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Re: [Phys-L] in the news: energy versus temperature



I checked the trend of available data on Cat 5 Hurricanes from 1924 on and counting year 2000+ as year 100+  on the  graph beneath for convenience, I see a slight decline in frequency there too.
Brian W
http://i880.photobucket.com/albums/ac6/betwys/hurriFreq.jpg

On 8/31/2017 4:15 PM, David Marx via Phys-l wrote:
Overall, the data shows a decline in both hurricane strength and activity as
well as a slight decline in strong tornadoes (cat 3 and above) over the last
few decades. In fact, the US went a decade without a hurricane above cat 1
making landfall. Harvey was a cat 4. The last cat 4 was Charley that struck
Florida in 2004.

https://en.wikipedia.org/wiki/List_of_United_States_hurricanes

https://www.ncdc.noaa.gov/climate-information/extreme-events/us-tornado-climatology/trends



On Thu, August 31,
2017https://www.ncdc.noaa.gov/climate-information/extreme-events/us-tornado-climatology/trends
7:51 am, John Denker via Phys-l wrote:
Hi Folks --


Here's a lesson about the difference between energy and
temperature, and about why you should care.

The surface temperature of the Gulf of Mexico last week
was warm, but not warm enough to explain, by itself, the strength of Hurricane
Harvey.


It turns out the interesting question is energy, not surface
temperature.

Back in the olden days, the Gulf would have a *thin* layer
of warm water at the surface. This would feed storms, but as soon as the storm
got going it would stir things up, mixing in cooler water from below, and the
storm would effectively blow itself out.

Nowadays, however, the warmth extends much deeper into
the water column. So the storm can persist much longer.

Back in the olden days, the storm surge from a powerful
storm could wipe out a coastal city in a couple of hours. Conventional wisdom
was that the storm surge was the thing to worry about. So people built
barriers to keep it out.

That wasn't what happened with Harvey. The storm surge
wasn't what got Houston. The problem was fresh water, not salt water, and it
arrived over the course of days, not hours. Coastal barriers don't do any
good when you get 50 inches of rain falling on the supposedly-protected side of
the barriers.

All this was completely foreseeable, and indeed foreseen.
Houston was warned, again and again, year after year, that
they needed to do more in terms of flood abatement, but they did virtually
nothing. Not even a building code to discourage people from building in
low-lying areas. Also they persisted in using out-of-date planning maps. One
neighborhood in Houston is /outside/ the 500-year floodplain, according to
the "official" maps, yet has flooded three times in the last ten years. Prof.
Poisson tells me the chance of
that happening randomly is about one in a million.

I wonder how many 200-billion-dollar losses people have to
sustain before they start taking climate change seriously. As the saying goes,
$200 billion here, $200 billion there,
and pretty soon it adds up to real money.

More generally, the subsidies for the fossil-fuel industry
are on the order of trillions of dollars per year:
https://www.theguardian.com/environment/climate-consensus-97-per-cent/2017/au
g/07/fossil-fuel-subsidies-are-a-staggering-5-tn-per-year
http://www.sciencedirect.com/science/article/pii/S0305750X16304867
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