Europe, Africa, North Carolina Flooding: Once-in-a-lifetime floods are becoming routine

Can a flood be called a thousand-year flood if it happens every five years?

That’s a question worth asking this week in the southern US, central Europe and central Africa after the latest round of biblical deluges that are becoming increasingly routine and destructive as the planet heats up. They’re reminders that climate change is no longer a problem for our grandchildren — unless those grandchildren happen to be living in our flooded basements. Regardless of location or economic development, we are ill-prepared for the consequences.

Earlier this week, a tropical storm so mediocre that it didn’t even merit a name hit the southern coast of North Carolina, around Wilmington, dumping 18 inches of rain in 12 hours. Meteorologists say this sort of event has a 1-in-1,000 chance of happening in any given year; something more commonly known as a “thousand-year flood.” But the moniker doesn’t quite fit when you consider similar disasters also hit the area in 1984, 1999, 2010, 2015 and 2018. Along with the latest flood, that’s five in just 25 years.

Despite lacking a name, the rainstorm may have caused five Septembers’ in damage, private meteorological service AccuWeather estimated. Not counting that, there have been 20 extreme-weather events in the US so far this year wreaking $1 billion or more in damage, according to the National Oceanic and Atmospheric Administration, making it already the third-busiest year on record, with half of a hurricane season still to go.

Most of these disasters have basically been thunderstorms on steroids, causing damaging rain, hail and wind across a swath of the central US from Texas to Michigan. And they don’t include cheaper but still-catastrophic deluges in Florida, Vermont and elsewhere.

The issue is that hot air is thirsty air, capable of soaking up water and then dumping it in torrential sheets when the conditions are right. The atmosphere can hold 7% more moisture for every 1 degree Celsius it warms. The planet has so far warmed about 1.3C above preindustrial averages on its way to 3C at our current pace of spewing greenhouse gases. These deluges are just a taste of what’s to come if we don’t quit fossil fuels more urgently.

But they are more than destructive enough already. A swath of sub-Saharan Africa this month suffered the heaviest rainfall in its history, causing flooding that has taken 1,000 lives, driven millions from their homes and wreaked havoc on an already dangerously stretched food supply. It’s part of a bizarre weather pattern that’s even making it pour in the Sahara, with rain falling at a pace occurring “roughly once in several thousand years,” according to the weather blog Severe Weather Europe.

The blog pointed to a 2023 study in the journal JG Atmospheres tying Saharan rainfall to heated water in the Atlantic Ocean and the Mediterranean Sea. In other words, by heating up the oceans, climate change appears to be making it rain in the driest place on Earth.

The unusually warm Mediterranean also helped fuel the rains inundating central Europe this week, in places dumping five Septembers’ worth of water in a few days. At least 20 lives have been lost and billions of dollars in damage incurred, and the floodwaters are still rising on the Danube River.

Bloomberg News notes that Poland, the Czech Republic and other European countries have invested in flood defenses in recent decades, but they weren’t enough to avert disaster. These and other wealthy countries, including the US, will have to increase their drainage and reservoir systems to handle heavier downpours that are becoming increasingly routine. They’ll need to prioritize wetlands and floodplains over impermeable surfaces that don’t let water seep into underground aquifers. They’ll need to weatherproof homes, roads, bridges and other infrastructure.

Developed nations must also help developing nations keep these rains from escalating from mere disasters to mass tragedies like the one unfolding in Africa. As noted by scientist Friederike Otto — a pioneer in attributing extreme weather to climate change — these catastrophes are amplified when they happen to already fragile societies.

Rich nations have pledged $100 billion a year to help poorer ones mitigate and adapt to climate change. What’s really needed is more like $500 billion a year, according to the UN’s Standing Committee on Finance. Canceling or restructuring their staggering debt burdens would go a long way toward that goal. We’re looking at you, too, China.

No matter where we are or whether we run a government or a household, we all need to question our own readiness for the next routine rainstorm that becomes a life-changing event. The climate crisis is not a thousand-year or even hundred-year problem. It has already started.

Credit: Bloomberg