US Hurricanes 2025 in Review

Five Figures - November 2025, and a Climategate Story

Attribution — Protecting the homeland!

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For the first time in a decade, the continental United States experienced no hurricane landfalls.¹ Islands in the Caribbean saw multiple landfalls, notably Hurricane Melissa’s landfall as a Category 5 storm in western Jamaica, which resulted in more than 100 deaths in the region and about $10 billion in losses.

The usual media script was played — Atlantic hurricanes and their impacts were attributed to “climate change” whereas the lack of damaging US landfalls was chalked up to “luck.” I posted on this — only partly tongue-in-cheek — during the peak of the hurricane season:

Extreme Non-Event Attribution

Today I share five figures that summarize some key elements of the 2025 U.S. hurricane season (and tropical cyclones globally). Early in 2026, Ryan Maue² and I will continue our annual global updates, with a more comprehensive analysis.

To encourage you to read the whole post, I end today with a sordid story about how our hurricane research was kept out of an IPCC assessment by IPCC leaders who found our peer-reviewed work inconvenient. We came out OK two decades later.

But first, 2025 hurricanes . . . starting with some interesting tidbits:³

• For the North Atlantic overall, 2025 saw the most ACE-per-hurricane — ACE is Accumulated Cyclone Energy, which integrates frequency and intensity — since 1932. Even though there was a near-average storm total (13), three developed into high ACE-producing Category 5 hurricanes.

• Globally, however, even with the high ACE-per-hurricane in the North Atlantic, 2025 will end below average (since 1971) for total ACE and ACE per hurricane (more on that below).

Let’s next look at some data.

The figure below shows the count of all (continental) U.S. hurricane landfalls 1900 to 2025. There is a lot of variability and obviously no upward trend.

The next figure shows, for the same period, landfalls of major hurricanes — That is, at Category 3 or higher strength on the Saffir/Simpson scale. There is also no upward trend in this time series. The most remarkable feature is perhaps the 11-year major hurricane “drought” from 2006 to 2017.

The figure below provides a (rough) update to our time series of normalized U.S. hurricane damage from 1900 to 2025, based on Weinkle et al. 2018.

A normalization seeks to estimate how much damage historical hurricanes would cause under contemporary societal conditions. The 21st century has seen large loss years, not unlike the first half of the 20th century.

Jessica Weinkle⁴ and I are in the process of updating the time series comprehensively and hope to have that published in 2026. Our preliminary results indicate a big jump up from the values in the figure below — owing in part to the significant recent inflation. Stay tuned.

Here is where things get really interesting: The figure below shows global ACE 1980 to 2024.⁵ There is obviously no upward trend in this time series.

The figure below shows global ACE per hurricane, also with no trend.

That lack of trend challenges a popular hypothesis — Specifically, that changes in climate will result in fewer storms, but a greater proportion of them will be of higher intensities. As a matter of simple math, both fewer storms (the denominator in ACE/hurricane) and greater per-storm intensities (the numerator) should result in an increase in ACE per hurricane.

While such a trend might emerge in the data in the future, to this point it has not.

Finally for today — this month marks 20 years since the publication of our paper:

Pielke Jr, R. A., Landsea, C., Mayfield, M., Layer, J., & Pasch, R. (2005). Hurricanes and global warming. Bulletin of the American Meteorological Society, 86(11), 1571-1576.

I collaborated with four NOAA scientists, including the director of the National Hurricane Center at the time, to produce a concise summary of the current (2005) scientific consensus on hurricanes and climate change.

Our cautious conclusion was in-line with the general consensus of the relevant community of experts and the Intergovernmental Panel on Climate Change:

To summarize, claims of linkages between global warming and hurricane impacts are premature . . . While future research or experience may yet overturn these conclusions, the state of the peer-reviewed knowledge today is such that there are good reasons to expect that any conclusive connection between global warming and hurricanes or their impacts will not be made in the near term.

After the paper was peer-reviewed and accepted for publication, however, there was a furious (but failed) effort to prevent its publication.

Instead, those seeking to halt its publication were given a chance to publish a response to our paper. They seemed upset more with the idea of our review (and us) than its actual content:

The climate is in the process of a rapid warming, caused in part by human activities, including emission of greenhouse gases (GHGs) and aerosols, and changes in land use (Houghton et al. 2001; Karl and Trenberth 2003). These climate changes may well be changing the properties of tropical cyclones, yet the potential relationships between climate change and tropical cyclones and the consequences for humans have been downplayed or dismissed by a number of recent articles, testimonies, and press releases (e.g., Michaels et al. 2005; Pielke et al. 2005; Mayfield 2005).

Anthes, R. A., Corell, R. W., Holland, G., Hurrell, J. W., MacCracken, M. C., & Trenberth, K. E. (2006). Hurricanes and global warming—Potential linkages and consequences. Bulletin of the American Meteorological Society, 87(5), 623-628.

We replied directly to their response in a rejoinder, opening our rejoinder by emphasizing that responding in the literature (rather than trying to halt publication) was the appropriate response:

We appreciate the effort taken by Anthes et al. (2006) to respond to our paper “Hurricanes and global warming.” Such open exchanges can help to clarify not only different perspectives on science, but also different perspectives on the structure and function of scientific assessments of peer-reviewed literature.

Pielke, R., Landsea, C., Mayfield, M., Laver, J., & Pasch, R. (2006). Reply to “Hurricanes and global warming—Potential linkages and consequences”. Bulletin of the American Meteorological Society, 87(5), 628-632.

I think that we clearly got the better of that exchange, but you can judge for yourself and discuss in the comments.

Here is what NOAA’s GFDL states (as of this month):

In summary, it is premature to conclude with high confidence that human-caused increases in greenhouse gases have caused a change in past Atlantic basin hurricane activity that is outside the range of natural variability, although greenhouse gases are strongly linked to global warming. . . We conclude that the historical Atlantic hurricane data at this stage do not provide compelling evidence for a substantial greenhouse warming-induced century-scale increase in: frequency of tropical storms, hurricanes, or major hurricanes, or in the proportion of hurricanes that become major hurricanes.

A postscript — Our 2005 review paper turned up in the release of the Climategate emails.

In those emails Phil Jones and Kevin Trenberth (who tried to prevent publication of our paper) chat over email about how they would ensure that our paper would not make it into the IPCC report that they were then helping to write.

Here is their exchange:

Jones to Trenberth on 22 June 2005:⁶

Kevin,

I’ll read the Pielke et al piece for BAMS that came over the skeptic email today. Presumably we’ll get forced to refer to it [in the 2007 IPCC report].

Trenberth replies:

Don’t see why we should refer to the Pielke piece. It is [n]ot yet published. It is very political and an opinion.

Jones soon comes around, despite noting its peer-reviewed status:

Kevin,

Read the article on the new patio at home with a glass of wine. I thoroughly agree that we don’t need to refer to it. Wrote that on it last night. It is very political. Several sentences and references shouldn’t be there. I don’t know who was supposed to have reviewed it - maybe Linda [Mearns of NCAR] will know, as she used to or still does have something to do with BAMS. The inference in the email (from whence it came) is that it has been accepted !

Cheers

Phil

Our paper was not cited by the IPCC.

Comments welcomed and encouraged!

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1. Every U.S. president since Gerald Ford has had a year with no hurricane landfalls (President Obama holds the record) — 2025 is the first under President Trump.

2. Ryan hosts by far the best weather Substack — if you are not subscribed, you should be.

3. Unless otherwise indicated, data in this post comes from Phil Klotzbach and his great team at Colorado State University

4. If you are not subscribed to Jessica’s Substack, you should be.

5. I’ll update to 2025 when the year is complete, but 2025 is running well below average to date globally.

6. Careful readers will note that Trenberth was a co-author of the response to Pielke et al. 2005, which was published in November, 2005, but had been accepted at the time of the Jones-Trenberth exchange. It is not too much of a stretch to think that this email exchange is what motivated the furious attempt to prevent the publication of our paper, as it was peer reviewed and should have been considered by the IPCC. Even so, it has been cited ~500 times outside the IPCC.