The gathering storm

Piers Corbyn, 12 November:

At Weather Action we are forecasting at the frontiers of Sun-Earth weather and climate science and are 90% confident there will be a major storm in the period 24th-28th November and the public should be warned and preparations made. The main threat to Holland, as before, is sea defences which will be under attack from the North Storm Surge we predict - and the next one is likely to be worse than the last one.

(the blue ink is his)

Piers Corbyn, 15 November:

To The Secretary of State for Environment, Food and Rural Affairs Rt Hon Mr Hilary Benn MP

Dear Hilary,

Long range severe weather warning for UK storms in period 23^rd –26/27^th November 2007

Further to the letter I sent at the end of October warning of impending dangerous storms – including explicit warning of threats to sea defences (especially in view of new and full moon high tides at the same times) and tornado type developments in the periods 8^th-13^th November and 24^th-28^th November I am writing with an update which can help you prepare via COBR (Cabinet Office Briefing Room) for potentially dangerous severe weather which is likely to hit the UK in the period 23^rd to 26/27^th November (slightly earlier timing).

[...]

Given recent confirmation of expected developments in Sun-Earth relations we are now over 90% confident that there will be major damaging storm(s) including serious risk of breaches of sea defences* in a number of parts of the UK in the period 23^rd to 26/27^th November and therefore it is in the public interest for those involved in Emergency Services - and the public - to be given maximum advance warning. We make this information freely available in the public interest. (* NB Full Moon 24 Nov 14.31hrs).

Piers Corbyn 20 November:

Storm Update Message from Piers Corbyn WeatherAction Tues 20th Nov 2007

PLEASE PASS ON TO ANYONE CONCERNED

Citizens,

The first storm wave is now showing on forecast maps for Friday 23rd/Sat 24th Nov. AS PREDICTED.

The situation is also open for the second storm wave to follow.

We repeat our warnings

1. Standard meteorology will underestimate winds and rain even from 24hours ahead particularly for forecasts of weather in period 24th to 28th Nov.

Our estimation of top gusts over 90mph very likely in the region of the storm track remains, with 100mph likely to be topped in exposed North sea/Island/and perhaps some headland parts.

2. FORECAST USERS should note our projected storm tracks and short range information for estimating top gusts in their area. From 24 hours ahead standard meteorology will probably be reasonable about storm tracks but underestimate wind strength and rain.

The core regions under threat in our long range forecast map for Storm wave 1 remain Scotland, parts of NE England and Central/South Norway and - to a lesser extent - North Denmark.

Forecast Users in Holland and Belgium please note that they were never forecasted to be in the core storm track for storm wave 1 and will not be in it. (Wave 2 is likely to be more important in wind terms for Holland and Belgium). The main threat to Holland and the East/SouthEast coast of England from storm wave 1 (and probably also storm wave 2) will be the North Sea storm surge which will coincide with a series of exceptionally high tides - close to highest possible tides on and after 24th November.

Piers Corbyn 25 November:

URGENT AND IMPORTANT SEVERE WEATHER WARNING

You are welcome to circulate this warning as you may require

Our apologies if for circulation list reasons you receive this document twice

25th/26th Nov 2007

To Emergency Services, Local Authority Risk managers, media and WeatherAction forecast users.

UPDATE on forecast period 23-28th Nov (original central highest risk period for dangerous events) - now extended to 1st/2nd Dec

[This is a 'superstorm' period in English & US usage of the word meaning it is likely to include in the most exposed parts of main storm tracks winds gusting to over 100mph (160kph) - ie resulting from Hurricane (Beaufort Force 12 ) winds]

The period is on the 304th anniversary of the devastating Tempest of 26th/27th (modern calendar) Nov 1703 in which thousands died mainly in Bristol, the South coast of England and London, and Portsmouth was destroyed. Although there are some similarities concerning solar forcing factors of storms developments, events of that magnitude are NOT forecasted for this period.

At the time of writing (25th Nov 22.00hrs), deep low pressures are developing -as forecasted - over the Atlantic and short range standard forecasts show 'dartboard' (exceptionally deep - eg 955mb*) lows. Predicted solar effects make the present period one of rapid and accelerating weather change for the whole of the north Atlantic region from Greenland to St Petersburg and from North Norway to Belgium which will often get ahead of standard meteorology forecasts.

We continue to forecast the British Isles and the North Sea area are likely to be hit (90% confidence) by a major storm(s) and associated substorms including possible tornado type events - particularly in England - starting to show from Weds/Thursday Nov 28th/29th onwards and this or these storm systems to then move into Scandinavia in an now extended period to 1st/2nd December

Piers Corbyn 1 December:

LATEST STORM NEWS UPDATE Sat 1st Dec 20:00hr GMT
The storm now approaching is set to track on Sunday 2nd Dec through England
and into the South of the North Sea and Denmark and bring storms, damaging
winds and exceptionally heavy seas through parts of a wide area including
Ireland, Wales, England (Central, SouthWest, South, SouthEast and East Anglia),
North France (especially Cherbourg Peninsula and Normandy) , Belgium, Netherlands
and Denmark. TRAVEL is best avoided
These events are in line with WeatherAction's long range forecast for the second - 'Southerly
track' storm(s) in the extended time period to 1st/2nd Dec and the original warnings spelt out
in WeatherActions long range forecast first issued 11months ago

For those who don't know the region, the UK generally has a wet and windy period around now. The local name for this phenomenon is "winter". My own patented long-range forecasting methodology(*) enables me to exclusively reveal here, for the first time, my prediction that "winter" will return in November/December next year. With 90% probability, anyway.

(*) Sadly the margin of this blog post is too small to contain the marvellous proof of the skill of my approach.

Corbyn's May forecast

After last month's success, I'm relieved to say that things are back to normal for May, so my hat is safe from the frying pan. Remember, Corbyn forecast a cool month (0.5 to 1C below normal) with average rainfall (90-115%). Well, it turned out rather warm at 13.6C (here and here), which is more than 2C above the normal for May (about 2 standard deviations), and the rain was also clearly above his range (currently 128% at Philip Eden's site, although there is one more day to update there, which cannot bring it into the forecast range now updated to 124% for the full month). The temperature looks like it should be among the 10 warmest on record (and it could possibly be the warmest May for 160 years), although we will have to wait for the official figures to be sure.

So now Corbyn is down to a 40% success rate for the year so far (4 hits from 10 forecasts). Even if he gets every remaining month for the rest of the year perfect for temperature and rainfall, he cannot climb back up to his claimed 80% success rate.

Corbyn on July

For some reason I never saw a copy of Piers Corbyn's June forecast, so I can't evaluate that. He did breathlessly announce on the 26th (Thursday): Our long range forecast for deluges and floods between 29th June and 2nd July still stands - so Glastonbury and Wimbledon watch out! However the only report I saw about Glastonbury at that time said it was pretty dry, even sunny by Sunday, and the drizzle at Wimbledon on the 2nd certainly wasn't enough to save Andy Murray. With typical chutzpah, he is still claiming he got this right - can anyone point to any "exceptional torrential downpours" in this interval? (I'm aware of some fairly heavy rain on the 27th, I even got to enjoy it as I was in Sheffield at the time.)

Anyway, on with July. It's going to be extremely wet ("probably one of the three wettest Julys on record") with a rainfall of 160-250% of the average over England and Wales. Just to be difficult, his temperature prediction is for the daily max rather than mean as previously. This is predicted to be 0.2-1C below mean, and he also says that the mins will probably not be below normal. I reckon I can therefore reasonably assign a range of about -0.5C to +0.2C for the means (for comparison with data). If the mean is outside this range, then it is hard to see the max being in Corbyn's prediction. I think this is probably generous to him, but will be happy to hear alternative suggestions.

As well as the UK weather, he has thrown in some typhoon predictions for free. Apparently there's a 60% chance of Japan taking a hit in the first half of the month or so. No sign of them so far and it has been particularly cold here this year, although I don't know what the sea surface temperature is looking like in the formation zone.

I've been away, BTW, for those who were wondering if I'd given up entirely.

Trying to bet on climate with Piers Corbyn

Piers Corbyn runs Weatheraction, an independent and rather controversial weather forecasting operation which claims to be able to make useful long-term predictions. It's controversial because most weather forecasters do not believe there is any merit in his principles (he claims that the forecasts are based on solar output) or his forecasts. Moreover, he refuses to detail his techniques or even test his skill in any objective manner. This article puts his case, and that of his critics, in a reasonably fair way. It seems likely that much of his "success", such as it is, is based on issuing forecasts that read like horoscopes, where an optimistic assessor would find merit, but a critical assessor would find fault. Anyway, I'm not really writing about his weather predictions, but his climate forecast.

On the 2nd February 2005, he gave this presentation to the Institute of Physics Energy Management Group. It contains the following:

In the next 5 or 10 years warming is likely to be maintained as a transpolar shift occurs. This will be followed by the magnetic pole moving away from the geographic pole, a decrease in solar activity, a southward shift in the Gulf stream and considerable world cooling by 2040 AD.

Of course this forecast strongly contradicts all the projections of the IPCC. If correct, it would have almost unlimited commercial value, as it implies (among other things) that all concern over anthropogenic global warming is misplaced. I think it's fair to say that the vast majority of scientists with any knowledge of climate science would say that the forecast is nonsense. However, what matters to me is what Corbyn himself thinks.

So, I emailed him to ask him if he could quantify his "considerable world cooling", and whether he would consider a bet with me on the subject. Note that unlike the other people I have previously tried to arrange bets with (here and here), he actually makes his living out of selling forecasts, and is proud to boast of taking on the bookies and winning. So he won't have the "I don't take risks" excuse of Myron Ebell.

I've not managed to get any reply out of him at all, still less a bet. For someone who claims a success rate of 80% or more with his forecasts, he seems remarkably reluctant to make any money out of this one. Could it be ... that he knows it is wrong?

So I'm still looking for that elusive consensus-busting sceptic who is prepared to make a forecast, and stand behind it. If anyone hears of a sceptical prediction, please let me know.

Corbyn on March

I've got hold of Piers Corbyn's forecast for March. He predicts that it will be cold, very wet and slightly cloudier than average. According to Philip Eden, he's wrong on all counts at the moment.

The (in?)famous Wheeler paper specifically focussed on gales, and there was of course a severe storm a few days ago across much of the UK. So it's interesting to see what Piers predicted for that interval:

Cold with fog and frost. Some wintry showers. Wind: light/mod.

The Calcutta Cup match was supposed to be "Prob dry. 10% risk of shower."

Oh well, there's always next week to look forward to, for which he forecasts.

18-21 Mar (85%) Very wet & windy, thunder and local floods. Gales.

Corbyn's April forecast

Looks like the fun is set to continue for a little while longer, cos I've got Corbyn's April forecast. He thinks that April will be cool and rainy. This month he has unhelpfully split the Central England Temperature region into no fewer than three sections, so I'll make an estimate of the average: the SE chunk is predicted to be from -0.5 to +0.5C, the western chunk is -1 to 0C and a northern wedge is -0.8 to 0.2C - all values compared to the 1961-90 mean which is 7.89C for the CET series. So I'll take the overall average of that to be -0.75 to +0.25C and anything in that range (7.14 - 8.14C) will be a win for him. Rainfall is a little simpler, his forecast is 110-140% for the west and 95-130% for the east and north, so I'll allow 100-135% to count as a win.

As for notable events, the Grand National (5th) will be warm and dry, and the London Marathon (13th) will be positively warm or even hot. The Met Office disagrees on both counts (well they suggest the LM may be OK-ish), but what do they know?

Corbyn on February

Well I promised a post on his Feb forecast, so I suppose I ought to do something about it. Sorry for the delay, which was caused by an intrusion of real life. Even though there is nothing quite so exciting to discuss, I can't retrospectively change my mind without running the risk of being accused of the same cherry-picking that Corbyn excels at, so here goes...

In summary, Feb is supposed to be mild and generally wet. The predicted temperature anomaly of +0.7-1.7C (over the central England region) is using 1961-1990 as the baseline, which has a mean of 3.8C, so anything from 4.5-5.5C would do. Up to now it's averaged about 5.8C and the forecast is for more mild weather. I don't think I'm sticking my neck out too far in saying that there is a strong probability the month will end up warmer than his forecast. On precip he is predicting anything from 120% to 200% - mild winter weather is generally wet, but it's looking extremely dry so far so there is some catching up to do.

On the details, of course there are lots of random weather predictions that have not/will not come to pass. Remember the "severe gales" on the 7th? Nope, me neither. There are supposed to be some more happening right now, and they will return on the 21st, with the current ones "notably stormy with damaging winds espec 14th-16th in West" and the latter "High tides on new moon around 21 with heavy seas from sev gales threaten sea defences in W & S/W". We will see. I assume at least the forecast of a high tide is sound, as I used to work at the institute that generates them :-) The Scotland-France rugby match at the start of the month was "likely off" due to frost and snow, but unfortunately the French didn't read that - maybe the Scots did, cos they didn't seem to turn up for the match! His best effort so far is probably the snow at the start of the month - but he explicitly forecast Friday 1st to be dry, with the snow arriving over the weekend. Sadly for those who were trying to beat the arrival of the bad weather, it caught them on the Friday afternoon, within hours of him releasing his forecast. I wonder whether he will claim this as a hit or not.

Overall, it doesn't look good for him.

Arbitration

My reader is probably waiting with bated breath for my views on the forthcoming election. In the blue corner, Teresa “strong and stable” May (or should that be “u-turn when you want to”). In the red, Jeremy “don't mention the brother” Corbyn. In the ignored corner, Nutter and Failing and a few others.

Of course, it's all about brexit, so there hasn't been any sort of meaningful debate about this. Both tories and labour are rushing headlong for the most catastrophic outcome they can possibly engineer, and there isn't a fag-paper of difference between them on anything substantive. Corbyn promises better employment protection and May less red tape but these are not really issues of how and why we leave the EU, rather what we do afterwards. The Labour vision may be marginally more attractive but that's basically a question of what colour deck-chairs you prefer on the “Titanic Success”.

It's important to realise, there is no such thing as  a “good brexit”. The only reasonable brexit would be something functionally indistinguishable from the status quo, which both sides have ruled out. The choice is between a bad brexit, a worse brexit and a catastrophic brexit, with all the smart money on the latter. All competent experts have repeatedly pointed out the huge problems that brexit will bring, including but not limited to our European flights (there's no agreement for anything post 2019 and timetables will have to be designed well in advance of that), the operation of our nuclear industry (including such details as medical isotopes), the huge customs problem at Dover/Calais for which the infrastructure does not exist and simply cannot be built in time, the Northern Irish border which will likely spark off unification violence, the harm to our financial industry, the fact that we aren't even normal WTO members in our own right and negotiating that will take agreement from the other 162, the 759 separate agreements with 168 countries that need to be renegotiated in the remaining 661 days etc. The whole thing is idiotic nonsense and the failure of most of our politicians to say as much in plain terms is a gross dereliction of their duty.

In my opinion, the most likely outcome by some way remains a year or so of increasingly acrimonious negotiations or rather arguments, followed by a collapse of the process and long period of recrimination. This national humiliation will come at great cost of course, not just economically but also politically, culturally and socially, as we are already starting to see. Lots of people are starting to bleat about the entirely predictable consequences. I'm intensely relaxed about the poor farmers, since just about every field round here had a “Vote Leave” placard this time last year. They of all people should realise that they will reap what they have sown!

And all for what? Even though it was all about “taking back control”, no-one is prepared to make any promises about immigration anyway. For while the EU was always the convenient excuse for the large-scale immigration that govts of all stripes have encouraged over recent years, it was never actually anything more than that. They could have reduced immigration substantially had they wanted to, but they saw the obvious economic benefits of it and rather than arguing honestly in favour, passed the buck on to the EU. That is no longer possible, so we get vague ambitions which are quite clearly meant as nothing more than a dog-whistle to UKIP voters who are presumably thought to be too stupid to realise that there isn't a plan to actually do anything.

I've been enjoying the way the Tory campaign has been falling apart. “Strong and stable” has been laughed out of existence, it doesn't seem such a clever idea now to base the campaign on May's personality when it is obviously so brittle and unpleasant. Amusingly, the local election leaflet which eventually plopped through the letter box just a couple of days ago features May more centrally than the candidate himself, which should lose him some votes but I'm sure won't affect the result. As for the central conceit of May being the only person capable of negotiating brexit, if anyone seriously thinks she'll actually be PM on the day we leave the EU, I feel a wager coming on.

The only mainstream party with anything approaching a sane policy on brexit is the LibDems, so I'll be supporting them. Or rather, I would be, but they have agreed a local pact with the Greens in a neighbouring constituency (Harrogate and Knaresborough) that they won't stand here and the greens won't stand there. Think they've got the better of that bargain as H&K is at least a possible LibDem seat though not one of their top targets. So I'll be voting Green instead, the candidate seems to have made a very good impression locally (though we missed the local hustings, being in Hamburg at the time). The Greens have a very similar policy to the LibDems anyway and it wouldn't matter who stood here, the local “pig in a blue rosette” is guaranteed to be re-elected even though he was a staunch remainer this time last year.

Whither Weatheraction?

Looks like the fun is over for now, as Corbyn has stopped publishing his forecasts. Perhaps he thought his run of failures was getting a bit embarrassing. But it could just be a temporary hiccough, so I'll keep an eye out for new developments. Of course I could get the forecasts by buying them, but I'd rather drill a hole in my head than actually pay for that nonsense - and perhaps more importantly, if I actually entered into a contract then I might have to respect confidentiality clauses which would negate the whole point of the exercise.

I did find my copy of Dennis Wheeler's paper and may post on it later. But for now, you will have to put up with some poetry:

Whether the Weatheraction forecast be wrong,
Or whether the Weatheraction forecast be right,
We must weather the real weather,
Whatever the weather,
Whether Piers Corbyn predicted it or not.

Corbynwatch: The Verdict

So, January is over, and it's time to see how Piers Corbyn did. Remember, he predicted that it would be bitterly cold, in fact one of the coldest 6 years in the last 100, with an average temperature of no more than 0.8C.

The numbers are in...and the average temperature was a whisker over 7C according to the pseudo-CET web page. P Lewis says the real value is 6.7C,which would make it 5th warmest in the last 100 years, or 8th warmest in the last 350 years. Now it's important to note that I'm not claiming that this has any strong consequences for our understanding of global warming - it's just one month in one region, and in fact most of the 7 warmer Januaries were a long time ago. What it does bear on is the validity of Corbyn's "Solar weather technique" for prediction. This forecast was just about as spectacular a failure as it is possible to have. It certainly wasn't a near miss, in fact it wasn't even a bad miss. Had he been shooting for the goal at Wembley, he'd have ballooned it over the cross-bar...at Hamden Park. The 5.9C error (and note that 0.8C was the upper limit of his forecast, he said "close to freezing - 0.8C at best") is about as big as the difference between January and late April / early May. It wasn't just the temperature he got wrong, either - precipitation was not "well below normal" but actually extremely heavy, with many areas flooded.

He even revised his forecast in the middle of the month, claiming to have discovered a "data procedure error" - stirring his tea-leaves in the wrong direction, perhaps? - but even so, he blue-inked: "the forecast for some very cold weather in the later part of the month remains". Perhaps he meant to write "remains wrong". In fact the 2nd half must have averaged about 8C, since the running mean was just below 6C at that time.

But no doubt when he next makes some silly "prediction", the same journalists will lap it up and report it uncritically again. And if he keeps on predicting 5% events, then every so often one will come true, at which point he will be able to dine out on it for months...

He has just made his February forecast for the UK public. Once I've extracted the quantitative features from his vague verbiage, I'll report on that too.

Another good month for Corbyn

July was a good month for Corbyn's monthly forecast - the rainfall of 167% was in his predicted range of 160-250%, and the mean daily max (anomaly) of -0.8C was also in his range of -1 to -0.2 (data here). The various specifics were largely wrong but I can't go cherry-picking what to evaluate after the event. [I did initially say I would use mean, not max, temp but that was before being pointed to the max data on Philip Eden's broken site.]

So now he is up to 6 correct forecasts out of 12 so far this year (temp and precip for 6 months, June being curiously absent). That still represents a p-value of less than 2% based on his claimed 80% accuracy. That is, if his forecasts really had a long-run probability of 80% of validating, then the probability of getting 6 or fewer correct out of 12 is under 2%. On the other hand, it is better than chance, given that his ranges generally cover less than 50% of a reasonable climatological range. (That doesn't mean much, given that he only publishes the forecast a day or two into the month. The very heavy rain at the start of July was easily predicted by everyone at that point. Also, there is the question as to why June's forecast was not released...but there is little point in speculating on that point.)

The gathering storm (2)

I see that Piers Corbyn has started to make a bit of a habit of predicting the future, ie actually issuing forecasts prior to their validation time. While this is potentially a much more impressive feat than his previous habit of painting Texas bullseyes round the handful of events that happened to coincide with statements, selected a posteriori, that he claimed to have made some time somewhere in private, it is also riskier when repeated hysterical claims of devastation fail to be borne out. On with the game...

On the 2nd Dec he said:

Two more serious storm periods are forecast by WeatherAction for December:- Around
5th-9th and around 23rd to 26th. The 23rd-26th is likley to include storms as severe or
more severe than this one.

"this one" referred to an existing storm that he described as having "damaging winds and exceptionally heavy seas"

On the 25th Dec he said:

Update of Forecast of Storm activity during the period Dec 23^rd/24^th to 25^th/26^{th .}

^{The current situation is interesting and present forecast maps (noon 24 Dec) are not yet showing developments which are likely to occur.}

[...]

the Christmas storm is likely to be more severe and potentially more damaging –particularly to Western parts of Britain (and Europe) - than anything experienced this November / December so far or since the storms of 1987 or 1990. The Christmas storm also coincides with full moon high tides on 24^th December hence sea defences will be threatened.

Storm activity in the Atlantic and the Western British Isles is expected build up from the West from 19^th December and become significantly more ferocious and then pass through Britain during the period 23^rd/24^th to 25^th/26^th . Tornado activity is likely – probably in the South, and storm tide surges likely eg on the South coast and Bristol Channel and/or France – threatening sea defences. Top winds on land or coast in the 65mph- 95mph are likely, with higher winds associated with Storm 11 or Hurricane force 12 at sea.

Winds will be damaging, travel will be disrupted and power lines are likely to be bought down in places so it may be advisable for some in exposed parts to cook early for Christmas.

The Christmas storm will be followed after a lull by another stormy system attacking from the West just before the New Year.

Snow at Xmas?

The Great Christmas storm is likely to bring colder air from the North later so Piers Corbyn and associates with WeatherAction have staked £500 with William Hill for snow on Christmas day in parts of Scotland.

Oh dear.

I see that he is now talking about -17C temperatures in January, perhaps in the hope that this will distract people from remembering what he was saying just a few days ago.

The average temperature for January as a whole will be close to
freezing - 0.8C (33.4F) at best.

I look forward to seeing how that one pans out.

Update 8 Jan

Well Piers has sent out a rambling grumble that the press have over-hyped his prediction for January. Apparently he didn't say it was going to be one of the coldest Januaries in the past 100 years, he merely said it was going to be one of the coldest 6 Januaries in the past 100 years. Of course he has my full sympathies over this dreadful misrepresentation. It must be awful to have the press turn your words round to mean something so completely different... Their report of his actual temperature prediction above stands unchallenged.

Interestingly, the BBC monthly weather review is up for December, and inexplicably there is no mention of this dreadful Christmas storm that Piers "correctly" predicted. Perhaps everyone was cowering indoors and unable to take the measurements :-)

And finally, Piers has helpfully told us that January will probably have a spell of bitingly cold Easterly winds. I'll top that with my own personal prediction that January 2018 will also have such a spell...anyone want to bet?

Woohoo! Corbyn nails it!

Well, he got it right one month in a row. Honestly, I'm impressed. I'll be even more impressed if he gets it right for the next few months, though. For the record, April was close to average temperature and just above average rainfall, both comfortably within his predicted ranges. So now his score is up to 4 out of 8 for the year, which is still not close to his claimed 80% success rate, but slightly better than it was last month. Since it is late on a Friday night, I'll leave the binomial probability thing as an exercise for my readers :-)

Corbyn thinks that May should be about average for rain (90-115% of normal) but rather chilly, at 0.5 - 1C below average for the month. There aren't any exciting weather events forecast (you can't go far wrong with "variable: some showers" in May).

Earthquake prediction

In case anyone was wondering whether there was anything to that supposed "prediction" of the recent Italian earthquake, Piers Corbyn's advocacy of the cause should settle the matter...

"The tragic Earthquake death toll in L'Aquila Italy is due to criminal arrogance of authorities who ignored the well-founded warnings of an earthquake-scientist; and this isn't the first time that authorities and governments have ignored well-founded serious warnings based on sound science* " said Piers Corbyn astrophysicist

(blah blah blah repeat ad nauseam)

Although I have no particular expertise, I do suspect there may be something to at least some of the various "precursor" theories. However, the obvious point, as many bloggers have mentioned, is that a "warning" that is vague enough to be a week (or more) wrong and in the wrong place to boot is completely useless, even if such predictions occasionally provide enough of a coincidence to be superficially attractive. I'm not at all surprised to see Piers's enthusiasm for it, as it closely mirrors his own modus operandi.

March Corbynwatch

A quick update on the March results: Corbyn gets a fail on the temperature (he predicted colder than normal, it was warmer according to here and here - note that "normal" in his terms is the 1961-90 mean, which was 5.67C) but a success on the rain - he said upwards of 130% of normal, and Philip Eden says we had 135% (I'm simplifying Corbyn's forecast here a bit, since I don't have precise regional data). As before, I'm ignoring the sunshine on the basis that this is essentially the converse of the rainfall forecast: for the record, he was actually wrong.

So a second successive 50% result means that the scores on the doors have "improved" to 2 out of 6 for the first 3 months of the year. However, despite the higher overall success rate, the failure of his method is actually marginally more clear-cut now, since the gap between the actual success rate and the claimed 80% forecast accuracy is more apparent:

Successes (out of 6)	6 or 5	4 or 3	2 or less
Probability	66%	33%	2%

(Yes there's a rounding error there, all three values are actually a little lower than quoted.)

I hope someone will supply April's forecast. If he gets the next 7 months spot-on (temp and precip) he'll be up to the 80% rate that he claims, and I will eat my hat, video the event and post it on Youtube.

Incoming!

OK, so I admit it - I'm a narcissist. I've got a statcounter on my blog, which tells me how few visitors I get. That number is too small to be worth boasting about - I like to think of my readership as exclusive but influential :-) - but more interestingly, it also tells me where they have come from. Not surprisingly, most hits are from blogs that have a link to me, such as RC, Stoat, John Fleck. Probably some of these are readers following a regular trail through blogworld (I used to, before switching to an RSS aggregator) and others are random one-offs. Other than the climate-related stuff, a handful of hits come via the Japan bloggers webring.

Every so often, there's a flurry of hits from some much better-read source which mentions me or my "work" (does a bet count as work?), such as (in no particular order) Reason, Nature, RC, The Grauniad (try the Corbyn link). I got a startling number of hits from an on-line Polish newspaper article which mentioned the bet, which I can't find any more. But I was amazed to see that the biggest number of hits I've ever had in a day came from the recent TCS article - well over twice as many as came from the RC article that covered the same research. It's scary to think that large numbers of people might actually consider TCS to be a credible source on climate science (or indeed anything else aside from rightwingnuttery).

Outside the deliberate links, I occasionally get hits via some amusing search strings. Just about anything with a septic's name in hits one of my failed bet attempts one way or another (Piers Corbyn, Zbigniew Jaworowski, Myron Ebell, Richard Lindzen, World Climate Report) which I hope enhances their reputations. The position in these google searches goes up and down a lot, and currently several of them are not on the first page, but they are high enough to get hits some of the time. I note that the bet makes a popular talking point on various forums and blogs too. Items that I've mentioned from the Japanese press, such as marry a blue-eyed foreigner and population crash also get some hits. But, saving the best till last, my favourite is the number of people who are trying to find out how to do it doggie style, who must find this page rather....anticlimactic. Best of all, some of them have had to wade through about 8 pages of links before they get to my page (it's currently riding ridiculously high in the rankings)!

Piers Corbyn's latest "forecast"

I seem to have got on numerologist Piers Corbyn's spam mail list, which I should emphasise I have absolutely no objection to. It's amusing to see some of his "press releases" and I can always block his mail as and when i get bored :-)

Recently, he sent round a new press release proudly boasting about his success in predicting "Storm 27" in the Caribbean/Gulf area in the time window 13th-16th November. And indeed, on the surface, it looked like there could have been some substance to his claim.

The only problem is that his actual prediction was for "a major Tropical Storm or hurricane", and in fact what he optimistically called "Storm 27" was not a storm at all, let alone a major one or a hurricane, but in fact only a very weak tropical depression which died a few days later. Look here for its history, including wind speed ("DEP" in the type column is a bit of a giveaway).

Here's a picture of its track, with colour-coded wind speed:




For the picky, his original forecast actually said "around the 13-16", and you can be sure that he would have allowed himself a day or two either side if that had been necessary to score a "hit". But since he's already claimed "storm 27" as his validation, I don't think even he could have the chutzpah to claim Tropical Storm Gamma (born on the 18th) instead. I'll email him with the link to this post and maybe he will grace me with a comment.

Will the real Piers Corbyn please stand up?

Some time ago, maverick weather forecaster Piers Corbyn presented some, shall we say...unconventional...reseach concerning the supposed solar influence on climate, which, if valid, would indicate a substantial global cooling by 2040. At that time, I was still looking for an opponent to bet against. So, I tried to contact him and arrange a bet, but didn't get a response. Jim Giles, however, phoned him up while researching his Nature article, and did get him to produce the apparently unequivocal quote "I'm happy to bet loads of money".

Piers did eventually comment on my blog article (in the comments section here). I emailed him the reply which I posted below his comment, but have not heard from him again. Since he doesn't seem willing to communicate with me, I alerted William Connolley (WMC) to his offer to bet. WMC emailed him and did initially get a vague reply, which appeared to show interest, but did not address the specifics of a bet. WMC has emailed him several times over the past month, offering either to duplicate my existing bet with Bashkirtsev and Mashnich, or alternatively to negotiate something else along similar lines, but Piers has studiously avoided a direct response. He did refer to my blog article as "deceitful" and "libellous", but as far as I can see, all I have done is accuse him of ducking the challenge, and this seems to be a fair summary of the current state of play. Of course I'll be happy to help publicise any bet if only he would agree to one.

I remind all sceptics that there are offers on the table of up to 3:1 odds, depending on details such as the duration of the bet. That bookends the "market consensus" at between 2% and 25% (the lower figure referring to Lindzen's 50:1 offer). That's still quite a range (and I hope it will narrow further), but the important point, which underlies the whole "betting market" concept, is that this estimate explicitly accounts for the opinions of the sceptics. If anyone wants to take up any of these offers, or make a better one, please let me and/or the bet originators know.

A betting update

There are no new bets to report, but there has been some behind-the-scenes effort in trying to set them up.

Most of the chasing has been done by William Connolley and Brian Schmidt. In the aftermath of my bet being announced, various pundits boldly claimed that they would be willing to take the "cold" side of a bet on the same terms or similar. Chris Randles quickly took one of them on for 500 pounds, which I reported here. However, subsequent attempts to chase down the others have so far proved fruitless.

Brian Schmidt tried here, with no response so far.

William Connolley has tried to get something out of "I'm happy to bet loads of money" Piers Corbyn, but nothing's been arranged yet. He's also emailed Tim Haab and I wait to see what, if anything, transpires.

Lubos Motl made a rather childish offer that he would accept odds of 8:1 in his favour on a 10 year bet, but only so long as it used only a single year of data at each end. Of course, this makes the temperature change very noisy due to interannual variability, as you can see on the graph below:
Here I've plotted the NASA GISTEMP annual temperature anomalies, and a 5-year smoothed version (both offset by 1C). The decadal temperature changes are shown below that, with the zero line indicated. As you can see, there have been two occasions in recent decades (three if you go back as far as 1976-1966) when the 10-year change has been briefly negative even during a period which has seen strong warming. William Connolley gets a similar result using a different data set. So Motl's 8:1 offer is roughly a fair bet even under conditions of continued strong warming - hardly a sceptical viewpoint. With a 5-year smoothing filter, the cooling peaks are eliminated, but he wasn't prepared to negotiate on such a bet.

An analytical look at the data gives a similar result. The annual temperatures have a variability of about 0.09C about the trend, which means that a straight decadal difference has a variability of 1.41*0.09C = 0.13C. The trend itself is about 0.17C, which implies that under the assumption of continued warming, the overall decadal temperature change is (roughly) a sample from the Gaussian distribution N(0.17,0.13) which has a 10% chance of being negative. Smoothing substantially reduces the variability - under the (perhaps slightly questionable) assumption that the temperature anomalies of consecutive years are independent, the distribution would be close to N(0.17,0.06) which has less than 1% chance of being negative.

So, no new bets yet. But both Brian and William have now offered significantly better odds than I had to, in the hope that this might tempt some of the sceptics who merely claim that future temperature change is no more likely to be up than down, as opposed to my opponents (and Piers Corbyn) who confidently predicted that cooling was imminent. William has offered 7:3 for an unsmoothed decadal difference. Brian has offered 2:1 on decadal bet, and 3:1 over 20 years. Until and unless they find any opponents, it seems reasonable to conclude that whatever the market rate is, it is higher than those offers on the table.

PMIP at Crewe

We've been back well over a week, so the trip report is well overdue.

The main excuse for our recent lengthy UK trip was the PMIP meeting in Crewe. Although we had originally planned to combine this with the EGU in Vienna two weeks earlier, this didn't happen for a number of reasons. I should probably call the meeting PMIP3, as this is the third iteration of the project, but really the scientific content covered a lot of PMIP2-related work (including ours) and some stuff that isn't really PMIP at all, at least in the strict sense of modelling one of the handful of specific eras with community-defined boundary conditions. To be honest, although there was plenty of generally interesting stuff, there wasn't a great deal that struck me as particularly exciting or noteworthy at least in the context of my own area of research. I liked Sandy Harrison's presentation which summarised her huge effort (with others) in generating model(er)-friendly sets of paleodata which can be used to test climate models. I also had a lot of good conversations regarding my poster, which will lead to further analyses and hopefully improvements of the paper which is mostly written. I'll blog about that at a later date. The posters were up all week and located in the coffee area, so it was easier to have good discussions than is often the case. So it was a very useful week for me.

The contrast with Gavin's workshop in Hawaii was surprisingly large - the latter was much more focussed on actually using the past for informing on the future (eg validating/constraining model predictions) whereas PMIP has many more people who pay lip-service to this goal, while they really just look at the past because it is interesting science. I'm not meaning to be too critical of their approach, it's an entirely reasonable thing for an academic to do, so long as not all of them do it! There were also some general concerns expressed at the lack of "climate prediction people" at the workshop, but it seems to me that the links between PMIP and CMIP are continuing to strengthen gradually, and since this is the first time that PMIP simulations have been officially included in the CMIP experiments, it's hardly surprising that the communities are still somewhat disjoint. On the other hand, it was disappointing that there was no-one at all from the Hadley Centre, who seem to have basically given up paleoclimate modelling, just as the rest of the world is getting properly interested in it. GISS was another notable absentee - I'm guessing in this case it was just due to overcommitment or clashes, as several of them have generally been very active. Other than that, there was a good attendance, especially (and unsurprisingly) from the UK. So while we could have made a longer work trip out of it, our decision to not trip around the country to visit different institutes seemed pretty well vindicated. Plus, flying into Manchester made it easy to avoid Heathrow Airport which is never a bad idea.

The venue was great. PMIP has a history of somewhat exotic locations (previously Kyoto and before that Estes Park in the Rockies), and for this meeting we had originally been threatened with a Scottish castle in February (it seemed to me that everyone who had actually been to Scotland in February objected vociferously to this absurd proposition, but we were a small minority and outvoted). Fortunately, it proved impossible to find such a site, and Crewe Hall in May made for an excellent alternative. Until quite recently an elaborate stately home, it is now a modern hotel with excellent conference facilities. We spent most of our time in the modern bit, with the conference dinner and ceilidh in the old bit. Quite by chance, most of the organisers and their friends were also staying in the historic rooms too :-) Next time looks like it will be in Belgium, courtesy of Michel Crucifix. He promises it will not be in Louvain-la-Neuve.

Along with the work, we had holidays in Lancashire and Scotland, which were great (as you may have guessed from the pictures), but could have been just a little warmer. Not that the weather was anything like the record-breaking cold temperatures that Corbyn predicted, so no doubt he is busy hunting for cherries to pick out of the wreckage of his forecast, or re-painting his bullseye somewhere in the vicinity of the data.

Now we're back in Japan with the small matter of 5 papers to finish before 31st July...