The catastrophic flooding that devastated Louisiana last month, claiming 13 lives and displacing thousands, has been described as the worst U.S. natural disaster since Hurricane Sandy in 2012.
But what if these so-called “once-in-a-lifetime” disasters are no longer so rare?
According to new research from the U.S. National Oceanic and Atmospheric Administration (NOAA), human-caused climate change has increased the likelihood of such extreme downpours by at least 40%.
Even more alarming, scientists suggest that this might actually be a conservative estimate—the true risk could be nearly twice as high as it was a century ago.
“We found human-caused, heat-trapping greenhouse gases can play a measurable role in events such as the August rains that resulted in such devastating floods, affecting so many people,” says Karin van der Wiel from NOAA’s Geophysical Fluid Dynamics Laboratory.
No Longer a Rarity
The NOAA researchers used advanced climate models and historical rainfall data to compare the likelihood of severe three-day downpours now versus a century ago.
The results? A dramatic shift in the odds of these extreme events.
A century ago, Louisiana could expect a storm of this magnitude approximately once every 50 years.
Today, thanks to climate change, a similar storm is likely to occur every 30 years—a significant increase in frequency.
And it’s not just the frequency that has changed. The intensity of these storms has also increased.
A storm that might have produced a certain amount of rainfall in 1900 now delivers 10% more rain due to higher atmospheric moisture levels.
More rain in a shorter time means a greater risk of flash floods, overwhelmed drainage systems, and widespread devastation.
The Surprising Science Behind the Downpours
At first glance, the Louisiana floods might seem like an isolated disaster.
But in reality, they are part of a broader pattern of intensifying storms linked to climate change. Why? Because warmer air holds more moisture.
“The moisture component is where climate change comes in—warmer air can hold more water vapor,” explains Angela Fritz for The Washington Post.
“As the air warms due to greenhouse gas emissions, the air gets more humid, and there’s more moisture that generates more rain.”
In Louisiana’s case, a stationary low-pressure system combined with extreme humidity to produce unprecedented rainfall.
The result? A staggering 26.9 trillion liters (7.1 trillion gallons) of water poured down—three times the amount dumped by Hurricane Katrina.
More than 30,000 people had to be rescued, over 60,000 homes were damaged, and the economic toll is expected to reach $9 billion.
Challenging the “Natural Disaster” Narrative
For years, extreme weather events like these have been called “natural disasters.” But is that term still accurate?
If human-caused climate change is significantly increasing the risk of catastrophic floods, then these disasters are not purely natural—they are at least partly engineered by our own actions.
The carbon emissions from industries, vehicles, and deforestation are shaping the storms of tomorrow.
This shift in perspective is crucial. If we continue to see these floods as unavoidable acts of nature, we fail to recognize our ability—and responsibility—to reduce their impact.
Cutting greenhouse gas emissions, investing in resilient infrastructure, and reforming urban planning strategies can make a significant difference in mitigating future disasters.
The Growing Cost of Ignoring Climate Science
Each time a new extreme weather event occurs, the cost of inaction becomes clearer.
The Louisiana floods are just one example of how climate change is pushing our cities and communities to the brink. Without urgent action, we can expect:
- More frequent and intense hurricanes
- Longer and more severe heatwaves
- Rising sea levels leading to coastal flooding
- Increased risk of wildfires
The research conducted by NOAA is still undergoing peer review, but its findings align with global climate models that predict a future of more intense storms.
The evidence is mounting, and the stakes are too high to ignore.
Understanding and Adapting
If there’s a silver lining in all of this, it’s that our understanding of climate change is improving.
By studying past and present weather patterns, scientists are helping communities prepare for what’s ahead.
“Researchers, communities, and businesses alike see the value in these analyses,” says Monica Allen of NOAA.
“They help us grapple with what has happened and strengthen our ability to stay resilient to future events.”
So, what can we do?
- Reduce carbon emissions by transitioning to renewable energy sources.
- Invest in climate-resilient infrastructure to withstand severe storms.
- Improve urban planning by avoiding construction in flood-prone areas.
- Support climate policies that promote sustainable development and disaster preparedness.
Extreme weather is no longer a distant threat—it is here, reshaping our world in real-time.
The question is not whether we can stop it entirely, but whether we can adapt fast enough to survive it.