Ten years after Katrina: let’s learn from those predictions of more & bigger hurricanes

Summary — Most 10-year anniversary articles about Katrina omit one chapter of that sad story: its exploitation by climate activists. They predicted more and stronger hurricanes. Let’s grade them. Every time activists falsely cry “wolf” we become weaker, less able to prepare for real threats. Remembering is the first step to learning.

“Sooner or later, everyone sits down to a banquet of consequences.”
— Attributed to Robert Louis Stevenson.

Eye of the hurricane


  1. Katrina and Wilma hit America.
  2. Alarmists exploit the disaster.
  3. Hurricanes go MIA.
  4. Forecasts of  hurricanes.
  5. Conclusions.
  6. For More Information.
  7. A book recommendation.

(1) Katrina and Wilma hit America

The 2005 hurricane season was the most active on record by many measures. Ten years ago today Hurricane Katrina almost destroyed New Orleans (details here). Hurricane Wilma hit in Florida on 24 October 2005 (among the most powerful ever recorded in the Atlantic basin).

(2)  Alarmists exploit the catastrophe

Climate alarmists exploited this disaster. For example see Al Gore’s speech at Sierra Club’s National Environmental Convention and Expo in San Francisco on 9 September 2005 — excerpt…

“Winston Churchill, when the storm was gathering on continental Europe, provided warnings of what was at stake. And he said this about the government then in power in England — which wasn’t sure that the threat was real — he said, “They go on in strange paradox, decided only to be undecided, resolved to be irresolute, adamant for drift, solid for fluidity, all powerful to be impotent.” He continued, “The era of procrastination, of half measures, of soothing and baffling expedience of delays, is coming to a close. In its place we are entering a period of consequences.”

“Ladies and gentlemen, the warnings about global warming have been extremely clear for a long time. We are facing a global climate crisis. It is deepening. We are entering a period of consequences.

“… Last year we had a lot of hurricanes. Last year, Japan set an all-time record for typhoons: 10. The previous record was 7. Last year the science textbooks had to be rewritten. They said, “It’s impossible to have a hurricane in the South Atlantic.” We had the first one last year, in Brazil. We had an all-time record last year for tornadoes in the United States: 1,717. Largely because hurricanes spawned tornadoes. Last year we had record temperatures in many cities. This year 200 cities in the Western United States broke all-time records. Reno: 39 days consecutively above 100°.

“The scientists are telling us that what the science tells them is that this — unless we act quickly and dramatically … {t}his, in Churchill’s phrase, is only the first sip of a bitter cup which will be proffered to us year by year until there is a supreme recovery of moral health.”

Since Katrina, climate activists have beat a steady drumbeat warning of doom.

  1. Warming seas cause stronger hurricanes“, Nature, 2006 — “Mega-storms are set to increase as the climate hots up.”
  2. Are Category 6 Hurricanes Coming Soon?“, Scientific American, 2011 — “Tropical cyclones like Irene are predicted to be more powerful this year, thanks to natural conditions”
  3. Global warming is ‘causing more hurricanes’“, The Independent, 2012.
  4. A Katrina hurricane will strike every two years“, ScienceNordic, 2013 — About a widely reported study in PNAS by geophysicist Aslak Grinsted of the Niels Bohr Institute Copenhagen U. Also see “‘Katrina-Like’ Hurricanes to Occur More Frequently Due to Warming” in US News & World Reports.
  5. Hurricanes Likely to Get Stronger & More Frequent“, Climate Central, 2013 – About a study in PNAS by Kerry Emanuel et al.
  6. See ten even more outlandish predictions from the big 3 networks.

We should distinguish between the research of scientists, unbalanced reporting of research by journalists, and exaggeration of their findings by activists. Science advances by bold predictions, valuable no matter what the result. Of course, studies are news. But journalists often do not state the long-term scope of these forecasts, hide the uncertainty, and show only one side of the debate among scientists. There were balanced articles after Katrina, but too few to counterbalance the alarmists.

  1. Can we expect more hurricanes like Katrina?“, The Guardian, 2005.
  2. Debunking the Myths of Hurricane Katrina“, Popular Mechanics, 2006 — Debunked myths, but most remain widely believed.
  3. Climate myths: Hurricane Katrina was caused by global warming“, New Scientist, 2007.
  4. Hurricanes and global warming: 5 years post Katrina“, Judith Curry (Prof Atmospheric Science, GA Inst Tech), 2010.

(3)  Hurricanes go MIA

Among the longest records of active hurricane zones is on the US east coast. NOAA’s Hurricane Research Division has data back to 1851. No major hurricane (category 3 or more) has hit the continental US since Wilma in October 2005. That is the longest pause on record. NOAA says “It is premature to conclude that human activities — and particularly greenhouse gas emissions that cause global warming — have already had a detectable impact on Atlantic hurricane activity.

Despite the confident forecasts of doom, global hurricane numbers and energy show no trends (scroll down to see the graphs here); reliable records begin in 1970. Here are two papers crunching the numbers. Red emphasis added.

(a)  Excerpt from “Comments on “Monitoring and Understanding Trends in Extreme Storms: State of Knowledge” by Christopher William Landsea in the Bulletin of the American Meteorological Society, July 2015. No significant trend in the number of US hurricanes hitting the US since 1900; the increase since 1970 appears to be natural variation.

Atlantic hurricane landfalls on America

“Figure 1 provides an analysis of U.S. hurricanes from 1900 through 2014. The record begins at the start of the twentieth century as it was approximately at that time that enough coastal communities were established along the U.S. Gulf of Mexico and Atlantic Ocean coasts to ensure a relatively complete monitoring of all U.S. hurricanes …

“The figure shows that there has been a small, statistically insignificant downward trend in the frequency of U.S. hurricanes in this century-long time series. Instead, the record is dominated by interannual- to decadal-scale variability, with the busiest periods occurring in the 1910s, the 1930s to the 1950s, the mid-1980s, and the mid-2000s, while the quietest periods are seen during the 1920s, the 1970s to the early 1980s, the early 1990s, around 2000, and the last few years.

This U.S. hurricane record then puts the results of Kunkel et al. (2013) for Atlantic basinwide activity showing a sizeable increase in activity since 1970 into perspective. The long U.S. landfall record is an indication that this recent upward phase of activity in the Atlantic basin was preceded by quiet and active periods of similar magnitude.

(b) Validating Atmospheric Reanalysis Data Using Tropical Cyclones as Thermometers“, James P. Kossin, Bulletin of the American Meteorological Society, July 2015 — Excerpt…

“The question of how tropical climate variability and change has affected and will affect tropical cyclones has been the subject of intensive study. Theory and numerical modeling simulations suggest that increases in the mean potential intensity of the environment through which tropical cyclones track will cause mean tropical cyclone intensity to increase.

“… Time series of the annual-mean storm-local potential intensity calculated from the MERRA, ERA-Interim, and NCEP/NCAR data … the NCEP/NCAR data exhibit a statistically significant increasing trend, but no trends are found in the MERRA or ERA-Interim data. … This has important implications because a lack of storm-local potential intensity trend implies that there is no manifest expectation within the constructs of potential intensity theory that mean tropical cyclone intensity has increased over the past 30 years.”

(4)  Forecasts of increasing hurricane intensity

Here’s one of the most-cited predictions of increased tropical cyclone activity: “Downscaling CMIP5 climate models shows increased tropical cyclone activity over the 21st century” by Kerry A. Emanuel in PLOS, 23 July 2013 — This study uses RCP 8.5, the worst of the 4 scenarios in the IPCC’s AR5. Abstract…

“A recently developed technique for simulating large numbers of tropical cyclones in climate states described by global gridded data is applied to simulations of historical and future climate states simulated by six Coupled Model Intercomparison Project 5 (CMIP5) global climate models. Tropical cyclones downscaled from the climate of the period 1950 – 2005 are compared with those of the 21st century in simulations that stipulate that the radiative forcing from greenhouse gases increases by 8:5 W m−2 over preindustrial values.

“In contrast to storms that appear explicitly in most global models, the frequency of downscaled tropical cyclones increases during the 21st century in most locations. The intensity of such storms, as measured by their maximum wind speeds, also increases, in agreement with previous results. Increases in tropical cyclone activity are most prominent in the western North Pacific, but are evident in other regions except for the southwestern Pacific.

“The increased frequency of events is consistent with increases in a genesis potential index based on monthly mean global model output. These results are compared and contrasted with other inferences concerning the effect of global warming on tropical cyclones.”

Forecast of hurriances

The global number of tropical cyclone calculated using historical simulations for 1950–2005 and the RCP8.5 scenario for the period 2006–2100.

(5)  Conclusions

Will a strong hurricane hit America and wreck another major city? Certainly, eventually. Unfortunately, it seems likely that that city hit will be only slightly better prepared than were New Orleans and New York City (hit by tropical storm Sandy in 2012). Our preparations for most forms of extreme weather are no better.

Historians will more accurately assess the causes of our irresponsible public policy than we can, but a large role clearly results from the often disturbing behavior of climate scientists, unlike what the public expects from those warning of a global disaster, and the routine exaggerations and false predictions by activists. Perhaps historians will assign even more blame to our unwillingness to take responsibility for this serious issue: get clearer answer and act accordingly.

Truth Will Make You Free


“We don’t even plan for the past.”
— Steven Mosher (member of Berkeley Earth; bio here), a comment posted at Climate Etc.

(6)  For More Information

One thing that has changed: “Hurricane Forecasts Have Become Much, Much Better Since Katrina“. For more about the current debate in climate science about the see “Mixing Politics and Science in Testing the Hypothesis That Greenhouse Warming Is Causing a Global Increase in Hurricane Intensity” by Judith Curry et al, Bulletin of the Am Meteorological Society, August 2006.

To learn about the political failures that created the disaster see “The Slow Drowning of New Orleans” by Michael Grunwald & Susan B. Glasser, Washington Post, Oct 2005.

Please like us on Facebook, follow us on Twitter, and post your comments — because we value your participation. For more information about this vital issue see The keys to understanding climate change and My posts about climate change. Especially see these posts about climate forecasts…

  1. More about the forecast for flooded cities in the late 21st century.
  2. Looking into the past for guidance about warnings of future climate apocalypses.
  3. Checking up on past forecasts about climate change, a guide to the future.
  4. Will we see the end of snow? More importantly, when will we learn to see the world clearly?
  5. 5 years later: checking up on the 2-minute hate at George Will about melting of the polar ice — He was right; Gore was wrong. No trend for 10years.
  6. We must rely on forecasts by computer models. Are they reliable?
  7. Is our certain fate a coal-burning climate apocalypse? No!
  8. Six headlines from 2009 telling us important news about 2015’s climate — Deadlines to save the Earth.

To support the FM website project please hit the tip jar (on top of the right-side menu bar). Your help makes this possible.

(7)  To help you better understand today’s extreme weather

To learn more about the state of climate change see The Rightful Place of Science: Disasters and Climate Change by Roger Pielke Jr. (Prof of Environmental Studies at U of CO-Boulder, and Director of their Center for Science and Technology Policy Research).

The Rightful Place of Science: Disasters and Climate Change
Available at Amazon.

16 thoughts on “Ten years after Katrina: let’s learn from those predictions of more & bigger hurricanes

  1. For those interested in a broad brush overview I put a small article on hurricane formation and climate change on my website. It starts with:

    When “Andrew” made its hit on Florida in 1992 local residents and authorities received a rather rude wake-up call on how vulnerable they were. The city of Homestead was ravaged. …if residents of the Florida Keys would decide to “ride out the storm” like they did with “Georges” in 1998, they would face annihilation in the case of a repeat of the Labor Day Storm scenario. … The year 2005 provided a second wake-up call. The name was ‘Katrina’.

    Also the following questions are dealt with:

    • How much energy is transferred by Hurricanes?
    • Some notes on the Atlantic Multidecadal Oscillation
    • Some on links between warmer sea water and more intense hurricanes

    With respect to the latter: Except for the North Atlantic and Caribbean – a modest overall increase in strength and numbers(•) – there is up to now no trend in numbers and average intensity visible. A tempting question is “why?”, because one would expect an increase in intensity on thermodynamic grounds.

    Finally: Apart from the question when, and by how much, hurricanes could intensify, the list of “prime targets” along the US east and south coast is impressive: New York, Atlantic City, Ocean City, Charleston, Miami, Tampa, Pensacola, Mobile, Gulfport, New Orleans, Galveston … In case of an onslaught by a category IV-V hurricane, the question one could raise is: How well prepared are they?

    Mazzel & broge / kind regards, Evert Wesker

    (•) P.S.: Forget about the 2005 hurricane season in the North Atlantic and Caribbean; that was in my view a once in a lifetime event.

    Liked by 2 people

Leave a comment & share your thoughts...

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s