Saturday, September 07, 2013

Atlantic Hurricanes will increase with global warming. Why are we not concerned?

Following from this post on global hurricanes, relating them to sea surface temperatures and the Pacific Decadal Oscillation, I have been looking at the record of Atlantic hurricanes, taken from Ryan Maue's site.

I have made a composite of Maue's record of North Atlantic hurricane energy (ACE) and the Atlantic Multidecadal Oscillation, which reflects sea temperatures in the Atlantic.

Fig 1 - North Atlantic hurricane energy with AMO
It shows a reasonable correlation between Atlantic surface temperature variations and accumulated hurricane energy. The correlation is poor in 1975-6, with more hurricanes than would be expected from the AMO. Global sea surface temperatures were higher in this period. (See Fig 6 on this linked page). Thereafter the relationship is pretty good, with the exception of 2006-7 when hurricane activity was less, though the AMO did not decline. Global sea surface temperatures were in decline from 2005-8.

Throughout the record, there is a tendency for the AMO to lead the ACE by a few months.

This correlation should not come as a surprise, since higher sea temperatures are a factor in creation of tropical cyclones and hurricanes, along with low wind shear and high humidity.

Fig 2 - Global Sea Surface Temperatures since 1850

Since global sea surface temperatures have been rising consistently since 1850, we can expect hurricanes to increase along with them.

Hurricanes have a significant impact on the economy. Since economics is the sole yardstick that conservatives apply to human well-being, it is utterly and totally irrational for conservatives to try to ignore, deny, suppress or minimise concern about global warming.

On the other hand, since the only concern of fossil fuel corporations is for their profit margin over the next four years, it is perfectly reasonable and consistent for them to persuade George Osborne and the media to try to ignore, deny, suppress or minimise concern about global warming.

I hope this helps.

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