What did El Nino 2015 Contribute to the ‘Hottest Year Ever’?

There’s been quite a lot of excitement in the media and on Twitter following announcements by NASA and the Met Office that 2015 was the hottest year ever recorded ‘by some measure’. In particular, the debate has centred around how much El Nino contributed to the ‘record hot year’ (not evident at all in the lower troposphere satellite data) and how much man-made global warming was responsible. Given that global mean temperatures usually show a delay of several months after El Nino peaks, it seems reasonable to suppose that 2016 will peak higher than 2015.

So, we might expect that in 2015 the contribution from El Nino would be modest. The satellite data confirms this: we see temperatures rising steadily throughout the year but failing to exceed 2010 or 1998.

msu20rss20globalmonthlytempsince197920with37monthrunningaverage20with201505reference

It is very likely that RSS/UAH will continue to rise sharply in the first few months of 2016. The million dollar question of course is: will 2016 exceed 1998 to become the hottest year in the satellite data series? The multi-million dollar question is: will El Nino 2015/16 ‘step up’ global mean temperatures to a new level or will the inevitable follow-on La Nina be very deep and ‘step down’ global temperatures? For it should be obvious by now that ENSO is the vehicle whereby global warming/cooling is expressed – not the driver of warming/cooling, I hasten to add.

So anyway, logic tells us that, for 2015 at least, El Nino might only have contributed to a modest rise in GMST. Peter Stott of the Met Office says that El Nino contributed a “small amount on top”, although it’s not clear if this ‘small amount’ is to the 1C total rise since pre-industrial times or just to the spike in temperatures that the surface datasets show for 2015. I think most sceptics are interested in what the contribution might be just to the ‘spurt’ in global temperatures between 2014 and 2015, which, according to the Met Office, amounted to 0.18C. According to NOAA, the increase was a staggering 0.29C and NASA put the figure slightly less at 0.23C. Of course, we can rely upon that all-knowing Oracle of Global Warming, the Guardian to give us the lowdown on this vital question:

“A strong El Niño event is peaking at the moment, putting the “icing on the cake” of high global temperatures. El Niño is a natural cycle of warming in the Pacific Ocean which has a global impact on weather. But scientists are clear that the vast majority of the warming seen in 2015 was due to the emissions from human activity.

“Even without an El Niño, this would have been the warmest year on record,” said Prof Gavin Schmidt, director at Nasa’s Goddard Institute for Space Studies. He said he expected the long trend of rising global temperatures to continue because its principal cause – fossil fuel burning – was also continuing.

“It is clear that human influence is driving our climate into uncharted territory,” said Prof Phil Jones, from the University of East Anglia’s Climatic Research Unit, which produces the temperature record – called HadCRUT4 – with the Met Office.”

I agree. Even without El Nino, 2015 would probably have been a record breaking year in the surface datasets. What I am more sceptical about is whether this contribution to record breaking warmth has come from man-made global warming or man-made temperature adjustments (courtesy of Karl et al for NASA/NOAA)!

Let us abandon the flights of fancy of the Guardian and Gavin and come back down to earth with the realisation that ENSO does contribute to global warming. the Met Office tells us that El Nino 1997/98 elevated global mean temperatures by ‘at least 0.2C’:

“The major El Niño of 1997/98 elevated the global mean surface temperature by at least 0.2C. Since then the increase in global mean surface temperatures has been small and this has been linked in part to decadal changes in the circulation of the Pacific Ocean”.

What is important to note is that this was after the La Nina which followed. 0.2C was a measure of how much ENSO ‘stepped up’ global temperatures. This is very different from what sceptics and AGW convinced scientists are squabbling about on Twitter, i.e. the transient contribution to GMST from an El Nino happening now. In 2016 the transient contribution to GMST and LT temperatures may be very significant – much more than a few tenths of a degree perhaps – but the question is how will the global climate system setlle down after El Nino/La Nina? That is the really interesting question. Will we see a new ‘high’ established, from which point presumably global warming will take off again in earnest, or will we indeed witness global cooling in late 2016, on into 2017/18?

Correction:

According to GWPF:

Nasa says that 2015 was 0.13°C+/-0.10°C above 2014. The UK Met Office said that 2015 was 0.18°C +/- 0.10°C above 2014. Noaa says 2015 was 0.16°C+/-0.09°C warmer than the previous record which was 2014.”

 

Final Word on the ‘Unprecedented’ Rainfall of December 2015

So, it’s official, December 2015 was the ‘wettest ever’ [smallprint: ‘in the UK record going back to 1910’]. Much fanfare at the Met Office, Guardian, Indie etc., blah, blah, blah. It beat 1929 to the top spot and ‘though El Nino undoubtedly played a part, such events are predicted to become more common as climate change (TM) progresses because of simple physics’ – the well worn statement of implicit attribution combined with appropriate caveat and unassailable ‘scientific’ logic is now very boringly familiar to most.

uk

So, yes indeed it was the wettest December in the UK since 1910, but is there a trend? Hardly, looking at the graph above. Decembers were wetter in the early 20th century, then they got drier and from the 1970’s they’ve got progressively wetter again – but not significantly wetter than they were in 1910 (one record does not a significant rising trend make). If we look at each country of the UK, we see in fact that England has in fact become drier in Dec since 1910:

england

Whereas Scotland shows the only really significant increase in precipitation in December:

scotland

The EWP record which goes back to 1766 and which has not been referenced by the Met Office and alarmist press as far as I know, shows that December 2015 wasn’t even a contender for a top spot, exceeded in the record by numerous other years and coming nowhere near the record set in 1876.

ts_ewp_decemberThus we must conclude that, for whatever reason, the ravages of climate change have not been visited upon the Sassenachs!

But I hear them say in climate alarmist land: “Ah yes, but the rainfall intensity in the north and Scotland was unprecedented!” followed by, “We expect this due to climate change and simple physics” . . . blah, blah, blah, etc. etc. etc. Well, OK, yes, it seems that records were set at individual weather stations and the biggie was at Honister Pass – 341.4mm of rain in a 24 hour period (a new UK record). But all may not be as it seems. You see, a ‘day’ of rainfall has traditionally been measured from 0900 GMT to 0900 GMT. I quote:

“The 09-09 GMT record is important because from a historical context much of the data is daily data recorded over the standard 09-09GMT period.”

[http://www.itv.com/news/border/2015-12-07/storm-desmond-breaks-uk-rainfall-record/]

So even though Dec 2015 set a record for most intense rainfall in any 24 hour period (a relatively recent method of measuring rainfall), it failed to set any records for a traditional rainfall day. The records still stand as follows:

Highest 24-hour rainfall totals for a rainfall day (0900-0900 GMT)

Country Rainfall (mm) Date Location
England 279 18 July 1955 Martinstown (Dorset)
Scotland 238 17 January 1974 Sloy Main Adit (Argyll & Bute)
Wales 211 11 November 1929 Lluest Wen Reservoir (Mid Glamorgan)
Northern Ireland 159 31 October 1968 Tollymore Forest (County Down)

All of them, you will note, set 1974 or earlier, gong back to 1929. 2015 did manage to set the record for rainfall in a traditional 2 day period though, which now stands at 405.0 mm measured at Thirlmere, Cumbria. This was the only recognised traditional short period rainfall record set in December 2015. If we look at periods shorter than 24 hours, Dec 2015 doesn’t even get a look in.

UK rainfall records for short durations

Minutes Rainfall (mm) Date Location
Highest 5-minute total 32* 10 August 1893 Preston (Lancashire)
Highest 30-minute total 80 26 June 1953 Eskdalemuir (Dumfries & Galloway)
Highest 60-minute total 92 12 July 1901 Maidenhead (Berkshire)
Highest 90-minute total 117 8 August 1967 Dunsop Valley (Lancashire)
Highest 120-minute total 193# 19 May 1989 Walshaw Dean Lodge (West Yorkshire)
Highest 120-minute total 155# 11 June 1956 Hewenden Reservoir (West Yorkshire)
Highest 155-minute total 169 14 August 1975 Hampstead (Greater London)
Highest 180-minute total 178 7 October 1960 Horncastle (Lincolnshire)

* Approximate value.

# Reservations about Walshaw value, Hewenden value is next highest accepted value.

So much for the expected increase in intense rainfall. You will note that most of the shorter period records are set in summer, as one would expect with strong convective heating. But even so, the most recent year in which an intense short period rainfall record was set is 1989. The rest go way back as early as 1893.

So overall, we’re not seeing evidence of December being particularly exceptional in terms of monthly totals or shorter period more intense downpours. Not exactly what the alarmists want the world to hear.

Betting on 2016

Mark Boslough recently issued a ‘challenge’ to ‘deniers’ to bet against him that 2016 would not be a record breaking year in the GISS dataset, hotter even than 2015, the current ‘hottest year ever’. He seems to think that this single event will confirm that “global warming is real”. Strange man. Anyway, with a very strong El Nino (now peaked), it is virtually certain that global temperatures will peak (naturally) in 2016. Furthermore, with the GISS incorporating NOAA’s ‘pause-busting’ SST data, it is highly unlikely that 2016 will not turn out to be another ‘hottest year ever’. So no sceptic worth their salt is going to take that sucker bet.

A more interesting bet would be whether 2016 will exceed the warmth of the current warmest year (1998) in the RSS and UAH satellite datasets. RSS data for December 2015 is in; anomaly is 0.54, up from 0.43 last month.

rss_ts_channel_tlt_global_land_and_sea_v03_3

RSS Lower Troposphere Global Temperature Anomalies

Mark Boslough wasn’t interested in taking up my offer of betting on this far less certain occurrence – surprise, surprise.

My personal opinion is that it’s entirely possible that 2016 will not turn out to be the warmest year in the satellite data. Even though, in terms of Nino 3.4 SSTs, the 2015 El Nino was more powerful than 1997, Nino 1+2 regions lagged quite a bit behind.

02-weekly-nino-region-evolution

In this respect, the 2015 El Nino, for my money, resembled more a Central Pacific (Modoki) type El Nino than it did the 1997 very powerful canonical El Nino. Note also that Nino 3.4 in 2015 started nearly 1 degree higher than 1997, courtesy of the strong Pacific warming in 2014. The Met Office has a very interesting analysis of El Nino events, in which they say:

“The major El Niño of 1997/98 elevated the global mean surface temperature by at least 0.2C. Since then the increase in global mean surface temperatures has been small and this has been linked in part to decadal changes in the circulation of the Pacific Ocean. It has also been noted recently that CP El Niño events do not have the same impact on global mean surface temperatures as EP El Niño events; global mean surface temperatures are, typically, anomalously warm during and after EP events, but not in CP or mixed CP/EP events. It is also the case that since 1998, El Niño has been dominated by CP events, and this recent paper suggests that since the late 19th century, periods of slowdown in the rate of global mean surface warming typically contain only CP El Niño events, and no EP events”.

It would not surprise me therefore if 2016 fails to exceed 1998 as the warmest year recorded in the satellite data series. What of 2016 and beyond? There are three possibilities: the expected spike in global temperatures may initiate a ‘step up’ (like 1998 did), it may not affect global temperatures significantly, in which case the current Pause will continue, or it may initiate a ‘step down’ in global temperature via a very deep subsequent La Nina cooling. If we’re betting, my money is on the latter in late 2016/early 2017. If we get another ‘step up’ in global LT temperatures, I will be the first to admit that the anthropogenic CO2 warming theory may have something going for it, because many current climate indicators (AMO/AMOC/solar) point to imminent cooling.

Update: 05/1/2016

Bob Tisdale has posted an updated graphic to the one above:

nino-region-evolutions

We can see that El Nino has clearly peaked in all regions. Nino 1+2 regions peaked considerably lower and several weeks earlier in 2015 than they did in 1997 and they are now declining quite rapidly. We shall soon see if this affects any resultant spike in global temperatures in 2016.

More on the ‘Unprecedented’ Rainfall Causing UK Flooding

In response to me linking to my latest blog post on Twitter, BBC weatherman and meteorologist Simon King pointed me to this graph of UK annual rainfall  since 1910 which shows a significant increase in trend since 1980 – a point which he made when being interviewed on BBC FiveLive apparently.

uk

Aside from the fact that the UK series is very much shorter than the EWP which goes back to 1766, there is indeed a marked positive trend in UK annual rainfall, starting around 1973, and exceeding that of 1910. Here is the corresponding graph for England:

england

And for Wales:

wales

Though the same trend exists, it is not very pronounced. It is more pronounced for Northern Ireland:

northern_ireland

It is a lot more pronounced for Scotland:

scotland

Thus, it would appear that the overall increase in annual UK precipitation from 1973 is due in large measure to an increase in rainfall in Scotland, with a lesser contribution from Northern Ireland and only very minor contributions from England and Wales.

Cumbria, Lancashire and Yorkshire are of course in England and the Environment Agency is of course responsible only for flood defences in England. So pointing out that rainfall in the UK has increased significantly, when much of that increase has been in Scotland and Northern Ireland, is not that relevant, particularly when the flooding in England has provoked sharp criticism of England’s freshwater flood preparedness measures as managed (badly, it seems) by the Environment Agency. It is even more irrelevant in that even the UK annual rainfall data shows there has been no really significant increase in Winter precipitation since 1910, the issue at present being winter rainfall causing flooding.

uk1

2014 again stands out but there is very little overall increase in trend since 1910. Given the fact that winter 2015/16 still has 2 more months to go, it may or may not turn out out to be a particularly wet winter overall.

The lesson here (if there is one) is, don’t listen to BBC Radio FiveLive if you want all the facts about current severe flooding and what may be contributing to it.

 

Is December’s Rainfall in the NW ‘Unprecedented’?

Unprecedented flooding, unprecedented river levels, even – according to Liz Truss, unprecedented rainfall. I thought I would take a look at the HadUKP data to see if the hype from the politicians matches up to reality. Short answer: not really.

Firstly, let’s take a look at the December graph for England and Wales, which goes back to 1766 (2015 data is obviously not in yet as there are a few days to go).

What is obvious is that for the first 100 years after 1766, England and Wales were relatively dry for this month. Thereafter, it got quite a lot wetter in general. In 1876, the record for December rainfall was set. Since then, no December has ever been wetter. 2015 looks unlikely to beat the 1876 record of 194mm – it is 120mm as of Dec 26th.

We would need very heavy rainfall widely across England and Wales over the next few days for this record to tumble. But regardless of whether it does or not, it can be seen that, from the beginning of the 20th Century, there has been no clear upward trend in December rainfall in England and Wales. Indeed, if we look at the decade centred on 1910, we can see that this actually had the wettest run of Decembers in the entire period.

So, what about December rainfall in the North West?

Again, no overall increase discernible since about 1910. It is noticeable that from about 1907 to 1920, Decembers in this region were consistently very wet, hence the peak in the decadal average. It has been quite wet in the NW in December since 1980 – though not consistently so – and the record was set in the early 80’s, which also might be broken by this year’s very wet December. But ‘unprecedented’? Hardly. The NW records only go back to 1873. If 2015 rainfall exceeds the early 80’s record, it will only be ‘unprecedented’ within the last nearly 150 years and even then, a fairly isolated extreme occurrence.

Finally, let’s look at winter rainfall in general, firstly in the NW:

Once again, we don’t see much evidence of a definite trend throughout the last 100 years. The record wet winter for this region occurred about 1992. Will 2015 be wetter overall? Jan and Feb are yet to come. Watch this space. What about winter precipitation in England and Wales as a whole?

It’s the same story really. No clear increasing trend in winter precipitation since the very wet period centred around 1910. 2014 stands out as a clear record though, but very wet winters would have to continue for a good few years yet for meteorologists to point to a trend and then for climatologists and politicians to tell us that that trend is anthropogenic in origin.

So, the data (inconvenient as it may be) doesn’t match up to the climate change rhetoric being spouted by politicians looking for an excuse for a woeful lack of flood preparedness, plus the hype by green activists and their insistence upon bandying around their favourite term ‘unprecedented’.

Did Climate Change(TM) Cause the UK Floods Pt.2

Here we go again. Another wet UK winter, another round of attempts by politicians and activist scientists to capitalise upon winter flooding to advance their global warming agenda – in the case of politicians, to justify their need to impose swingeing taxation upon homes and businesses in the pursuit of a low carbon economy. First off the blocks, Dame Julia Slingo of the Met Office who last time (Somerset flooding in winter 2013/14) said “all the evidence points to a link with climate change”. This time, a little more caution, or should I say, a greater use of weasly words which allow for more wriggle room but which still manage to convey intact the essential message that global warming is wrecking our weather:

“It’s too early to say definitively whether climate change has made a contribution to the exceptional rainfall. . . . . However, just as with the stormy winter of two years ago, all the evidence from fundamental physics, and our understanding of our weather systems, suggests there may be a link between climate change and record-breaking winter rainfall. Last month, we published a paper showing that for the same weather pattern, an extended period of extreme UK winter rainfall is now seven times more likely than in a world without human emissions of greenhouse gases.”

Cue Liz Truss, our Environment Secretary un-extraordinaire, who then joined the party by claiming that the pattern of winter flooding was what could be expected due to climate change. The Times Environment Editor Ben Webster begged to differ, as did Christopher Booker, among others. The point is, what caused the floods was our weather, and what drives our weather during such wet winter periods is depressions crossing/forming in the Atlantic, guided by the Jet Stream. To glibly state that ‘fundamental physics’ suggests there may be a link between heavy rainfall in winter and global warming is ridiculous; it’s just more global warming propaganda from the Met Office Chief Scientist. There are a huge variety of factors at play in determining the weather of the British Isles and the changing patterns of that weather and if you want to get to the root of what may be the emergence of a new pattern, you have to examine those factors in detail.

What is virtually certain is that neither the Somerset flooding nor this year’s Cumbrian floods are in any way ‘unprecedented’. They are notable, they are unusual in the context of ‘recent’ weather; taken in combination with just two years separating them, they may even be suggestive of a change in the pattern of winter weather over the British Isles, be it temporary or more long term. Certainly, the rain which Storm Desmond dumped on Yorkshire, causing the waterfall over Malham Cove to flow for the first time in what may be hundreds of years, is a precipitation event worthy of note. But of course, what this means is that, long before cars, buses, planes and trains – and coal-fired power stations – were emitting vast amounts of fossil fuel CO2 into the atmosphere, it was raining just as heavily oop north as it is now. And England was probably cooler on average then, if the Central England temperature record is anything to go by. Which brings me to an interesting post by Paul Homewood.

We see from this that Lamb identified a period of increased storminess and elevated precipitation in Northern Europe at the close of the Medieval Warm Period and the beginning of the Little Ice Age. Indeed, Paul Homewood has another enlightening post which points to increased storminess actually during the Little Ice Age. It would appear to be the case that an enhanced temperature difference between mid-latitude air and much colder Arctic air during the LIA was the engine that energised sections of the Jet Stream causing more storms over the British Isles, in combination perhaps with a more southerly tracking (meridional – ‘looping’ as opposed to zonal – more straight) Jet Stream at that time. This is exactly the type of pattern that appears to be happening now and, in addition to causing very wet, mild, stormy winters, has also given us a notably very cold winter during 2009/10, the 2nd coldest December since 1659 in 2010 and the very cold Spring of 2013. So over the last 6 years, it hasn’t all been wet and mild as far as winters go.

England has been cooling on average since about 2005 according to the CET record. The record warm year of 2014 has reversed that trend a little, but not erased it and even with the warm winter we have so far had, 2015 is looking unremarkable. Meanwhile, despite a very strong El Nino, the Pause in global warming continues at least in the two satellite datasets, the Arctic this winter continues to gain ice at a record rate, whilst Greenland remains decidedly frigid and the North Atlantic ‘cold blob’ actually grows. Growing Arctic sea ice and a colder Atlantic are indicative of the slowing in AMOC [Atlantic Meridional Overturning Circulation] and the downturn in AMO [Atlantic Multidecadal Oscillation], having recently peaked. These two major oceanic/climate indices, of course, are intimately linked.

With solar activity predicted to decline further in SC25, it is entirely feasible that the Northern Hemisphere at least may see a period of sustained cooling, especially if, as seems increasingly more probable, the actual transient climate response to CO2 is less than that which emerges from the climate model runs of CMIP5. With all this in mind, I am persuaded towards the heretical viewpoint that the climate of the British Isles is changing, but not because of CO2; rather, we are headed for a cooler, more turbulent period due to natural variability – entirely in keeping with past variations in the British climate. Who knows, by 2100 we may be growing grapes on Tyneside, but I personally doubt that!

 

Walker Lecture – Sir David King Warns of Coming European Heatwaves Using Graph Ending 2003

Ed Hawkins tweeted about Sir David King’s talk at the University of Reading Walker Lecture yesterday. David King, if you are unaware is the UK’s Special Representative for Climate Change, appointed by the Foreign Secretary in September 2013. He was previously the Government’s Chief Scientific Adviser (2000-2007), advocating action on climate change (global warming as it then was) during his tenure. Here is the graph he was presenting to back up his argument that we should expect, by 2050, heatwaves of the type that hit Europe in 2003, to be the norm – under current GHG emissions scenarios. I questioned Ed Hawkins about the graph as the axes were not very informative and there was no title. Ed kindly informed me that the graph showed modelled Central European temperatures 1900-2100 vs. observed (black), ending in 2003. So why show observations only up to 2003? The peak is very obvious – 2003 was, by all accounts, a phenomenally hot summer in Europe. European summers since have been nowhere near as hot – often fairly cool – hence the suspicion is that later observations were simply left off of the graph because they did not match the projected rapid rise in summer temperatures. I cannot say for sure whether this is the case but I can say that temperatures in Germany (a fair proxy of Central Europe) have failed to live up to the climate model expectations in recent years. First, let’s look at a graph of average German summer temperatures 1997-2012: As you can see, 2003 stands out clearly, but the 8 years after show a decline in summer temperatures. 8 years of course, is too short a period to judge for sure whether summer temperatures are declining in Germany but the linear trend since 1997 is only very slightly positive and the polynomial fit shows a rise and decline. 2012 and 2014 were average and slightly above average summers in Germany with just 2013 standing out as significantly warmer than the long term average: June, July & August.

On a further note, it woud appear that early Spring and Winter temperatures have actually been significantly declining in Germany since 1998.

So even though King’s graph looks impressive, appearing to match observations with models very accurately, all is not quite as it seems. The hindcast data has very likely been ‘tuned’ to match observations, notwithstanding the fact that pre 1950 temperature reconstructions have hypothesised anthopogenic GHG forcing largely absent, therefore they are, in effect, modeling mainly natural variability, and – perhaps unsurprisingly – seem to do a fairly good job. It’s when the models predict increasing global temperatures under ever greater GHG forcing that they seem to run into trouble, with projected temperatures seen to be increasingly divergent from reality. As can be seen from King’s graph, temperatures in Central Europe rose rapidly from 1900 to about 1950, cooled to 1975/80, then rose rapidly again – at what looks to be approximately the same rate as the pre-1950 warming. The post 2003 data is highly likely to be flat/very slightly increasing or even declining – unlike the modeled increase. It is this modeled increase in mean summer temperatures which allows King to claim that the damaging 2003 heatwave in Europe will be ‘normal’ by 2050 – unless, of course, we drastically curb emissions. To my mind, this is not science, it is political posturing ahead of Cop21 in Paris 2015

Much alarmist ado about AMOC and the subpolar gyre collapsing

Tallbloke's Talkshop

There seems to be a buzz in the alarmosphere about the gulf stream stopping because emissions. I must admit I don’t have much time to spare at the moment for dealing with the ramped up rhetoric about ‘man made climate change’, but I spotted a typical tweet from Professor Ray Wills which I thought was worth a quick reply.

This is of course, nonsense.

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