri Lanka. Photo by James Gordon.
Ten Largest Earthquakes since 1900
1) 9.5 Chile 1960 1,655 killed
2) 9.2 Alaska 1964 128 killed
3) 9.1 Sumatra 2004 227,898 killed (mostly from large tsunami)
4) 9.0 Japan 2011 20,350 killed (mostly from large tsunami)
5) 9.0 Kamchatka 1952 2336 killed
6) 8.8 Chile 2010 550 killed
7) 8.8 Ecuador 1906 1,000
8) 8.7 Alaska 1965 7 killed
9) 8.6 Sumatra 2005 1300 killed
10) 8.6 Tibet 1950 1526 killed
My thoughts:
1) 4 of the 10 largest earthquakes happened in the last 8 years! Are giant earthquakes on the increase? Luckily, the U.S. Geological Society page “Are Earthquakes Really on the Increase?” reassured me that our ability to locate and communicate about earthquakes has improved, but actual earthquakes remain the same. In fact, in any given year the world can expect about 17 major earthquakes (7.0 – 7.9) and one great earthquake (8.0 or above). Reassuring? Not really!
2) I don’t want to live in Alaska, Sumatra, or Chile (6/10 of the largest earthquakes happened there)! But wait – not very many people died in Alaska despite giant earthquakes. Do deaths have anything to do with earthquake magnitude? This led to…
Ten Deadliest Earthquakes since 1900
1) 7.0 Haiti 2010 46,000 – 316,000 killed
2) 7.8 China-Haiyuan 1920 200,000 – 273,400 killed
3) 7.8 China-Tangshan 1976 242,769 – 779,000 killed
4) 9.1 Indian Ocean 2004 227,898 – 320,000 killed
5) 7.9 Japan, Kwanto 1923 105,385 – 142800 killed
6) 7.1 Italy-Messina 1908 60,000 – 123,000 killed
7) 7.3 Turkmenistan 1948 10,000 – 176,000 killed
8) 7.9 Peru 1970 70,000 – 100,000 killed
9) 7.9 China-Sichuan 2008 68,000 – 87,587 killed
10) 7.6 Pakistan 2005 75,000 – 100,000 killed
My thoughts:
1) Why such widely varying death reports – off by thousands (and for all disasters – not just earthquakes)! This one took some research. Some numbers include only people killed from the primary disaster (eg. things falling down in earthquakes), while others include secondary causes (eg. fire or tsunami). Missing are often lumped with dead, but some are really just displaced. Body counts don’t work because not all bodies are found. Official government numbers are the worst! They base numbers on inaccurate census information, or even worse, skew statistics for political purposes. Falsely high fatalities can earn more foreign aid and donations, whereas falsely low fatality rates hide government failures in preparation or response. And don’t forget the media! Initial media reports are wildly inaccurate. While understandable, their numbers are rarely corrected when better information becomes available. Incorrect media numbers seem to persist forever.
My final take on death statistics – It’s impossible to know the number killed in some disasters. You can estimate hundreds, thousands, ten thousands, or hundred thousands, but that’s about it!
2) Earthquake magnitude obviously correlates poorly with mortality – 9 of the 10 deadliest were only in the 7.0-8.0 range. Maybe I shouldn’t worry so much about our potential Pacific Northwest 9.0 earthquake! Or should I worry more? If we die, preparedness doesn’t matter. It’s when we survive that preparedness becomes crucial.
3) If it isn’t earthquake magnitude, what causes high earthquake fatality rates? …..

Population Density of China (year 2000) – location of multiple deadly earthquakes. Photo by SEDACMaps.
Ten Reasons for Increased Earthquake Fatalities (my list – not in any statistical order):
1) Population density – earthquakes in rural areas kill fewer people (duh!)
2) Coastal location and risk of tsunami – think 2004 Indian Ocean and 2011 Japan
3) Uncontrolled fires – the 1923 Japan earthquake killed 140,000 from fire alone!
4) Building construction and age – older masonry buildings collapse
5) Soil characteristics of building areas – consider liquefaction near lakes, bays, some rivers
6) Socioeconomics of affected country – because of far too many reasons to list
7) Time of day – are people home vs in schools, churches, etc.?
8) Landslides – particularly in deforested areas
9) Post-earthquake disease, famine, and exposure – the measure of your disaster response
10) Preparedness – building retrofits, trained response, medical care (I had to throw preparedness in)
Now for a side thought from the deadliest list – the United States isn’t on here! How do we stack up compared to the rest of the world when it comes to deadly natural disasters?
Ten Worst United States Natural Disasters since 1900
1) Galveston Hurricane 1900 8000 killed
2) San Francisco Earthquake 1906 3400 killed
3) Okeechobee Hurricane 1928 2500 killed
4) Hurricane Katrina 2005 1,836 killed
5) Atlantic Gulf Hurricane 1919 772 killed
6) Great New England Hurricane 1928 700 killed
7) Tri-State Tornado 1925 700 killed
8) Dust Bowls 1930s 7000 killed
9) United States Heat Wave 1988 4,800 to 17,000 killed
10) United Stated Heat Wave 1980 1,700 killed
11) Chicago Heat Wave 1995 750 killed
My thoughts:
1) The United States has very few deadly natural disasters. I couldn’t come up with 10 since 1990 that really qualified as deadly, and even these are not in the same ballpark as the deadliest global natural disasters.
2) The most deadly natural events in the United States are not things we routinely consider disasters. They are actually heat waves, drought, and dust bowls. Although not listed, we’ve also had some relatively deadly cold weather. Given climate changes, does anyone see a problem approaching?
3) If our disasters are “small”, why do they get so much press, even in the rest of the world? Could it be (shock and horror) money?
Ten of the World’s Costliest Disasters (Total Economic Cost)
1) Honshu Earthquake, Japan 2011 $230 billion
2) Sichuan Earthquake, China 2008 $147 billion
3) Hanshin Earthquake, Japan 1995 $144 billion
4) Hurricane Katrina, United States 2005 $137 billion
5) Irpinia earthquake, Italy 1988 $52 billion
6) Northridge Earthquake, United States 1994 $43 billion
7) Hurricane Andrew, United States 1992 $41 billion
8) Chūetsu earthquake, Japan 2005 $32 billion
9) Hurricane Ike, United States 2008 $30 billion
10) İzmit Earthquake, Turkey 1999 $26 billion
My thoughts:
1) Tracking down disaster cost is even harder than tracking down fatalities. Following lots of initial estimates, there is very little looking back and adding it all up after “recovery”. I checked “money sites” – MSN Money and The Economist for example – to come up with my numbers, but I don’t guarantee they are correct.
2) If you are poor, you don’t cost much. Despite their size, the economic cost of Haiti’s 2010 earthquake and the 2004 Indian Ocean earthquake/tsunami were each estimated only between $8 and $14 billion. When the worth of your country is low (land value, income, etc.), losing hundreds of thousands of people doesn’t put much of a ripple in world economy.
3) The United States has 4 in the top 10 most expensive disasters. We don’t lose many people, but it sure costs a lot to rebuild our communities to their previous condition.
4) In 2011, there were 14 separate $1 billion-plus weather events in the United States, with losses topping $60 billion. In 2012, Hurricane Sandy alone will probably approach this, despite being quite “small” on the global scale of natural disasters. How will we deal with steadily increasing disaster costs?
I hope you enjoyed my list “wandering”. As always, the more I learn, the more I question. Some of these topics clearly need an entire blog post sometime. Stay tuned!
Stay safe,
Sheila Sund, M.D.