Is Average Hurricane Strength on the Rise?
I read an interesting article from the Guardian the other day that focused on the question of whether average hurricane strength is increasing because of climate change. I, for one, certainly hope not, as this will only serve to make emergency preparedness more difficult. Unfortunately, the reality does not appear to match my hope!
How is Hurricane Strength Measured?
Hurricane season runs from June 1 to November 30, peaking from August to October.
Hurricanes are essentially wind towers, sometimes exceeding 60k feet tall, that typically form in the Atlantic Ocean when water temperatures are warm (hurricanes formed over the Pacific Ocean are called typhoons and those that form over the South Pacific and Indian Ocean are called cyclones). The storms feed off the ensuing moisture and gain strength as long as they are not impeded by dry air or a landmass.
Hurricane strength is measured on a scale of 1-5 by the Saffir-Simpson scale. In general, hurricanes are named once their sustained wind speed reaches at least 40 miles-per-hour. A category-3 hurricane, which has wind speeds of over 110 miles-per-hour, is considered a major hurricane. The highest category – category-5 – has sustained wind speeds of over 157 miles-per-hour. Hurricane Michael in 2018 was the first catrgory-5 hurricane to make landfall in the US since 1992.
Is Hurricane Strength Increasing on the Heels of Climate Change?
It’s no secret that the severity of hurricanes has been greater than historical averages over the last few years, mainly because their intensity has ramped up more quickly than storms of the past. In fact, according to research published in Nature Magazine, the percentage of tropical storms intensifying into hurricanes has tripled over the last 3 decades. Additionally, a record $135 billion was paid by insurance companies in 2017 for hurricane damages.
The bottom line is that most experts agree that climate change is causing average hurricane strength to increase over time. For example, the United Nation’s Panel of Climate Change predicts that average hurricane strength will increase by 5% by the end of this century. The magnification factors include more moisture in the atmosphere, warming ocean temperatures, and rising sea levels.
From a utility emergency preparedness perspective, this is obviously not great news, but at least these projections are well documented. The expectation has been set, and this should serve as an early warning for what’s to come. There’s little doubt that emergency response plans and protocols will need to be tweaked in the years and decades to come due to the ‘new norm’ of higher average hurricane strength.
