Note: This post is co-authored with Ryan Maue, an absolutely top-notch atmospheric scientist and data wrangler. Give him a follow on Twitter: @RyanMaue and check out his tropical activity tracking page.
Back in 2012, Jessica Weinkle (@Jessica Weinkle), Ryan Maue (@RyanMaue) and I published in the Journal of Climate the first peer-reviewed paper with a comprehensive dataset of global tropical cyclone landfalls.
In 2019 we shared an updated version of the data at the request of the World Meteorological Organization (WMO) as part of their assessment of tropical cyclones and climate change. That WMO assessment was heavily relied on by the most recent assessment of the Intergovernmental Panel on Climate Change. [emphasis, links added]
Today we share the most recent update, with data on global hurricane landfalls from 1970 to 2022 at the global level, and going back further in time for several of the most active locations for tropical cyclone activity. You won’t find this data anywhere else.
In our 2012 paper, we discussed the detection of long-term trends in landfall:
“We have identified considerable interannual variability in the frequency of global hurricane landfalls; but within the resolution of the available data, our evidence does not support the presence of significant long-period global or individual basin linear trends for minor, major, or total hurricanes within the period(s) covered by the available quality data.”
The figure below provides the latest update to Figure 2 of the original paper.
In 2022 there were 18 total landfalling tropical cyclones of at least hurricane strength around the world, of which five were major hurricanes.
Since 1970 the median values are 16 total hurricanes, with 5 of major hurricane strength. So 2022 was very close to the median of the past half-century.
Overall, based on IBTrACS best-track and preliminary data from Colorado State University since 1980, the overall number of hurricanes globally in 2022 was 86 (median = 87) and major hurricanes were 17 (median = 24).
The figure below shows no long-term trends in hurricanes or major hurricanes.
If we look closely at the 12-month sums shown in the figure above, we also see that the most recent 24 months have close to the least overall global activity of the past 40+ years, for both hurricanes and major hurricanes.
This is not unexpected due to the ongoing triple-dip La Niña that tends to depress Pacific tropical cyclone activity while the Atlantic typically sees more frequent and intense hurricanes.
Our data also allow us to provide estimates of global landfalls going back further in time to 1950. The figure below sums:
- (a) observations from 1950 from the Western North Pacific (WPAC, where aircraft reconnaissance of tropical cyclones has taken place since 1944) and North Atlantic, together representing >70% of global hurricane landfills, and
- (b) an estimate of the landfalls from the rest of the world from 1950 to 1969 based on their statistics from 1970 to 2022.
The most striking feature of this figure is the pronounced dip in global landfalls in the 1970s and 1980s. If we look at just the landfalls in the WPAC and North Atlantic since 1945, there has been an overall sharp decline.
We have often urged caution in over-interpreting tropical cyclone time series that begin in the 1970s and 1980s because it is well understood that this period represented a low point in activity.
Starting an analysis in that period invariably results in upward trends in tropical cyclone activity. But start the same analysis in the decades before, and those trends are muted or disappear altogether.
The most active tropical cyclone basins around the world are modulated by El Niño and La Niña on interannual time scales, but also interdecadal ocean oscillations like the Pacific Decadal Oscillation and Atlantic multidecadal variability.
The Atlantic basin has generally been active since 1995, and how long this might last is uncertain.
If we look at the “accumulated cyclone energy” (ACE, an integrated value of frequency and intensity) of all global tropical cyclones of at least tropical storm strength from the CSU dataset, we see no overall trend since 1980, as you can see in the figure below.
Importantly, when we look at global ACE per hurricane, we also see no trend, as you can see in the figure below.
This means that hurricanes to date have not generally become more intense, although they may be later this century.
However, as oceans warm, if all else is equal, the maximum potential intensity of hurricanes would increase, and as a result, they will have greater precipitation.
To date, observational evidence in support of theoretical expectations based on landfalling storms is mixed (see, e.g., here, here, here, here, here).
That we don’t presently see strong trends in tropical cyclones is not at all surprising. Research indicates that if climate models are accurate in their projections, we would not expect to be able to detect such trends for many decades or longer.
One big reason for this is tropical cyclones have a lot of variability in interannual and interdecadal time scales and projected changes in storm behavior are relatively much smaller.
A common error in media coverage of hurricanes is to suggest that small trends possibly detectable later this century can be observed in the behavior of individual storms today.
In sum, over the past 70-plus years, landfalling hurricanes and major hurricanes have seen considerable multi-decadal and interannual variability, but there have not been pronounced trends.
This is consistent with the current scientific consensus as reported in many IPCC and WMO reports.
For the North Atlantic (where the U.S. east and Gulf coasts are located), the National Oceanic and Atmospheric Administration have recently concluded:
“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.”
At the global scale, the most recent IPCC assessment concluded:
“There is low confidence in most reported long-term (multi-decadal to centennial) trends in tropical cyclone frequency- or intensity-based metrics.”
If you’d like to explore the dataset from our 2012 paper yourself, it can be downloaded here.
Read more at The Honest Broker
This leaves out Gore, DiCaprio, Redford and David(Laurie)out of t he whole thing. As Joe Friday would say JUST THE FACTS MAM
Atlantic hurricanes have most definitely increased in intensity and decreased in the time it takes to get that strong.
Landfall events did not increase but the the ones that landed tended to be stronger on average.
Landfall events don’t really indicate anything other than the hurricanes hit land. I guess that is why this article on this joke of a publication tries to push that as its main point.