The frequency of “extreme hydrological events” actually declined during the 20th century, despite global warming.
Monty Python’s four Yorkshiremen, who bragged of spending their childhoods in septic tanks or at the bottom of a lake, would be delighted to discover that floods really were worse when they were lads.
Since the 1950s both the number of lives and the amount of money lost to floods have declined markedly despite little change to the frequency of catastrophic floods, according to the first comprehensive study of European historical records
Academics at Delft University of Technology in the Netherlands found that the number of flood deaths across Europe has been falling by about 5 per cent a year for the last six decades. Financial losses to flooding have declined by roughly 2 per cent a year, according to their paper published in the journal Nature Communications.
Dominik Paprotny, who led the study, said that this was probably because people had migrated out of the countryside and into cities, which tend to be better protected, while houses now tend to be more soundly built and flood defences are stronger. The internal combustion engine and the invention of the helicopter have also made evacuating people from flooded areas a much easier prospect than it was in the Victorian era, he added.
Working from more than 300 sources including old books and newspaper clippings, the team created a list of 1,564 “damaging” floods that occurred between 1870 and 2016.
The number of bad floods per year did increase from around three in the late 19th century to more than 20 in the early 21st. However, records are heavily skewed as most of the middling-sized floods that happened before 1950 have simply passed out of memory.
When the academics tweaked the data to take this into account, they found that the upward trend vanished: if anything, the frequency of “extreme hydrological events” actually went down during the 20th century, despite global warming. Mr Paprotny said that climate change had actually reduced some flood risk factors, such as sudden thaws.
via The Global Warming Policy Forum (GWPF)
May 29, 2018 at 04:09PM