Hurricane Helen made landfall on Friday, September 27th A Category 4 storm in Florida then moved inland, bringing heavy rainfall and subsequent flooding. Predictably, many media outlets immediately rushed to blame this particular storm and its devastation on climate change. These statements are all wrong. Data show that hurricane activity over the past 50 years has shown no climate signal of worsening intensity or more frequent hurricanes. Additionally, historical records show that flooding similar to what occurred during this storm has occurred in the same area before.
This is the second time this week climate realism This particular storm is being reported, but the media’s claims are so broad that they deserve to be debunked multiple times. Here are some examples of titles. “The Hill” wrote: “How climate change is exacerbating storms such as Hurricane Helene.” Yahoo News claimed that “Helen shows that hurricanes in the era of climate change will not only damage coastlines,” but The Guardian “‘No place is safe’: Fractured Asheville shows the alarming impact of the climate crisis.” Associated Press (AP) chimed in, “Heron and other storms dumped up to 40 trillion gallons of rain across the South.” Even Tampa, Florida, Mayor Jane Castor joined in on the climate alarm “I don't know anyone who can deny the absolute impact that climate change has on the storms that we're experiencing,” he declared in an interview with CNN.
All of these claims ignore actual data and historical records. They also ignore unique meteorological (rather than climatic) conditions that could lead to more rainfall and flooding.
The first thing to note is that weather events are not climate events. Weather operates on a very different time scale than climate.
Second, the suggestion that climate change is worsening storms like Helen simply doesn’t hold up when examining actual data. For example, meteorologist Dr. Ryan Maue, quoted in the AP story mentioned above, maintains a running chart of “Cumulative Cyclone Energy” that tracks how much energy is actually in a hurricane on a month-by-month basis, seen in Figure 1 below, updated to 2024.
He writes on his research page:
Tropical cyclone accumulated cyclone energy (ACE) has shown striking global interannual variability over the past 40 years. Five degrees since 2006, northern hemisphere and global tropical cyclone ACEs have dropped sharply to levels not seen since the late 1970s. In addition, the frequency of tropical cyclones has dropped to an all-time low.
That's all the Tampa mayor said, “I don't know how anyone can deny the impact of climate change on the sheer power of the storms we're seeing right now.” Actual data disproves your claim.
If climate change was actually making storms like Helen more powerful, it would show up on the ACE chart, but that's not the case.
Furthermore, meteorological science shows no connection between climate change and hurricanes. A page on the topic maintained by the National Oceanic and Atmospheric Administration (NOAA) Geophysical Fluid Dynamics Laboratory clearly states that there is no strong evidence to support such claims:
Finally, climate science itself shows that there is no correlation between climate change and hurricane intensity or frequency. Table 12.12 in Chapter 12 on page 90 of the Sixth Assessment Report of the United Nations Intergovernmental Panel on Climate Change (IPCC). The occurrence of climate impact drivers (CIDs) at different times does not show any current or future correlation. The colors in the table correspond to the confidence in areas with the highest confidence: white indicates where evidence of a climate change signal is lacking or non-existent, resulting in an overall lower confidence in emerging signals. Note the colors of the tropical cyclones in the table screenshot below:
As mentioned in the AR6 WG1 report “Climate Overview: Hurricanes” released by the IPCC in August 2021, the IPCC stated that “determining past trends in TCs [tropical storm] Metrics remain a challenge,” a statement that essentially acknowledged that scientists have yet to identify a reliable, measurable upward trend in the data.
It seems easy for the media and uninformed politicians like Tampa Mayor Castor to forget the recent past. The United States has not had a major hurricane (Category 3 or above) make landfall in more than a decade (2005 to 2017). This is the longest period in American history. Such dry hurricanes would be unlikely if climate change worsened them.
Clearly, despite the media hype, data, science, and history all show that their claims about the impact of climate change on hurricanes are simply untrue.
But what about the suggestion that the massive rainfall and subsequent flooding in Helen was caused by climate change? Meteorologist Chris Matz gave A complete analysis of weather events on Twitter. Some excerpts:
I'm going to take a moment to explain the meteorology behind the flooding in North Carolina [and Tennessee]. Analysis of precipitation in the past two days [from 12z today] It was revealed that more than a foot of rain has fallen in the Appalachian Mountains. Such heavy rainfall in such a short period of time will result in widespread rainfall regardless of the land topography. [and often devastating] submerged.
You'll see 14-18 inches of rainfall. [purple / pink contours in the image below] Along the Eastern Slope of the Blue Ridge [mountains] This is because of the orographic lift enhanced by strong mountain ranges. [in the second figure below] As moist air masses in the Helen Belt rotate counterclockwise through the region, they dynamically rise over sloping terrain to a state of supersaturation, causing excess steam to condense and precipitate. On the lee side of Tennessee, rainfall totals are lower due to some rain shadow effect due to downslope flow. This is what happens almost every day in the Hawaiian Islands.
As a result, a combination of storms and local topography resulted in consistent rainfall levels in the mountains near Asheville, North Carolina. Climate has nothing to do with it.
And, history tells us that the type of heavy rains that caused flooding around Asheville, North Carolina, has happened before. Here are some photos from newspaper reports and photos from Asheville, NC on July 17tha major flood event occurred in 1916:
The challenge for the media and politicians is to explain why Asheville had such a catastrophic flooding event before climate change became an issue, yet the amount of carbon dioxide in the atmosphere (which is said to exacerbate climate change and resulting storms) Much lower than today.
They can't. Instead, they prefer to cling to a popular narrative that the “climate crisis” caused the storm and subsequent damage, rather than focusing on data, science and history to the contrary. This is Big mistake, Beyond simple ignorance, this is journalistic and political malfeasance.
Anthony Watts
Anthony Watts is a senior fellow in environment and climate at the Heartland Institute. Since 1978, Watts has been in the weather business both in front of and behind the camera as a live television meteorologist and currently oversees daily broadcast forecasts. He created television weather graphics presentation systems, professional weather instruments, and co-authored peer-reviewed papers on climate issues. He runs the world's most viewed climate website, the award-winning wattsupwiththat.com.
Originally published in ClimateREALISM
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