Slingo Pretends She Knows Why It’s Been So Wet!
By Paul Homewood
Following release of provisional rainfall data for the UK, showing that 2012 has been one of the wettest on record, Professor Julia Slingo, chief scientist at the Met Office, tells us
“The trend towards more extreme rainfall events is one we are seeing around the world, in countries such as India and China, and now potentially here in the UK”, adding that “the long-term trend towards wetter weather is likely to continue as global air temperatures rise. “
Leaving aside the fact that the Met Office have also been warning us about droughts lately, let’s take a look at some of the forecasts they were making during 2012.
Each month they issue a 3-month outlook. Unfortunately the ones issued prior to September have disappeared from their archives, but I had already saved the April-June, and also the Sep-Nov forecasts. Along with the Oct-Dec ones, what were the Met forecasting as the year progressed?
On 23rd March, they predicted “The forecast for average UK rainfall slightly favours drier than average conditions for April/May/June as a whole, and also slightly favours April being the driest of the 3 months.”
RESULT – RAINFALL TOTALS WERE 176%, 94% AND 203% OF NORMAL IN APRIL, MAY AND JUNE RESPECTIVELY.
http://www.metoffice.gov.uk/media/pdf/p/i/A3-layout-precip-AMJ.pdf
On 24th August, their forecast for September “weakly favours below normal values”.
RESULT – RAINFALL WAS 117% OF NORMAL IN SEPTEMBER.
http://www.metoffice.gov.uk/media/pdf/i/e/A3-plots-precip-SON.pdf
On 21st September, they said “For UK-averaged rainfall the predicted probabilities favour below normal rainfall during October. For the period October-November-December as a whole the range of forecasts also favours lower than average rainfall”
RESULT – RAINFALL WAS 101% OF NORMAL IN OCTOBER.
http://www.metoffice.gov.uk/media/pdf/h/g/A3-plots-precip-OND.pdf
On 24th October, they forecast “Predictions for UK-mean precipitation for both November and the November-December-January period are similar to climatology”
RESULT – RAINFALL WAS 111% OF NORMAL IN NOVEMBER.
http://www.metoffice.gov.uk/media/pdf/q/6/A3-plots-precip-NDJ.pdf
And on 20th November, “Predictions for UK-mean precipitation for December show a slight shift towards below-normal values – consistent with negative North Atlantic Oscillation conditions”
RESULT – RAINFALL WAS 150% OF NORMAL IN DECEMBER.
http://www.metoffice.gov.uk/media/pdf/j/i/A3_plots-precip-DJF.pdf
So for the seven months between April and December, that forecasts are available for, the Met Office forecast drier than normal conditions in six, and normal in the seventh. They failed to get any month correct, and for the seven months in question, rainfall averaged 36% above normal levels, (which are based on 1981-2010.)
http://www.metoffice.gov.uk/climate/uk/anomalygraphs/2012/2012_Rainfall_Anomaly_1981-2010.gif
It is very kind of Julia to tell us now that she knew all along it was likely to be wetter. It is just a pity, though, that she forgot to tell us at the time.
Trackbacks
- UK Rainfall 2012-The Report The Met Office Should Have Produced | Watts Up With That?
- UK Rainfall 2012: The Report The Met Office Should Have Produced | The Global Warming Policy Foundation (GWPF)
- Inside the new climate row as Mystic Met Office goes cool on warming | Technology News
Comments are closed.
NOT A LOT OF PEOPLE KNOW THAT 
Paul,
amazingly I saved the ones you are missing – will send by email.
Great!
Yes, I don’t recall that during the drought period, the MO were telling us not to worry, because there would be a lot of rain later in the year.
We were being told that it might take years to re-fill the aquifers and there was talk of building pipe-lines to transport water around the country.
The MO increasingly tends to be “wise after the event”, forecasting for the future, what has just happened.
I imagine that future 3-month outlooks will be predicting above average rainfall for a while.
Excellent. Very funny!
Very well put together. And damning.
If it were just boffins making fools of themselves …. But weighty decisions result from their bumbling. If accountability ever meant anything, it should apply here. Heads should roll. “Und wenn die kopf fällt — Hup-la!”
edit; I was sure it was “die”, but Google tells me it’s “der Kopf”. Missed the capitalization, too.
(The original is from “Jenny, Pirate Bride”, in Die Dreigroschenoper. Fantasizing having the entire population of the town where she works as a hotel maid beheaded by her pirate captain lover.)
All those rainfall numbers look like large anomalies but one has to remember that rainfall is highly variable. It can also be very localised (individual cu-nims do not cover large areas in UK, nor do they form large groups, unlike the US). Increasing the number of rainfall measuring stations is only likely to lead to capturing more of the heavy, very localised events (ie scaring yourself).
I have only looked at historic data from Southampton but for that town anything less than at least 250% of normal is not very unusual. There is about a 5% chance of exceeding a 200% anomaly in any month in the last 150 years and there will be, in general, one 250% anomaly in each month in the last 150 years (for Southampton (station closed in 2000 )).