October 2017 – very mild by night so far

The first two weeks of October have been very mild across the country, but not particularly by day, because day time maximum have remained close to average, but by night, where some places have seen minimum temperatures [18-06]  as much as 3°C above the long-term average (fig 1).

Figure 1

There have only been a few ground frosts across the British Isles so far this month, and those were mainly in the northeast and central Ireland (fig 2), it looks like it could be yet another mild Autumn the way things are going.

Figure 2

Incidentally, if you do find that I leave Scotland out of a map in any of my articles, please let me know and I will add one, it’s just that monitors favour landscape rather than portrait orientation, and when I zoom in to get extra detail,  something has to go.  As far as I know, I have just the one subscriber from the north of the border at the moment.

BBC News: Bid to rescue Ben Nevis weather data

Figure 1 – Courtesy of the BBC

Believe it or not, the hourly weather observations from Ben Nevis from 1898-1902 have still not been digitised. It’s a real shame that the Met Office haven’t already done this on behalf of the nation, instead of relying on volunteers at Weather Rescue to do it for them (fig 2). But then again, they have their hands full, because they still have at least fifty years of climate records that the Victorians left them that also need digitising, because at the moment their climate records only extend back to 1910 for temperature and rainfall, and 1929 for sunshine. It’s not that the Met Office haven’t been round for all that length of time because they were established in 1854 as a small department within the Board of Trade by Vice-Admiral Robert FitzRoy, it’s just that when they did discover computers, they were too busy doing other things with them to bother adding the climate records that they held in the archives.

Figure 2 – Weather Rescue

Personally I think as much effort that’s gone into digitising these records, ought to be put into to reestablishing the Observatory on top of the Ben. Well not exactly Observatory such as the Victorians built, more an automatic weather station, similar to the one on top of Cairngorm. I realise that there’s already a SIESAWS on Aonach Mor just across the Coire Leis from Ben Nevis, but its lower (1130 M), and simply doesn’t have the prestige of being sited on top of the highest mountain in Britain gives it. Power to the AWS would obviously be the main problem, and an extension lead 4,411 feet in length would simply be out of the question. Solar panels may help a little, but they would ice up easily and disappear under rime for most of the winter. A large rack of lithium-ion batteries may do it, but who would pay for them to changed by helicopter every month. A small wind turbine might do it but that again would ice up, maybe eventually some kind of fuel cell might be the answer for these remote places.

This is what the directors of the Scottish Meteorological Society said about the closure of the Ben Nevis Observatory in 1904:

“It is to the Directors a matter of profound disappointment that in this wealthy country it should have been found impossible to obtain the comparatively small sum required to carry on a work of great scientific value and interest, and that they are now obliged to dispose of the Observatory buildings and dismiss the staff”

It seems that little has changed in the last hundred years or more since its closure.

So if you have an hour to spare, why not volunteer your time to help digitise the Ben Nevis observations? I’m sure it won’t be long before the Met Office, in these days of financial austerity, see the potential in this idea, and will open up their archived observational records to volunteers to be digitised too!

Met Office : Earlier budburst linked to warmer springs

I have a book in my library entitled “Weatherwise – England’s weather through the past thirty years‘ by John H Willis and published in 1944. John Willis who died in 1962, kept faithful records of temperature, sunshine and rainfall for many years and took photographs of trees on the same day each year. Strangely his work on phenology, which has been largely forgotten these days, came to a similar conclusion as this joint study between the Met Office and Woodland Trust did. I don’t think somehow that these results will come as any great surprise to people who love the weather and the countryside.

Figure 2

This is a graph and table (figs 2 & 3) from a study that I did myself using daily CET data earlier this year, to see just how much earlier the first day of spring was occurring in 2017 than it was in 1772. I reckon that the first day of spring now occurs three weeks earlier than it did in 1772 in Central England.

Figure 3

 

 

Autumn is on it’s way – the last 8,760 hourly temperatures at Exeter

Figure 1

Ever wondered what a scatter graph of hourly temperatures for a year looks like? The chart above (fig 1) does exactly that for Exeter airport, along with a 24 hour (black) and 7 day centred moving averages to boot. The cool morning temperature of 5.8°C from the airport, reminded me that Autumn is on its way, even though for the first few days of the coming week 1000-500 hPa partial thicknesses will be in excess of 564 dm. The 7 day moving average which peaked in June at close to 20°C, and has been declining erratically since the middle of July.

Figure 2

The sunshine stats may well be a little low for Exeter, with an annual total of just 1414.3 hours, this is because the sunshine record is not 100%. There are occasionally missing values from the SYNOP reports that I can do little about, December 2016 had quite a number, and might explain the odd behaviour of the moving average (fig 2). Even so, the sunny spells that did occur in early April, and in the second half of May are clearly visible, as is the warm and sunny June in both temperature and sunshine graphs.

State of the UK Climate 2016

The Met Office have just released the third edition of their State of the UK Climate for 2016. I always find that this a strange time to publish such a document, why not by the end of January? But once you have taken a look at the 59 page document, you’ll see that it must take a lot of work to put it all together, and I am just being my old curmudgeonly self.

There’s an interesting correction at the foot of the article about CET, which as most of you know is something I like to talk about at length. I find it amazing how people scour the climate datasets to pick out a new extreme, be it high or low, this one’s no exception – decades that span 10 years but don’t start on a year that ends in a zero aren’t what I would call a decade. It’s time to see what the Collins dictionary definition of a decade is:

A decade is a period of ten years, especially one that begins with a year ending in 0, for example 1980 to 1989.

So they are strictly correct, but personally I still like to think of a decade as a period that starts with a year that is divisible by 10 without a remainder, as the Collins dictionary definition suggests it is. Anyway back to the correction, what they were initially said was that the period 2007-2016 was the warmest ‘decade’ in the whole series back to 1659. Obviously they noticed that something was wrong, and said it was incorrect. I wonder why they didn’t just delete the reference in the HTML? I was certainly late on this one and never saw the original.

Just out of interest, here is a centred 10 year moving average of monthly CET values since 1900 (fig 2), and as far as I can see, the warmest decade was the one from 1997 to the end of 2006, when the mean 10 year anomaly for the first time just exceeded +1.0°C, since then, Central England has cooled, until about 2012, when annual anomalies increased sharply again. I think the reason they corrected the original article could have been for a typo, because 2007-2016 and 1997-2006 are just ten years apart. They can always ask me to provide them with graphs, I have a graph of CET values to suit just about any occasion, and the bonus is that I work cheap.

Figure 2

Here for completeness is the full 10 year series of moving averages since 1659 (fig 3).

Figure 3

And finally the infographic that the graphics team have produced to advertise the publication of the 2016 report is a bad idea to my mind. I love a well designed infographics – you only have to look at my blog to see that – and I do realise climate statistics are not the most exciting things to try to visualise, but a clear well constructed table or graph is really all you should need. Most of us have moved on from kindergarten I would have hoped, but they may have been instructed to produce a simple infographic for politicians the like of Michael Gove to understand what’s going on.

Figure 4 – Courtesy of the Met Office

High risk of unprecedented rainfall

Figure 1 – England Wales Precipitation (October – March) 1766 – 2016 – data courtesy of the Met Office

Dr Adam Scaife has been at it at the Met Office again, or more correctly I should say that Dr Vikki Thompson the lead author of the report ‘High risk of unprecedented rainfall in the UK in the current climate‘ has. News of her findings are in the latest Met Office blog, in which she says:-

“Our computer simulations provided one hundred times more data than is available from observed records. Our analysis showed that these events could happen at any time and it’s likely we will see record monthly rainfall in one of our UK regions in the next few years”

According to the article:-

“Analysing these simulated events showed there is a 7% risk of record monthly rainfall in south-east England in any given winter. When other regions of England and Wales are also considered this increases to a 34% chance”

I can’t totally agree with her when she says in the included video that:-

“…older records are now no longer so relevant to the current risk because climate has changed over the past century”

My question to her would be – “why do we know climate has changed?” – the answer to that is because we already have existing rainfall data back to 1910, wouldn’t it then be wise to digitise all the rainfall data that the Victorian’s collected from 1859, and just see how unprecedented (and believable) the rainfall events that their new supercomputer has generated?

Sometimes I think that the NWP programmers have taken over the asylum Met Office, rather than the climatologists taking the lead in these investigations, or perhaps they’ve fused together as one being that does both.

They maybe onto a winner with this one though, because a quick look at the “real” (or as close as we are going to get it) gridded England Wales Precipitation from 1766, and the simple linear trend is definitely upwards and wetter by 22.7% in those 250 years (fig 1). If the total rainfall across the October-March period has increased, then you would logically infer that the number of unprecedented months has also increased.

The article goes onto say:-

The authors have named this novel research method the UNSEEN method to emphasize that this analysis anticipates possible events that have just not yet been seen.

I can’t see a link to the report that they are talking about in the blog, so it maybe that they’ve applied the “unseen method” to that, and we are to rely on the infographic (fig 2) for people with really short attention spans like myself.

Figure 3 – Courtesy of the Met Office

So if Climate change is likely to increase the frequency and magnitude of severe flooding events as many people think, why has rainfall declined, and not increased in the other half of the year? I reckon that April to September precipitation is 13% lower than it was 250 years ago (fig 3). But of course older rainfall records are now no longer as relevant these days, because the climate has changed so much, and we should probably just disregard it.

Figure 4 – England Wales Precipitation (April – September) 1766 – 2016 – data courtesy of the Met Office

What’s the sunniest month of the year?

I thought that I would investigate and find out exactly what climatologically is the sunniest month of the year using monthly sunshine data from the Met Office. The gridded sunshine record only started in 1929, but I’ve been reliably informed by someone in the know at the Met Office, that plans are well advanced to extend this (along with the rainfall and temperature series), back to at least the start of the 20th century, which I applaud, although in my opinion it’s a long way overdue. The add-on to my application looks not only at sunshine, but rainfall and temperature too, and for any region within the United Kingdom. The pie chart I’ve include is for England & Wales (fig 1), and reveals, surprisingly to many I bet, that May is climatologically the sunniest month of the year in 35.2% of years since 1929, followed by June in 31.8% of years, and July in 19.3% of years.

Figure 1 – Data courtesy of the Met office

Also rather surprisingly, it can happen that in some years April is the sunniest month. According to my application that’s occurred five times, in 1945, 1954, 2002, 2007 and 2011, so three times in the last 15 years. There’s always a chance that I’ve made an error let me know if I have.

The sunniest month in the entire England and Wales record was the July of 2006 with 287.6 hours of sunshine (fig 2). The sunniest month in the famous summer of 1976 was also a July with 251.5 hours of sunshine, but ranked only 13th in the list of sunniest months in a year.

Figure 2 – Data courtesy of the Met Office

The sunniest May’s in the UK since 1929

What was the sunniest May in the UK? That of course depends on where you live, so using the regional gridded sunshine data series from the Met Office that started in 1929 here is a map of the sunniest May for each of the nine individual regions, and for the whole series in a horizontal bar chart (fig 1). May is climatologically the sunniest month of the year in the UK, but more of that in an upcoming post, and by the look of it, the May of 1989 was the sunniest in nine of the seventeen regions, including the UK and England and Wales, if the gridded sunshine values are anything to by.

Figure 1 – Data and map courtesy of the Met Office.

The 1989 record certainly is in no danger of being broken in the southeast this year, but it’s certainly could in Northern Ireland and the west of Scotland, where they’ve got off to a flying start (fig 2).

Figure 2

April sunshine totals 1981-2010

Figure 1

The sunniest place on average in the UK in the period between 1981 and 2010 is Shanklin on the Isle of Wight with 201.4 hours. In fact most of the climate stations in the top 17 can be found on the English Channel coast somewhere. On the southwest peninsula the fall off in sunshine the further away from the coast you are looks to be around 10%. The Met Office provide these 1981-2010 average in their DataPoint web service and are not neither straightforward to download or to parse, because they’re all in XML format and come as individual files for almost 300 locations. The things I have to go through for a climate story.

Figure 2

I contacted the Met Office at Jersey yesterday and asked them what their record highest April sunshine total and got this tweet back.

Figure 3

I make their total for the same period 249.5 hours, yesterday they had another 2.5 hours taking them up to 252.0 hours. I’ve tweeted the Met Office at Jersey and asked them to check their total, but so far have had no response. As far as I can see I’ve done the maths correctly, and my old maths teacher Mr Brightmoor I’m sure would have been proud of me. The 1981-2010 average for Jersey is 196.5 hours in April, so that makes the latest anomaly just over 28% above the average.

Figure 4

A little white lie from the Met Office

Quite a lot of things annoy me about the Met Office as regulars readers of this blog will have no doubt picked up over the years. One of the worst traits that they have, is when talking about climate statistics for the UK, they use the following phrase:

“When records began in 1910…”

When you know full well that detailed records existed much earlier than that. What they ought to say, which is much close to the truth, is:

“We’ve only managed to digitize records back as far back as 1910, and even though we hold detailed climate records that go as far back as the early 1850’s, we can’t be bothered to do anything with because we’ve already spent the money on a big new shiny supercomputer.”

There is a classic example of that on their website today concerning the occurrence of frost in the UK during April.

Figure 1 – Courtesy of the Met Office

“Detailed frost recording in the UK began in 1961”. What a shocking admission for the national weather service of a country that was established in 1854. That must mean all of the sterling work done by meteorologists before 1961 was all in vain and a complete waste of time. What happened to all the temperature records between 1854 and 1960? At random, I picked out a copy of the DWR for January 1917 just to see if there were any extreme temperatures reported back then, and unsurprisingly there they were, for thirty-three stations across the British Isles (fig 2). Of course that’s just the tip of the iceberg, because like today, many more climatological returns from stations remain unpublished and go straight into the archives.

Figure 2 – Courtesy of the Met Office ©Crown Copyright

Absolutely no excuse

The Met Office were one of the first big users of computers and still are, here is a list of the computers that they’ve used down through the years (fig 3). I realise that looking forward with NWP model is vital, but so is looking back, and treasuring the climate data that previous generations have made since 1854. But why is it that climate records have always seemed to have been neglected, and climate data limited and inaccessible when there seems to have been no lack of one of the world’s fastest supercomputers at their disposal?

Figure 3 – Courtesy of Wikipedia

The Met Office have the resources, both in terms of staff and computing power to digitize the rainfall, temperature and sunshine records of the past and extend the gridded data series that they already have, back at least 50 years before 1910, but they have chosen to leave that wealth of old climate data untapped, and for the life of me, I just can’t understand why?