The science of flooding

Anthony has an interesting report about a new paper that finds that increased flooding is mostly due to increased exposure - in other words that we are building homes closer to rivers than before. Flooding is therefore yet another area in which an impact from the warming at the end of last century is yet to be demonstrated.

Is there any justification for the kind of ambulance chasing exhibited by the Committee on Climate Change, for example this little gem from Lord Deben?

I hope floods will cause pause among dismissers. Can't forget "some woman Slingo" It revealed contempt they have for science.

If we recognise that the science is showing us that we cannot detect any influence of climate on flooding then I would posit that there is no justification at all. The contempt for science comes solely from the members of the committee and Professor Slingo who attempt to insinuate a link between what happened in Somerset and carbon dioxide, without any scientific evidence to support them,

The reality, as ever, is that there is only hypothesis and speculation.

Comments

[Martin A]

Well worth viewing.

Presentation of Prof. Murry Salby in Hamburg, Germany, on 18 April 2013 with the title: Relationship between Greenhouse Gases and Global Temperature

Note that Murry Salby is an atmospheric physicist with a heavyweight track record of research and publication over decades.

[SandyS]

For those interested Mike Jackson has created a discussion thread So where are Salby and Darwall wrong .... precisely?

I for one would be interested in reading the opposing views.

[Harry Passfield]

ATT-ME: "Then there's RealClimate and Skeptical Science - both excellent resources" Bwahahahahaha! (what did you expect?) William Connolley? ditto

[Martin A]

I for one would be interested in reading the opposing views.
Aug 20, 2014 at 7:13 PM | Unregistered CommenterSandyS

They are summarised in John Mashey's (Desmogblog*) Amazon review of Salby's textbook.

"Gets 1 for ~20 pages of anti-science nonsense, rest of the book likely would be a 4."

*"the world's number one source for accurate, fact based information regarding Global Warming misinformation campaigns."

[Mike Jackson]

SandyS
Thank you. I started that thread very specifically hoping that it would avoid this one becoming derailed.
I'm delighted to say that anders has replied and I hope others will join us over there and leave this thread to the important (very important, to my mind) subject of attributing floods.

Incidentally, I don't know whether Prescott gave the go-ahead for building on flood plains but I'm sure it was he who said, "The green belt is a Labour achievement; and we intend to build upon it". Lovely man. Political satire is the poorer without him.

[Philip Foster]

Here is a wonderful sample of Dame Slingo's 'understanding' of science:
"...these [climate] models are one of the great achievements of modern science."

I rest my case.
(H/T to Alex Henney)

[Bishop Hill]

Thanks to Mike for starting the dedicated Salby thread. Any further posts on that subject on this thread will be deleted.

[SandyS]

The environment Agency have a number of maps here http://maps.environment-agency.gov.uk/wiyby/wiybyController?topic=floodmap&layerGroups=default&lang=_e&ep=map&scale=1&x=357682.99999999994&y=355133.99999999994 where you can check out the risks. I put in the post codes for my home and work both of which survived (work only just) some floods at the beginning of the 21st century which were the worst in at least 50 years and since 1947 some say. The Environment Agency has both as

the area that could be affected by flooding, either from rivers or the sea, if there were no flood defences. This area could be flooded:
from the sea by a flood that has a 0.5 per cent (1 in 200) or greater chance of happening each year;
or from a river by a flood that has a 1 per cent (1 in 100) or greater chance of happening each year.

Which is about right or slightly pessimistic. Additional building and lack of maintenance increases the risk. There has been additional building of homes and industrial estates and warehousing. After a couple of years work after the floods maintenance has dropped off to pre-flood levels. Perhaps this is another example of where money spent on renewables would have better returns and create more jobs in preparing for the 1 in 25, 1 in 50 and 1 in 100 year events.

[Alex Cull]

A little historical perspective on flooding in the UK:
http://www.thamesweb.co.uk/windsor/windsorhistory/floods1875.html

[Steve Jones]

As someone who has lived in Suffolk for many years I can confirm John Selwyn Gummer is every bit as odious as previous commenters have suggested. His batman has started posting here recently; I'm sure you can guess who it is.

[William Baird]

Ah, Dear John Gummer!!

What a man, what an MP!!!, What a Lord of rubbish!! He used to be my MP many years ago.

Seriously though, Selwyn is the king of self opinionated useful idiots. It does the status of and regard for Parliament no good to allow this man and Tim Yeo onto any 'climate change' committee (or any committee).

Dame Julia Slingo is just following the official line, which does nothing for her integrity, or that of the Met Office.

[mike fowle]

Alex Cull, very interesting link. Restores some perspective. Thank you.

[JamesG]

For anyone else who suggests that a civil engineer is less to be believed than a climate scientist about the floods they should be aware that most of the work done on finite element analysis and similar discrete numerical methods upon which these climate models are all based was done by civil engineers. Engineers of course would never rely on unvalidated models and would never call hindcasting any more than a necessary but insufficient test because lives actually depend on their decisions.

But as for who to is correct, it is just a plain fact that the flooding was caused by a meandering jetstream and that cannot be attributed to manmade warming (especially the non-existent warming of the last 17 years) as there is no physics or data to support such an assertion. Slingo of course is aware of this - or at least you'd hope so. though it wouldn't be the first time I've come across a climate scientist who doesn't know anything beyond his/her very own narrow field. I'd hope a meteorologist would actually know some meteorology though. Who to believe? Well I tend to believe the people who don't have a track record of telling obvious untruths. Faux-greens will continue to believe that big business and everything that emanates from it is intrinsically bad of course; not that they're going back to the horse and cart anytime soon I suspect.

On flood plains it does strike me that medieval towns were built on hills because the marshes were full of mosquitoes and prone to floods. However for better or worse we decided to drain the marshes, dredge, bank and dam the rivers. Councils having once decided to do that, you'd expect them to keep it up and not just leave everything to return to nature again. It would certainly have been smarter to build houses on stilts in a flood plain but that is quite typical of the short-term thinking that is endemic in Britain. When I returned to Thameside it was in the middle of the drought 18 months ago and the MO was declaring that more droughts were likely (so I knew a flood was imminent), but the Thames was still dangerously full. However it seems while the council seems to have an unlimited supply of money for road humps they obviously spend absolutely zero on building up the crumbling river banks. We now know of course that the MO had told councils to expect more droughts rather than floods which tells us everything we need to know about their predictive skills.

[John Shade]

This thread was briefly derailed shortly after my comment yesterday at 2:01 PM. In providing a relevant quote from an article by Rupert Darwall, I mentioned the name Salby and that seems to have triggered some kind of nervous disorder in one of our more highly-strung readers. A side effect of which seems to be a loss of decorum. The derailment came to an end by 8:00 PM, thanks in large part to Mike J starting a Discussion thread on the focus of the diversion, and to Sandy S drawing attention to it here at 7:13 PM.

Back to my quote, or rather the highly perceptive Rupert Darwall's quote, about the sloppy scientific reasoning displayed by the IPCC. I repeat ithere for convenience:

The IPCC and other leading scientific bodies also appear to follow a pre-scientific injunction: “Seek and ye shall find.” The formulations “consistent with” and “multiple lines of evidence” recur throughout IPCC reports. The IPCC’s fifth assessment report, published in 2013, retreated slightly from previous certainty on humans’ contributing the totality of increased CO2. Now, the IPCC expressed a “very high level of confidence,” based, it said, on several lines of evidence “consistent with” this claim. Consistency with a proposition is weak-form science—the moon orbiting the Earth is consistent with pre-Copernican astronomy, after all—and a feature of the pseudosciences that Popper had seen in early-twentieth-century Vienna. In addition to seeking confirmatory evidence, AGW’s upholders often adopt the scientific equivalent of Don’t Ask, Don’t Tell when it comes to gaps in scientific knowledge—in particular, those gaps that, if filled in, might conceivably falsify their position.

This sort of reasoning is also to be found in Met Office pronouncements, such as Dame Julia's on the Somerset floods. Richard Lindzen alluded to this sort of thing in September last year:

It is worth noting that none of the above point to alarm. Nevertheless, there has been a huge effort to implement mitigation policies. The presumed basis is essentially the precautionary principle. Despite the fact that there is no evidence for alarm, neither can it be rigorously rejected. The arguments for alarm are, moreover, frequently based on the misuse of scientific statements. For example, the IPCC iconic statement that there is 90% certainty that most of the warming of the past 50 years is due to man’s emissions. While one may legitimately question the subjective assignment of a probability to such a statement, the statement, itself, is again completely consistent with there being no problem. To say that most of a small change is due to man is hardly an argument for the likelihood of large changes.
Such misuse of language and logic bring to mind Orwell’s comment on the political implications of language: “It becomes ugly and inaccurate because our thoughts are foolish, but the slovenliness of our language makes it easier for us to have foolish thoughts.” As to political language, itself, Orwell notes that it “is designed to make lies sound truthful and murder respectable, and to give an appearance of solidity to pure wind.”

A key phrase for me is this one: 'the statement, itself, is again completely consistent with there being no problem.' (the 'problem' being the supposed threat of CO2). This remark deserves to be heard whenever the facile association of bad weather with CO2 is made along the lines of 'this is consistent with global warming' and 'a large body of evidence exists'. The bad weather causes us problems but it is also 'completely consistent with' our CO2 having a next to negligible effect.

Lindzen's article, like Darwall's, is well worth reading. It is refreshing to encounter deep thought when we are in the midst of so much fluff, spin, and self-serving speciousness.

[Joseph Sydney]

There is nothing improper in permitting some people to build houses on flood plains and for other people to live in them, at their own risk. Indeed, permission should not be required. 'Planning control' is but the censorship of human creativity.

Some very wealthy land owners, corporate and personal, would welcome - and might even lobby for - the further restriction of such permitted liberties. It would bring them a welcome boost to land prices and rents.

[Charlie]

Since about 700 AD , there has been extensive change to the landscape of the UK. Large areas of Britain below 10ft above sea level were marshes. The Fens, Isles of Grain, Sheppey, Thanet and Athelney were largely cut off in winter. Drainage started with the Church from the end of the Saxon period and and then increased in the early Middle ages and then again in the 17C with the introduction of Dutch Engineers. The next large changes to land use occur with the need to increase food production after WW1 and 2. If on looks at many 19C landscapes there are extensive water meadows.

Since the 1970s JCB excavators and tracked excavators have enable drainage ditches to be deepened. The length of excavator booms have increased from about 2.5m to 5m over 40 years which has enables ditches to be deepened and therefore increased run off. Since the 1970s , the EU have funded extensive mole drainage. Tractors have increased in power, become 4 wheeled drive, tyres have become larger in diameter and wider all which has meant steeper slopes and wetter ground can be ploughed which all combine to produce greater run off.

Since 1945, extensive road embankments have been built on flood plains which has reduced flood storage and sometimes produced funnelling effects.

I would suggest that the building of houses on flood is just one of the many changes to land use which has increased run off since the 1800s. If one looks at buildings built pre 1800 and certainly Medieval very few flood. Good examples are the churches in Romney, some which are Saxon: they are located on small mounds which do not flood.

In areas which do flood many properties used to be built on stone mounds. If one looks at flood plains in a relatively natural state, flood waters are rarely deeper than 2 ft. Houses in flood plains normally have several steps leading up to the ground floor which comprise stone which have been waterproofed with beeswax ; carpets are loose and furniture can be easily moved upstairs. Most modern houses lack any measures to mitigate against flooding.

It is very difficult to define the changes which have occurred to the land surface over the last 600-700 years which have increased run off let alone calculate the impact.

The reality is that the engineering and scientific skills of the EA have decline dramatically in the last 20 years. I doubt that many EA staff realised that if dredging was stopped, that flooding could occur in the Somerset Levels.

Overall there are less people with the ability to analyse run off and flooding and probably less inclination to do so. Blaming everything on climate change saves everyone a lot of effort.

I am beginning to wonder whether blaming many problems on climate change is a way avoiding difficult scientific and engineering problems.

[David]

This effect is blindingly obvious here on the Costa Blanca where I live. All the historic villages and towns are built perched sensibly on hills or at the very least, higher ground inland from the Valencian plain along the coast. When it rains here it rains buckets due to a meteorological phenomenon called the Gota Fria which produces extensive flooding on the plain.
Since the 60's there has been extensive built out from the historic centers down onto the plain (formerly occupied solely by orange groves or rice paddies) and along the coastal strip behind the beaches. These areas are regularly subject to flooding. At least the Spanish aversion to fitted carpets, the universal use of ceramic floor tiles and a warm climate means that flooded properties can be rapidly cleaned and dried out.