By Paul Homewood
The fraudsters are at it again:
It’s the latest extreme rain event supercharged by climate change that follows a summer of historic deluges in the Northern Hemisphere.
In just 12 hours, 29.2 inches of rain fell in Rossiglione in Italy’s Genoa province, roughly 65 miles south-southwest of Milan and 10 miles north of the Mediterranean coastline. It marked the greatest 12-hour rainfall on record in Europe, according to Maximiliano Herrera, a climatologist who specializes in world weather extremes.
The amount of rain that came down in 12 hours is more than half the typical amount of rain that falls in the region over an entire year, which is just over 50 inches. It’s several times the average October rainfall of 6 to 7 inches.
On the face of it, this appears to be an unbelievable amount of rainfall, just what the Washington Post want you to believe.
Fortunately though, there are local experts who know otherwise:
Very few weather stations anywhere in the world measured anything other than daily rainfall in the past. It is only recently that automatic gauges were introduced that could take hourly readings. Claims of a 12-hour record are therefore meaningless.
Furthermore many new sites have been added recently in mountainous locations, which inevitably tend to experience extreme rainfall. We have had exactly the same story here, with the Met Office regularly claiming “record rainfalls” at places like Honister Pass, high up in the Lake District, which was only opened up in the 1990s.
But even more significantly our Italian expert points to a much higher rainfall in 1970. So we now know that this month’s deluge was not unprecedented after all.
The Wikipedia article referred to translates as:
Note my highlight, that these sorts of rains are typical of Liguria, particularly in autumn.
There is a very good reason for this. The Ligurian coastline rises very quickly in altitude from the Mediterranean. Rossiglione for instance is just 10 miles from the coast, but is 1000 feet up. The mountains surrounding it are much higher still.
In autumn, the seas are still very warm, so any storm coming up from the south will draw in a lot of warm, moist air. As soon as it it hits Liguria, the air mass is forced thousands of feet upwards, rapidly dumping massive amounts of rain. The same topography ensures that these storms often get stuck in one place, unable to move further inland.
Once again then, the Washington Post has grossly misled its readers.
via NOT A LOT OF PEOPLE KNOW THAT
October 9, 2021