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By now you will have probably seen the reports about new research apparently showing that female named Atlantic Hurricanes are deadlier than male named storms because female names are ‘less scary’ than male names. The main investigation consisted of an analysis of 92 Hurricanes between 1950 and 2012 that made landfall in the USA (Katrina and Audrey, the two most deadly storms were excluded) examining fatalities, normalised damage, category, minimum pressure, gender of the storm name and year of occurrence.
There has been a fair amount of criticism on the paper from around the web including GRRLScientist in the Guardian, Future Tense in Slate, Not Exactly Rocket Science in National Geographic and on Mashable. The authors have responded to some of the criticism in these pieces.
The principal criticism has been on the approach to show that their finding is ‘significant’ which involves generalised linear regression on a negative binomial distribution and two-way interaction terms. Less fancy methods (simple correlation and a multi-linear regression) found no significant effect. B
Is there a difference in the number of people who die in Hurricanes based on the storm name’s gender?
You can’t just compare the average rates – Hurricane fatalities are a fat tail phenomenon, a small number of big storms contribute most of fatalities. Let’s forget modelling, regression algorithms and the fancier statistics. Let’s just look at the data. Below I’ve plotted the cumulative distributions of fatalities from male named storms and female named storms from the entire dataset.
You can see that for the high frequency, low fatality events the distributions are basically the same but there appears to be some divergence at the more severe end with a higher fatality rate in female named storms. But the difference isn’t that much – and there’s the data issue, with storms between 1953 and 1979 only receiving female names there’s way more of them than male named storms. So visually there’s not a huge difference and we can quantify this using a statistical measure called the Two-sample Kolmogorov-Smirnov test. This test allows comparisons of two samples of data and helps you decide between one of two hypotheses:
H0 – They’re from the same distribution.
H1 – They’re from different distributions.
For these data the KS-test gives D = 0.1065, p-value = 0.976. This means that we can’t reject H0 – i.e. we can’t tell if the two samples are different or there’s no detectable difference in the underlying pattern of fatalities based on storm name gender.
We can also look at only the storms during the time in which both male and female names were used:
Here we can see that what little difference we saw in the complete dataset disappears completely, further suggesting that the effect found by Jung et. al. is quite probably a statistical fluke. If you look at enough variables you’ll eventually find a statistically significant correlation. In fact if you look hard enough you can find all sorts of strange things that correlate with each other.
To explain the effect, the authors turn to additional experiments where they measured a difference based on storm name gender in perceived threat and willingness to evacuate. Implicit sexism plays a big, big role in our society. (I highly recommend Cordelia Fine’s book, Delusions of Gender, which goes into the detail very well) but it’s hardly the only thing at play – many factors cause people to (usually) downplay threats from and delay responses to Hurricanes and other disasters.
The scenarios presented (you can see examples here) were not anything like real Hurricane warnings and media broadcasts, which tend to be much more alarming and action oriented, especially for more severe Hurricanes which is where the authors claim there is an effect. A better experiment would be to mock up a TV news broadcast of Hurricane Alexander/Alexandria and show it to people in hurricane prone areas and see what the results are. I would be very surprised if there was still a detectable storm name effect once a heavy dose of reality is injected.
As for policy recommendations I think its definitely too soon to consider changing the naming system, but whilst we’re talking about communication the NHC could really overhaul it’s woeful public advisory messages.
Alternatively there’s always this idea:
I was going to write a post on the Bushfires in NSW, links to climate change and the media discussion after Adam Bandt’s comments (though I do wish to point out the irony that many of those criticising Bandt’s timing are more than happy to blame the fires on Green ideas about land clearing) but others have said it better than I. Here’s a wrap of some of the best coverage to date on the fires:
David Holmes in the Conversation looks at the media discussion of the bushfires and climate change. Despite calls not to ‘politicise’ research shows that now is the best time to talk about extreme weather and climate change. Also read Adam Bandt’s article that started it in The Guardian.
In the Guardian Josh Taylor outlines the benefits of social media in keeping tabs on what’s happening, but that it has its drawbacks too.
Although the fire season is likely to lengthen in the future detecting historical changes in seasonality is difficult as David Bowman examines in Crikey.
Also in The Conversation Ross Bradstock looks at the reasons why the Blue Mountains is so vulnerable to bushfires and Janet Stanley covers climate change, arson and land use as three areas that need a greater focus on prevention.
The Australian argues that despite losses and the early arrival of the bushfire season we are getting better at Bushfire Management. Technology is improving how fires are fought as detailed in the Daily Telegraph but models are far from reliable, as pointed out by David Bowman in the Conversation.
Well it’s a smokey morning in Sydney, thousands of firefighters are still working hard and about a hundred fires are still burning with many out of control. I’ve been following the news here in Italy.
If indeed hundreds of homes have been lost, this could very well be the most damaging fires in the state’s history and I would expect there to be strong pressure for the Government to establish some sort of inquiry. So I’ve pulled together some information on past fires in NSW and some of the inquiries that they triggered. The data is taken from the COAG Bushfire Inquiry, a few RFS publications, the Insurance Council’s disaster statistics and my own lists of disaster inquiries.
In terms of property loss and insured loss the worst bushfire disaster in the State’s history was the 1993-94 fires that destroyed 206 homes. These fires killed four people and led to three separate inquiries. Since then there have been ten separate audits, inquiries and reviews into bushfires in NSW. There’s also been numerous federal inquiries and in other jurisdictions which have driven policy change in NSW. The most deadly bushfire in NSW’s history was the 1968-69 fires which killed 14 people and also destroyed 161 homes. I hope all the lessons we’ve learned through these fires and inquiries will not lead to a toll that high.
And the Australian fire season still has a long way to go. Click here to look at the full table as a google spreadsheet.
Other Bushfire related inquiries
1996 – Audit of New South Wales Fire Brigades : fire prevention
1998 – Audit of The Coordination of Bushfire Fighting Activities
2000 – Parliamentary Inquiry into the NSW Rural Fire Service
2001 – Follow up of Performance Audits: Coordination of bushfire fighting activities
2003 – Coronial Inquiry into the Circumstances of the Fire(s) in the Brindabella Range in January 2003
2004 – Parliamentary Inquiry into Fire Services Funding
2005 – Statutory Review of the Rural Fires Act 1997
2009 – Review of Bushfire Arson Laws
Over 150 submissions have been received for the Recent trends in and preparedness for extreme weather events and they’re still coming. No doubt the recent bushfires and floods have intensified interest in the inquiry. I have doubts that the inquiry will be able to report by its current deadline of 20 March. Likewise I suspect that more hearings might be added to the three that have been currently announced.
As the first submissions come in and dates for public hearings are set I continue my series on the extreme weather and emergency preparedness senate inquiry. See Part 1, Part 2 and Part 3. In this post I move onto the fourth term of reference:
(d) an assessment of the preparedness and the adequacy of resources in the emergency services sector to prevent and respond to extreme weather events;
In the previous two posts I have examined current trends and future projections of climate change impacts on natural hazards, the estimated costs of extreme weather and potential insurance impacts. In this instalment I move onto the preparedness terms of reference:
(c) an assessment of the preparedness of key sectors for extreme weather events, including major infrastructure (electricity, water, transport, telecommunications), health, construction and property, and agriculture and forestry;