Are Hurricanes Getting Worse? (original) (raw)

That “climate change” — undefined and usually unquantified — is making weather patterns more adverse is a given among the chattering classes, but it always is useful to examine the actual underlying data. A prominent example appeared in a recent column in The Hill, in which reporter Rachel Frazin argues that “Climate change is making hurricanes like Hurricane Helene more intense, scientific research shows.” Frazin notes as well that:

• “The proportion of hurricanes that fall into these more intense categories 4 and 5 are expected to increase as the planet heats up, according to the most recent report from the Intergovernmental Panel on Climate Change…”
• “Peak hurricane wind speeds are also expected to rise.”

The data on hurricane frequencies and intensities do not support those assertions. Here are the satellite data beginning in the early 1970s on the global numbers of tropical storms, hurricanes, and major hurricanes. What is the basis for the adverse “expectations” on increasing frequencies for category 4 and 5 hurricanes?

Are peak hurricane wind speeds rising, as Frazin seems to believe? Here are the satellite data on accumulated cyclone energy, the standard wind speed index measuring the intensity of given cyclones and overall cyclone seasons. Again: What is the basis for the adverse “expectations” on increasing peak hurricane wind speeds?

As a reporter, Frazin should have compared these actual data with the worsening conditions “expected” by the scientists and “experts” quoted in her column. She should have asked how the data compare with the predictions posited by those experts in the past. The problem is that “expectations” are predictions, usually based upon climate models that have overstated the actual temperature record by a factor of about 2.3.

Experts and scientists, whatever their credentials, might “expect” many things, but a failure of the predictions actually to materialize usually imposes no professional penalty in the strange world of climate politics. After all, an adverse prediction about the future can always be pushed back to later years.

With respect to Frazin’s assertion that IPCC “expects” an increasing proportion of Category 4 and 5 hurricanes: Let us review what IPCC actually says in the latest 6th Assessment Report (section 11.7.1.4) about cyclones:

[T]here is still no consensus on the relative magnitude of human and natural influences on past changes in Atlantic hurricane activity, and particularly on which factor has dominated the observed increase (Ting et al., 2015) and it remains uncertain whether past changes in Atlantic [tropical cyclone] activity are outside the range of natural variability.

Translation: We cannot tell even if there has been an increase in Atlantic hurricane activity simply as a matter of statistical significance. And to the extent that there has been such an increase — the Ting et. al. paper is not up to date — there is no consensus on the relative contributions of natural and anthropogenic influences.

Reporters working in the climate science and policy area need to bear in mind that hurricane seasons bring with them hurricanes. Some of them will be major. But the attendant analytic and scientific complexities are staggering in terms of attempts to predict future storms, or to discern changes in underlying trends, or to attribute any trends to increasing atmospheric concentrations of greenhouse gases.

More generally, scientists often are not disinterested observers, and the common assertion that there exists some sort of “consensus” is both false and fundamentally anti-scientific in that “science” is a continuous process of discovery and challenge. Reporters accordingly should strive to seek out a range of informed opinion, and report areas of agreement and disagreement to their audiences. In so doing, reporters would return to their traditional role as providers of crucial information for an informed public.