Coastal Growth, Not Global Warming, Blamed for Rising Storm Losses

A hurricane that hit Miami in 1926 would cause up to $157 billion in damage if it were to strike today, according to a recent study.

U.S. storm costs are rising because of higher populations and wealth on the coasts, not a spike in the number or power of hurricanes, the study said.

Its conclusions run counter to the notion that the $150 billion in damages caused by the destructive Atlantic hurricane seasons of 2004 and 2005 might be linked to global warming, which some scientists believe is behind a spate of extraordinarily powerful hurricanes in recent years.

An extrapolation of current trends “suggests a storm like the 1926 Great Miami Hurricane could result in perhaps $500 billion in damage as soon as the 2020s,” the study said.

Hurricanes and their destructive potential have become a key concern in global energy, insurance and commodities markets in the last decade. Scientists believe the Atlantic basin entered a new era of more frequent hurricanes around 1995, which could last 25 to 40 years.

The study found that the 1926 Miami hurricane would have caused the largest losses in history — $140 billion to $157 billion — if it struck today, accounting for inflation and massive building along the Miami coastline in the last 80 years.

That toll would have far exceeded the current costliest hurricane, Katrina, which killed 1,500 people when it swamped New Orleans and the Gulf of Mexico coast in 2005, causing $81 billion in damage.

“There is nothing in the U.S. hurricane damage record that indicates global warming has caused a significant increase in destruction along our coasts,” Chris Landsea, one of the study’s authors and a leading skeptic on the influence global warming may have on hurricanes, said in a statement.

The study looked at mainland U.S. hurricane damage from 1900 to 2005 and found that there was no trend of increasing damage. On average, hurricanes have caused about $10 billion damage yearly in the United States for the last 106 years.

About 85 percent of the damage is caused by what scientists call “major” hurricanes, Category 3, 4 or 5 on the five-step Saffir-Simpson scale of hurricane intensity, which feature sustained winds above 110 mph. Only 24 percent of cyclones that hit the United States are major ones.

The study estimated that because of inflation and coastal construction, the damage caused by the 1926 Miami hurricane would have measured $72 billion in 1995 and then jumped to as much as $157 billion just 10 years later.

Some risk analysts estimated damage tolls could be expected to double roughly every 10 years because of the increasing numbers of buildings, construction costs, and other factors.

“Unless action is taken to address the growing concentration of people and property in coastal hurricane areas, the damage will increase by a great deal as more people and infrastructure inhabit these coastal areas,” said Landsea, a researcher with the U.S. National Oceanic and Atmospheric Administration.

The study was published in Natural Hazards Review, a publication aimed at civil engineers.

(Editing by Eric Walsh)

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