In a changing climate, hurricanes like Ida are stretching our imagination

It’s hard to imagine something you’ve never experienced, and that may help explain 2021’s lethal Atlantic hurricane season. One of the challenges of climate change is that it is going to continue to throw at us conditions that we have never seen before. The lesson of Hurricane Ida — and indeed this whole summer of 2021 — is that the gap in our imagination is dangerous.

Ida should be an example of how much we know about weather. Three days before landfall in Louisiana, Ida was a ragged tropical storm that barely deserved a name. At that time, meteorologists predicted that Ida would quickly intensify into a strong hurricane as it encountered remarkably warm water in the Gulf of Mexico.

Weather models accurately predicted Ida’s path across the Gulf of Mexico and then its arcing trajectory across the eastern half of the country. People in its path were told what to expect, because the models also did an amazing job predicting conditions, including intense rains in New Jersey and New York when Ida’s tropical moisture collided with an intense cold front.

But too many of us couldn’t imagine those conditions. When I moved to New Jersey this winter, I couldn’t imagine having to spend an evening with four dogs, three humans and two cats in the basement waiting out a tornado warning. A few miles to the north of us, others were struggling with conditions that were even harder to imagine as walls of water swept people away in their cars and trapped residents in their apartments.

My mind keeps going back to the horrific basement apartment flood scene in the 2020 Oscar-winner “Parasite.” This scene is hard to watch. But that’s important: imagining these uncomfortable scenarios is a key prerequisite for avoiding them. The rate of rainfall — over 3 inches per hour in New York City and the total rain — over 8.4 inches in Newark eclipsed the past experience in this region, even compared to past storms like Hurricane Sandy. Many people in New Jersey and New York had little frame of reference for rains that could sweep cars off of roads. 

In New Orleans, though, Ida showed how our experience with previous storms can save lives. Hurricane Katrina led to an expanded network of levees that saved the city from catastrophic flooding this year. But even as defenses held and new buildings kept people safe during hurricane-force winds, the challenge quickly turned to imagining life during a heatwave in a city without power. Hurricane-safe places became sweltering saunas when record-setting heat arrived. More people died from heat than from the initial landfall of the storm.

We might struggle to imagine the continually novel world of climate change, but we don’t lack the knowledge. The 2021 hurricane season, and especially Ida, is also an example of how much we can predict. We know, for example, that rapidly intensifying major hurricanes are more common in a world with high carbon dioxide, which traps heat on our planet. Much of that extra heat is stored in the ocean, which as Ida demonstrated, feeds hurricanes. And we know that intense rainfall is more common, too. One of the fundamental relationships in meteorology is that a warmer atmosphere can store more water vapor, leading to more events like the big rains that we saw during Ida.

Our experience with Ida shows both the possibilities and also the limitations of adapting to climate change. We are capable of learning from past experience. With significant investment, we can make cities that keep people safe and bounce back quickly from storms. Sadly, we do not always do this, leaving people vulnerable to extreme conditions that are becoming increasingly common. But climate change will continue to give us extreme weather events and will subject us to conditions we’ve never seen before. These novel conditions are particularly challenging, for individual citizens who must respond in the moment, for officials who must plan and budget and coordinate responses to unprecedented events, as well as for decision-makers who must develop and enforce policies that keep people safe.

Climate science tells us that we will keep encountering conditions we’ve never seen before — hotter weather, bigger rains and more compound events. Keeping people safe and making communities more resilient will require us to imagine what these new conditions will mean and then act accordingly. Otherwise, the consequences will be, well, unimaginable.

Andrew Pershing is the director of Climate Science at Climate Central. He is an expert on how climate trends and events impact ecosystems and people and recently led the Oceans and Marine Resources chapter of the fourth U.S. National Climate Assessment. Follow him on Twitter: @Sci_Officer