Archives par mot-clé : Floods

Australia, climate and geology

An Inconvenient Tree: Is Climate Change Driving Worse Floods

by E. Worrall, Nov 27, 2022 in WUWT

Does evidence of past extreme floods invalidate claims that climate change is making floods worse?

…

…

 

Could volcanic activity be a contributor to major floods in Australia? Australia is on the South Western edge of the Ring of Fire. While the Australian mainland is not very volcanically active, there have been some spectacular eruptions in our neighbourhood, such as the infamous Krakatoa eruption in 1883, or the 1815 Tambora Eruption, which is blamed for causing famine in the United States in 1816, “The Year Without a Summer”.

A notable volcanic eruption occurred at the start of 2022 – The Hunga Tonga eruption. JoNova published an intriguing comparison between the volcanic ash distribution from the Hunga Tonga eruption in January 2022, and 2022 rainfall anomalies across Australia. Hunga Tonga was light on sulphates, but the blast threw unprecedented amounts of water into the stratosphere. Where I live, on the Southern edge of the volcanic debris distribution, we’ve had some spectacular sunsets over the last year.

The apparent overlap between rainfall anomalies and volcanic debris could be a coincidence – but the comparison is visually intriguing.

…

unclassified

Biden falsely links Kentucky floods to ‘climate change’ – Reality Check: Floods ‘have not increased in frequency or intensity’ – White House ignores peer-reviewed studies & IPCC & data

by M. Morano, Aug 11, 2022 in WUWT

Study in the Journal of Hydrology finds no increase in floods – ‘Compelling evidence for increased flooding at a global’ scale is lacking’

Extreme Weather expert Dr. Roger Pielke Jr. comments on new study: ‘New empirical study: Are floods increasing in North America and Europe? No (and consistent with IPCC.)’

Study published in the Journal of Hydrology, Volume 552, September 2017, Pages 704-717. The study found:

‘The number of significant trends was about the number expected due to chance alone.’

‘Changes in the frequency of major floods are dominated by multidecadal variability.’

‘The Intergovernmental Panel on Climate Change (IPCC) concluded (Hartmann et al., 2013) that globally there is no clear and widespread evidence of changes in flood magnitude or frequency in observed flood records.’

‘The results of this study, for North America and Europe, provide a firmer foundation and support the conclusion of the IPCC (Hartmann et al., 2013) that compelling evidence for increased flooding at a global scale is lacking.’

…

climate-debate

New Study: 100-Year Flood Events Have Decreased Globally Since 1970

by  K. Richard, Apr 6, 2021 in ClimateChangeDispatch

In contrast to alarming claims about rare, 100-year flood events now occurring every few years due to global warming, scientists have determined the exact opposite is more likely true.

Not only have flood frequencies declined globally in the last 50 years, but the probability of a 100-year flood event is now so rare it has only been occurring once every 358 years on average since 1970.

According to the IPCC, there has been no clear evidence of a global-scale increase in flood magnitude or frequency in the last century (Hodgkins et al., 2017).

A new study (Slater et al., 2021) suggests that claims of flood magnitude, frequency, and probability dramatically increasing with global warming can be “misleading” if they use a stationary calculation approach instead of continually updating significant changes over time.

These scientists, using “observed annual maximum daily streamflow” records and a “nonstationary approach,” concluded there has been no obvious global-scale trend in 20-, 50-, and 100-year flood magnitude since 1970, with 100-year flood events defined as “flows of a given exceedance probability in each year.”

…

better to know...?, climate-debate

UK State Of The Climate Report 2019

by P. Homewood, April 16, 2020 In NotaLotofPeopleKnowThat

London, 16 April: The floods that affected northern England in the autumn of 2019 were nothing out of the ordinary. That’s according to a new review of the UK’s 2019 weather.

Author Paul Homewood says that although rainfall in the region was high, it has been exceeded several times in the past, right back to the 19th century.

…

Key findings

* After a rising trend between the 1980s and early 2000s, temperature trends have stabilised in the UK.

* Heatwaves are not becoming more intense, but extremely cold weather has become much less common.

* There is little in the way of long-term trends in rainfall in England and Wales.

* Sea-level rise around British coasts is not accelerating.

The UK’s Weather in 2019: More of the same, again (PDF)

better to know...?, climate-debate

Forget Climate Excuses: Environment Agency Ignored Flood Warnings For Years–The Times

by P. Homewood, Nov. 21, 2019 in NotaLotofPeopleKnowThat

As flooding spread across the country yesterday, the Association of Drainage Authorities said that warnings had been issued each year since 2007 at its annual conference, attended by Environment Agency staff.

The warnings were made by the association’s members in South Yorkshire, including John Duckitt, a farmer and elected commissioner of the drainage board that covers Fishlake near Doncaster, where parts of the village are still submerged more than a week after flooding began.

Speaking from his home yards from the Don, Mr Duckitt, 83, said that his concerns fell on “deaf ears”. He claimed that the agency “chooses to do as little as possible” and had allowed trees and plants to grow on the side of the river narrowing the channel after “ignoring local knowledge”.

“They knew about the problem and chose to ignore it,” he said. “This made the floods worse. Fair enough this flood was unprecedented but the Environment Agency, through lack of maintenance on the river, protracted the flood. It didn’t get away fast enough and did more damage.”

better to know...?, climate-debate

Kerala Floods “Likely Due To Climate Variability, Not AGW”–New Study

by P. Homewood, January 5, 2019 in NotaLotofPeopleKnowThat

…

Since there is no increase in mean and extreme precipitation in Kerala over the last six decades, the extreme event during August 2018 is likely to be driven by anomalous atmospheric conditions due to climate variability rather anthropogenic climate warming. The severity of the Kerala flood of 2018 and the damage caused might be affected by several factors including land use/ land cover change, antecedent hydrologic conditions, reservoir storage and operations, encroachment of flood plains, and other natural factors. The impacts of key drivers (anthropogenic and natural) on flood severity need to be established to improve our understanding of floods and associated damage.

http://www.geosocindia.org/index.php/jgsi/article/view/137443