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Hurricane Otis, Ciarán, and the Rise of Overnight Monster Storms

An unusual storm popped up in the Pacific in late October, though not a terrible lot was thought of it. On the 23rd, residents of Acapulco, Mexico, were told by forecasters to expect a gradually strengthening tropical storm that would make landfall on Wednesday. By Tuesday night, however, with virtually no change in the forecast, Hurricane Otis rapidly intensified from a minor storm to a record-shattering Category-4 hurricane–and it made landfall as the strongest Pacific hurricane to strike Mexico, at a Cat-5. One could have quite possibly fallen asleep thinking Otis was a minor inconvenience and woken up to a storm that generated what is potentially the strongest wind gust ever recorded from a hurricane, at 205mph. As of this writing, over 45 people were killed by Otis, with another 45 still missing.

The dangers of this kind of storm are impossible to overstate; outside of science fiction (and our own future, probably), a category-5 hurricane is the strongest storm–and one of the greatest collections of energy–possible on our planet. The reason we don't see brutal death tolls from storms like this in modern history is thanks to advances in forecasting, but no amount of forecasting is able to remedy the situation of a storm like Otis, in which a tropical storm with little threat to life becomes a record-breaking powerhouse in twelve hours. Imagine giving a city like New Orleans or Miami twelve hours to evacuate–you simply cannot expect a population of that size to up and depart successfully in that amount of time. For context, New Orleans received its first (voluntary) order to evacuate on August 27th, about 36 hours before Hurricane Katrina's landfall. A mandatory evacuation order was put into effect about 20 hours before landfall. For even more context, a 2004 FEMA drill estimated a complete evacuation of New Orleans would take over 72 hours.

Which brings me to the climate crisis, and the rise of rapidly intensifying storms. (Before we get there, I do have one minor note: despite being less than 250 miles from Acapulco, and the rain a Cat-5 storm can bring, Mexico City is suffering under a pretty terrible drought, and water restrictions have been put in place for one of the world's most populous cities. Don't you love that we live in a world where that's an aside in a newsletter about disaster preparedness?)

Rapid Intensification Rapidly Intensifies

Rapid intensification is the process under which storms (principally water-born cyclones but not always) gather an immense amount of energy in a small amount of time. This is generally due to the presence of warm oceanic waters in the storm's trajectory, which provide an easy source of energy for the storm. Warm water isn't the only source of rapid intensification, but it is the one you're most likely to see*.

There has been a big increase in the frequency of rapidly intensifying storms in recent history. The article linked above measured the period between 1982-2009, and even in that distant past the attribution of this rapid intensification was obvious–it's anthropogenic climate change. The article, written in 2019, lists the seven most rapidly-intensifying storms that made landfall on the US since 1950 up to that point, with four of the seven occurring since the turn of the century. However, just since that article's writing, three more storms would rank on that list. That is incredibly disconcerting.

This increasing frequency of rapid intensification events is not going away. While we are certainly primed at the moment for these intensification events thanks to incredibly warm oceans and El Niño, a subsequent La Niña is only going to temporarily alleviate these symptoms. (Ignoring, for the moment, that El Niño is supposed to decrease storm frequency and La Niña increase it). That's because, as a system, the Earth is only ever–at least for our lifetimes–going to continue to absorb more thermal energy than it gives off or reflects. This is just one more awful thing we get to deal with due to runaway climate change.

*While hurricanes thrive in warm conditions, storms occur all the time and under all kinds of conditions, of course. One of the other major creators of storm activity is atmospheric instability**–the increased likelihood of vertical motion of air in a given area, which can occur due to the collision of different fronts, currents, etc. You obviously don't need a warm ocean to have a snowstorm, for instance, but that will tend to occur at the confluence of cold air and warm, moist air, like most every storm.

**Technically speaking, this instability is the only cause of storms, but you get what I mean, right? Right.

Storm Ciarán

Days ago, a cold front swept across most of the United States, reminding me just how much I hate winter and eventually spawning a storm the likes of which Europe (less-and-less) rarely sees. This cold front rushed off the US coast and on eastward, pushed along by a particularly strong jet stream. The speed with which this storm moved consequently lowered the air pressure along with it, which consequently upped its local wind speeds. The result is a record-breaking storm that has caused over a million people in France to lose power, disrupted travel, and created 50 foot waves off the French coast. Seven people are reported dead and dozens injured. Ciarán is said to be the worst storm to strike France since 1987.

While Ciarán isn't the powerhouse that Otis was, it is a rare and powerful storm and a prime example of the new world we're living in–one in which a storm can spin up, overnight, in October, and wreak death and destruction. In its wake, another storm is already forming, though it is not expected to be as powerful. I've said it a hundred times before, but this is our new world. Weather forecasting has saved innumerable lives, but in an era of supercharged storms and rapid intensification, those forecasts are less reliable.

How This Shakes Out

The increase in rapidly intensifying storms in recent times is emblematic of the problems we are facing and will face more of as the climate crisis worsens. What's more, the loss of reliable forecasts is a not-too-terrible metaphor for our crumbling infrastructure and government mismanagement. All we need is for these storms to get racist and we'll have just about every angle covered.

But truly, without harkening to our generally darkening horizons, the rise in these storms in troubling and life-threatening in their own right. And it's not just freak coastal storms we have to worry about; as the world heats up, there will only ever be more energy available for these storms to crop up across the globe. While North America is in for a mostly mild winter due to El Niño, the potential for heavy snows and ice storms is ever-present, and one thing El Niño doesn't change is that warm air holds moisture better, meaning that when it does snow, it's likely to be heavier than normal. There's also, boringly, the insurance market to consider. As weather ramps up and costs rise, some housing markets will cease to be insurable, resulting in some rapidly intensifying decay of certain portions of vulnerable cities.

There's no escaping this issue, really. Whether they reach you physically or economically, rapidly-intensifying storms are weirdly emblematic of the hard times coming due to climate change. The best we can do, as with the problem at large, is brace ourselves and try to keep out of harm's way.