NOT A LOT OF PEOPLE KNOW THAT

By Paul Homewood

Melissa is now ranked tie 3rd most intense Atlantic hurricane at 892mb. We can look at it in graph format:

The picture is stark – nearly all of the eleven most intense have occurred in recent years, including the two most intense, Gilbert in 1988 and Wilma in 2005. Does this mean then that global warming really is making hurricanes more intense?

WHOA THERE!!!

Take another look at that table.

Of the eleven on the list, seven were logged out at sea. Of the other four, we already know that the Melissa reading was not at landfall but occurred several hours before at sea.

Dean’s minimum pressure was measured at landfall but was observed by hurricane hunters. The other two, Labor Day and Camille, were the only two genuinely recorded at the surface on land.

When we separate readings at landfall and at sea, we get a different story:

It is not a coincidence that mid ocean hurricanes did not feature before 1980, because proper technology did not exist then to measure them, whether satellites or aircraft.

We know that hurricanes almost invariably weaken as they approach land, so comparing mid-ocean intensities with landfall ones is a meaningless exercise.

But it gets worse.

On the Wikipedia table of most intense hurricanes at landfall, all of the modern entries were taken by hurricane hunters – Dean, Dorian and Irma.

Nowadays hurricane hunters are able to stay inside hurricanes for hours on end, able to seek out the highest wind speeds and lowest pressures. In contrast, measuring hurricanes like Camille relied on land based thermometers, which were extremely unlikely to be at the exact spot where pressure was lowest.

Scientists at the US Hurricane Research Division have done sterling work with their attempts to reanalyse past hurricanes. But as good scientists, they have to be conservative in their findings. They only estimate pressures and windspeeds that they can sensibly justify. Believing that a hurricane was probably more intense is not enough if you don’t have the data to back it up.

Many hurricanes only hit small islands – Dorian and Irma for example. Hurricane hunters are invaluable in getting measurements in these situations where previously there may have been no reliable land-based data.

Hundreds of catastrophic hurricanes have hit the Caribbean over the years. Just because we don’t have accurate data on them does not make them less catastrophic.