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Dec102015
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Bishop Hill
Bishop Hill Me on the floods
Dec 10, 2015 Climate: WG2 ;)
I have a post up at the Spectator blog about the Cumbria floods.
Read it here.
Dec 10, 2015 Climate: WG2 
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Dec 10, 2015 Climate: WG2
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Reader Comments (83)
Dame ‘barbecue summer’ Slingo is the UK's Tim Flannery ...after his endless assertions that Australia's climate had changed to permanent drought. So then Oz spent $billions on desalination plants which they never use, cos the dry spate changed back so most of the country the rain is sufficient.
Then the US went crazy after Hurricane Katrina predicting a new era of hurricanes, but instead they got a fallow period. So that when that Hurricane Patricia came and was declared "Mexico awaits 'strongest ever' storm " ..not that much happened.
It wouldn’t surprise me if these UK floods are the same, that this is just the mathematics of randomness that sometimes flood years bunch up and likewise there are fallow patches. Just like in the 1930's dustbowl era (Which was was climate cycle, not overfarming)
As @Martin Brumby points out the "seven times more likely" Met office like is a result of a bit of statistical cherrypicking
The Met should have known their quote would be requoted erroneously as flood events are seven times more likely.
Now Slingo is quoted as
I'd like to hear some coverage of people who didn't just rely on EA's assertions that their area was flood safe, but rather took their own measure of putting in flood resistant doorways, proper drainage, weather monitoring etc. but pictures of a dry house doesn't make good telly.And as climate cycles there should be benefits in some areas whilst there are negatives in others. More floods oin one area might coincide with less hurricanes in another.
Bish, you say:
Over at Paul Homewood's blog on 8th December I said:Great minds and all that!
I see Phil laughing out loud in earlier comments. I suppose it's good that someone, somewhere is getting pleasure from what is happening in Cumbria and elsewhere.
I have relatives in Whitehaven and Egremont, including a cousin in the Coastguard.
They also find the bending over backwards, pretzel logic and half-truths on show hilarious.
HTH.
Really? It's not that hard. CO2 is a greenhouse gas (everyone here, I'm told, accepts this). It acts to reduce the outgoing longwavelength flux and - as a consequence - leads to an increase in temperature. Evaporation depends on temperature. The higher the temperature, the higher the evaporation rate (the molecules are more energtic). If the evaporation rate goes up, then one might expect that rate at which it precipitates to go up too. See, not that hard.
You're being ironic, right?
It's time for Slingo to leave.
Tom Spencer a reader in coastal ecology and geomorphology at the University of Cambridge, said some stuff…
This guy?
It is of concern that historical data suggests there is far more capacity in the North Atlantic climate system to produce wetter and more prolonged flood-rich periods than hitherto experienced in the 21st century. Looking forward, an increased likelihood of weather extremes due to climate change means that extending our flood record using geomorphology science must be placed at the centre of flood risk assessment in the UK.”
https://www.cam.ac.uk/research/news/unprecedented-storms-and-floods-are-more-common-than-we-think
This guy?
No, surely not? Maybe there's another reader in coastal ecology and geomorphology called Tom Spencer at the University of Cambridge?
@Retired Dave: a good article. I am currently updating Planck's work. The climate models are broken.
Safe from drought then - till the temperature drops.
Dec 11, 2015 at 8:17 AM ...and Then There's Physics,
Yes, I made similar arguments back when AGW was going to cause droughts in the UK and we were all urged to buy tropical plants for our gardens.
But apparently the science was settled differently then.
In those days, I hadn't realised that CO2 is fundamentally a magical molecule and will demonically cause whatever weather has just happened.
Does anybody have a reference for Dame Julia's "seven times more likely" claim as per stewgreen's link?
What does it mean? What was the base line probability, what event does it apply to, when did it apply, how was it calculated, was it validated by observation and how has this new seven times greater probability been calculated?
As pointed out earlier, especially clearly by Martin Brumby, a 1 in 100 year flood does not literally mean that, but it is read as such by the headline MSM reporters, who feed it to the general public and people such as Raff take it onboard.
There is an explanation of how these figures are arrived at here, together with more explanation of recurrence intervals:
http://water.usgs.gov/edu/100yearflood.html
"The term "100-year flood" is used in an attempt to simplify the definition of a flood that statistically has a 1-percent chance of occurring in any given year. Likewise, the term "100-year storm" is used to define a rainfall event that statistically has this same 1-percent chance of occurring. In other words, over the course of 1 million years, these events would be expected to occur 10,000 times. But, just because it rained 10 inches in one day last year doesn't mean it can't rain 10 inches in one day again this year."
More discussion here:
http://gallery.usgs.gov/audios/50#.VmqbzcRKV_A
Radio interview:
We want to talk today with Bob Holmes who is the National Flood Coordinator for the USGS.
...you know we hear this phrase "500 year flood." And supposedly this is the 2nd 500 year flood within fifteen years. Is that correct?
Bob: That's right, I mean, some of our numbers are showing that this, least on our frequency probability curves is about the second 500 year flood we've had in 15 years.
Scott: What exactly does that mean? How can you have two 500 year floods in 15 years?
Bob: Essentially, I think as hydrologists, we've done ourselves a disservice by calling it that. Essentially it's a probabilistic measure. A lot of people think "OK, if I've had a 500 year flood now, this year, we've got 499 years. We don't have to worry about it again." And that's simply not the case. Essentially, a 500 year flood is just that quantity of water that has the 1 in 500 chance in happening in any one year. Another way to say it would be, there's a .2% chance of a flood of this magnitude occurring in any one year. So, it's essentially a probabilistic measure. We take our annual peak flow values from the USGS gages and we fit a probability model to those and come up with a number for a 100 year, a 500 year a 25 year whatever.
Scott: So, I mean, will it ever go above 500 years? Is that even possible?
Bob: Well, Probabilistically yes sure, I mean you can have anything you want. But you have to remember this is the value of the long term gauging data. And this is why we really make every effort to keep gauges active for long periods of time because the more data you have... If we put a probability model to a gauging station with 25 years of record, that model is not as reliable as a gauging station with 150 years of record. Now, most of our gauges are well less than 100 years. Now In a current flooding area, we do have some gauges. Like on the Cedar Rapids, we've got a105 years of records there. So, those probability models are better than a gauge that's just been there for 20 or 30 years of records."
Honister QED?
ATTP
Is that why we get more floods in Summer when the temperatures are higher?
Roger,
A relatively quick google search would probably tell you that the UK is a country that typically gets more rain in the autumn and winter, than in the summer and spring. I shall leave it to you to ponder the significance of that.
The USGS site is quite fascinating and worth a wander through their links, eg this one on stream flow: http://water.usgs.gov/edu/watercyclestreamflow.html
"On Dec. 24, 2002, about two inches of rainfall fell in the Peachtree Creek watershed. ...the baseflow was about 50 ft3/s before the river started to rise, but that just a few hours later, at 9:00 AM streamflow was over 6, 000 ft3/s - that is about 150 times the amount of water flowing by as during baseflow conditions. This is characteristic of small streams, especially urban streams where runoff enters the river very quickly."
aTTP
Perhaps you should ponder the significance of irony...
John Brignell on Records
http://www.numberwatch.co.uk/record.htm
Sorry - I just saw on page1 that Martin Brumby has already provided a reference for Dame Julia's 7x claim. I'll follow up on that.
ATTP: I can't believe you are a physicist. You are clearly a fake or else you skipped the lectures covering thermodynamics, heat transfer and fluid flow. You will say anything to keep the climate change scam going.
Philip,
Well, I am. You can choose not to believe it if you wish.
Are you suggesting that you would the evaporation rate to not increase with increasing temperature?
The main parameter controlling 'evaporation rate' in the global meteoric water cycle the relative humidity in the source region for rainfall and not the temperature. Low humidities are associated with higher evaporation rates than high humidities. At 100% humidity the evaporation rate is zero irrespective of temperature.
The key issues are the capacity of the atmosphere to hold moisture which is temperature dependent and the temperature difference between source and precipitation regions. Just consider the Clausius-Clapeyron equation and the liquid-vapour phase boundary for water.
I love reading this blog. It's like listening to a mad uncle ranting while everyone sniggers behind his back. While you lot are arguing about whether we can say the floods are attributable to AGW, or whether there is a GE, or whether climate change is happening etc etc, the world is moving on. CoP21 is nearly ended, there is a huge global move towards renewables and away from fossile fuels and all the politicians and all the scientists accept the science. History is passing you by.
Jamesp
aTTP probably thinks that irony is what his wife does with his underpants.
Monty baby - check back in 50 years to see who history passes by. The here and now is a bit too noisy to determine the future view.
An aside, in response to 'Dame ‘barbecue summer’ Slingo is the UK's Tim Flannery' (stewgreen, 5:22 AM). I don't think that's quite the case in terms of personalities at least. Flannery comes across to me as a genuinely scared man-child with the backbone of a jellyfish, whereas Slingo seems more like a hard-headed career-woman making the most of the opportunity presented to her in a CO2-radicalised Met Office. She has operated to protect her back with qualifying phrases of perhaps this and maybe that and conjured probabilities tending one way or another, while aiming to keep the lucrative political pot of scare-soup simmering away.
aTTP, just think how much more intelligent the debate would be if Global Warmists hadn't made such stupid claims in the first place.
Perhaps you could use your knowledge of physics more constructively, if you concentrated on preventing Global Warmists from spouting rubbish and making unsubstantiated claims,, rather than attacking those who point out the piles of accumulating rubbish being generated and discarded by the warmists. It is not very kind to the scientific environment.
Dec 10, 2015 at 7:43 PM | Unregistered CommenterJamspid
Haweswater has been drained? That's news to me, also as far as I know the 'Dambusters' used the reservoirs in the Derwent valley in the Derbyshire Peak District. Haweswater is currently supplying 25 % of the North West's water (mostly Manchester I guess). A wonderful piece of engineering using gravity all the way.
Alan Ogden
Roger
"more floods in Summer"
I'd love to hear Horrorbin address that, as he's so keen on the 'warming air holding more moisture' meme. None of his colleagues thinks to challenge it, of course.
Monty, Monty, Monty
"All the scientists accept the science". WOW! Man, that is Einstein-grade reasoning. That is DEEP! Missing heat deep!
University of Sussex by any chance? Your post perfectly encapsulates the description "useful idiot".
If someone wants to know how to design flood defences that actually work, all you have to do is look at Hurst's analysis of the Aswan Dam. The design of this dam controls the floods of the river Nile admirably well over decades.
What did Hurst do differently? He understood that flooding occurs with fractal dynamics, e.g. a recent paper:
Long-term persistence and multifractality of precipitation and river runoff records
What does this mean? It means that estimates of key moments of the flood distribution (e.g. standard deviation) tend to be heavily biased as underestimates. This has several consequences: the mean flood level is poorly known at any scale, the standard deviation estimate is heavily biased (underestimated), which means what we interpret as a 1-in-100 year flood is probably more like a 1-in-50 year flood or less. Also, the fractal dynamics means extreme flood events tend to cluster.
I was shocked when I heard the flood defences at Keswick were simply set to handle a flood no larger than the last big flood in living memory. If Hurst could design proper flood defences in the 1950s, how on earth have we regressed so far in geoscience that we can't do the same thing properly in 2015?
Spence_UK
as somebody who's been involved with the Environment Agency and flood modelling in the last 5 years - I feel fairly safe saying that it's shambolic - inexperienced staff at the agency can't be trusted to handle anything - so it gets put out to the usual suspect
parasitesconsultants - who in turn are instructed about desired outcomes by EA management who are generally clueless about flooding beyond having cartoon slot machine £££ eyes about the budgets available... Those consultants it would seem by the way - still employ cheap youngsters to do the spadework and are not averse to meddling with the results at the behest of EA officials.If hubris stopped flooding - we wouldn't be here moaning - It is not a good recipe.
There has been some culling of buffoons - but mostly musical chairs and window dressing. Transparency is absolutely not a strong point of the organisation - as presently constituted.
Is this our Kenny?
http://www.research.ed.ac.uk/portal/en/persons/ken-rice(9b50cda9-01ae-4ddc-9e96-81dd0a18a5a1).html
Willing to take phd students: yes.
phd candidates willing to take Ken Rice?
??
@ Jamespid
I can find no reference to Haweswater reservoir dam being demolished.
I can find references to Haweswater supplying 25 percent of the North West's drinking water.
Haweswater Daily Mail article describes how a drowned village reappeared in 2014 (15 months ago), because of drought, presumably also caused by Global Warming.