According to the Centre for Research on the Epidemiology of Disasters (CRED), 60 percent of human deaths caused by natural disasters in the past decade have been due to earthquakes. This trend is not surprising, as populations in the world’s earthquake zones are skyrocketing. Eight of the most populous cities on Earth are built on tectonic fault lines, including Tokyo, New York and Mumbai. “There will be a big earthquake this century that will kill a million people,” says geology professor Nick Eyles. “You can be absolutely certain about that.”
Here is a list of densely populated cities at risk:
Kathmandu, Nepal Population: 3,000,000. It lies in the shadow of the Himalayas—the result of India pushing relentlessly into Asia in a battle of tectonic titans. Poorly constructed apartments are built on soft sediments easily disturbed by seismic shaking. The main airport through which relief efforts would be funnelled is also at risk.
Istanbul, Turkey Population: 13,255,000. This ancient city is waiting for the inevitable: a major earthquake along the North Anatolian Fault. Seismic activity is moving westward along the fault toward Istanbul—a well-known pattern of behaviour in the past. Old masonry buildings dot densely populated narrow streets. Parts of the coastline are also threatened by tsunami.
Manila, Philippines Population: 11,553,000. Manila is ill prepared to cope with the next major earthquake, estimated to kill 35,000 people, wreck 175,000 properties and leave hundreds of thousands homeless.
Jakarta, Indonesia Population: 26,600,000. As it sits just above the great Sumatran subduction zone, where the Indo-Australian plate slides below the Eurasian plate to the north, there is always a risk of strong earthquakes (and volcanic eruptions). But an absence of major quakes in Jakarta in recent memory has created a false sense of security.
Tokyo, Japan Population: 35,676,000. Some 30 million live or work in an area designated as high-risk. Recent events in Japan, which is supposedly better prepared than most countries, tell us that each new earthquake presents new challenges, even in economically advanced societies.
Mexico City Population: 8,851,000. Because it was built on an old lakebed, the very foundations of this city are at risk from severe shaking. The effects of the last quake in 1985 showed that many buildings cannot cope when earthquakes stir up soft sediment beneath them.
Delhi, India Population: 18,917,000. This sprawling city is crisscrossed by deeply buried faults that are poorly understood but have been reactivated as India ploughs northward into Asia. In the headlong rush for economic and urban growth, Delhi is poorly prepared for disaster. Mumbai and Kolkata share the same risks.
New York area, U.S. Population: 18,897,000. Surprising to some, but earthquakes in 1638, 1661, 1633, 1737, 1884 and 1944 warn of the risk. The area shares with Montreal and Ottawa the faults created when the North Atlantic Ocean opened 200 million years ago and Europe broke away from North America. These old faults are stretched to breaking point by ongoing westward movement of the North American plate.
Vancouver, B.C. Population: 2,117,000. Vancouver is built on soft, wet sediment of the Fraser River delta. “Liquefaction” will be the killer here in the next big quake generated along the Cascadia subduction zone. The effects could be devastating to Canada’s only major West Coast port and the nation’s economic lifeline to Asia.
Shanghai, China Population: 23,019,000. In 1980 there were no skyscrapers in Shanghai; now there are three times as many as in New York. China’s enormous, rapidly growing cities have experienced the biggest migrations of people in history but are cursed by their tectonic setting, built as they are on crust that is escaping the giant Himalayan collision zone between Asia and India. No amount of urbanization will let China escape its tectonic destiny of large earthquakes and loss of life.
Los Angeles, California Population: 15,250,000. Often overshadowed by discussion of the northern San Andreas Fault at San Francisco. The last major quake along the southern San Andreas was in 1857, when barely anyone lived here and few noticed. New studies reveal that L.A. is overdue, and this time it will be for real (i.e., not of the Hollywood variety).
Note: Population figures pertain to metropolitan areas.