November 15, 2013 3:19PM

Was Typhoon Haiyan the Most Intense Storm in Modern History?

Global Science Report is a feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”

Global warming buffs have been fond of claiming that the roaring winds of Typhoon Haiyan were the highest ever measured in a landfalling tropical cyclone, and that therefore (?) this is a result of climate change. In reality, it’s unclear whether or not it holds the modern record for the strongest surface wind at landfall. 

This won’t be known until there is a thorough examination of its debris field.

The storm of record is 1969 Hurricane Camille, which I rode out in an oceanfront laboratory about 25 miles east of the eye. There’s a variety of evidence arguing that Camille is going to be able to retain her crown.

The lowest pressure in Haiyan was 895 millibars, or 26.42 inches of mercury. To give an idea, the needle on your grandmonther’s dial barometer would have to turn two complete counterclockwise circles to get there. While there have been four storms in the Atlantic in the modern era that have been as strong or a bit stronger, the western Pacific sees one of these approximately every two years or so.

Camille’s lowest pressure was a bit higher, at 905 mb (26.72 inches). At first blush it would therefore seem Haiyan would win the blowhard award hands down, but Hayian had a very large eye around which its winds swirled, while Camille’s was one of the smallest ever measured.  At times in its brief life, Camille’s was so small that the hurricane hunter aircraft could not safely complete a 360 degree turn without brushing through the devastating innermost cloud band, something you just don’t want to be near in a turning aircraft. In fact, the last aircraft to get into Camille, which measured 190mph sustained winds, lost an engine in the severe turbulence and fortunately was able to limp home.

Haiyan’s estimated 195mph winds were derived from satellite data, rather than being directly sensed by an aircraft.  But winds over the open ocean are always greater than those at landfall because of friction, and the five mph difference between the two storms is physically meaningless. 

The chance that an onshore anemometer (wind-speed and direction sensor) will survive such a storm isn’t very high, so the winds are inferred by scientists and engineers from the texture and distribution of what’s left behind.

Every year, our National Hurricane Center summarizes the Atlantic hurricane season in painstaking detail in article published in the prestigious journal Monthly Weather Review. Describing Camille’s destruction,  it said:

Maximum winds near the coastline could not be measured, but from an appraisal of splintering of structures within a few hundred yards of the coast, velocities probably approached 175 k[nots]. 

That’s 201 mph.(Higher winds have been measured on small islands. With Haiyan and Camille, we are talking about storms running into large landmasses, where friction takes place.)

Camille killed 143 along the Gulf Coast, while Haiyan’s toll is currently estimated to be more than 2,500.

The difference, which is more than an order of magnitude, is largely (but not completely) due to poverty. Despite experiencing roughly five landfalling tropical cyclones per year, Philippine infrastructure simply isn’t as sound as it is in wealthier countries. As a grim example, a number of Haiyan’s casualties actually occurred in government-designated shelters that collapsed in the roaring eyewall. 

In addition, the transportation infrastructure simply couldn’t handle a mass evacuation. If a similar situation applied to the U.S. Gulf Coast, Camille would have killed thousands at landfall, a fact noted in the Hurricane Center’s report on the 1969 season. Where Haiyan hit in the Philippines, there simply weren’t any roads capable of evacuating the citizens of Tacloban City safely inland, forcing them to ride it out dangerously close to the invading ocean and exposed to winds that pulverized most structures.

So, while we really don’t know which storm had higher winds, we do know that more affluent societies are much less affected by even the strongest storms. As Indur Goklany, (who writes frequently for Cato) has pointed out, if left to develop, the entire world will be much more resilient to climate change than it would be if the ineffective policies to “stop” it slowed economic growth.