Recent climate research in the news

A research paper published in Nature Geoscience (Otto et al, 2013) led to a fair amount of media coverage yesterday, including articles in the Guardian, BBC and an opinion piece by Matt Ridley in The Times (this article is behind a pay wall).

The research paper looked at a ‘best estimate’ of the warming expected when the concentration of carbon in the atmosphere is doubled over pre-industrial levels (known as the Transient Climate Response).

Alexander Otto, Research Fellow in Climate Decisions at the Environmental Change Institute, University of Oxford, was the lead author of the research.

He has written an article discussing the science and the implications of the research which can be seen on the Research News pages on our website.

Here is a short extract from Alexander Otto’s article :

“We published a paper in Nature Geoscience on Sunday giving a new best-estimate of 1.3°C for the Transient Climate Response, or the warming expected at the time carbon dioxide reaches double its pre-industrial concentration, using data from the most recent climate observations.

This best-estimate is lower than the HadGEM2 [one of the Met Office climate models] TCR value of 2.5°C and it is also 30% lower than the multi-model average of 1.8°C of the CMIP5 models used in the current IPCC assessment. Does this mean that the Met Office’s advice to government is based on a flawed model? Certainly not.

It is well acknowledged by all that the HadGEM2 model is at the top end of the range of TCR values in CMIP5, but we need a diverse range of TCR values to represent the uncertainties in our understanding of climate system processes. And the Met Office’s advice to government, like any solid policy advice, is based on the range of results from different models, not just their own.

…

The ‘warming pause’ over the recent decade does not show that climate change is not happening. And it certainly does not mean that climate scientists are “backing away” from our fundamental understanding.

Every new decade of data brings new information that helps reduce uncertainties in climate forecasts. In some ways, the picture changes surprisingly slowly for such an intensely scrutinised problem… This study highlights the importance of continued careful monitoring of the climate system, and also the dangers of over-interpreting any single decade’s worth of data.”

March is joint second coldest on record

Provisional full-month Met Office figures for March confirm it has been an exceptionally cold month, with a UK mean temperature of 2.2 °C.

This is 3.3 °C below the 1981-2010 long-term average for the month, and ranks this March as joint second coldest (with 1947) in our records dating back to 1910. Only March 1962 was colder, with a record-breaking month mean temperature of 1.9 °C.

In an unusual turn of events, this March was also colder than the preceding winter months of December (3.8 °C), January (3.3 °C) and February (2.8 °C). This last happened in 1975.

Looking at individual countries, the mean temperature for England for March was 2.6 °C – making it the second coldest on record, with only 1962 being colder (2.3 °C). In Wales, the mean temperature was 2.4 °C which also ranks it as the second coldest recorded – with only 1962 registering a lower temperature (2.1 °C). Scotland saw a mean temperature of 1.3 °C, which is joint fifth alongside 1916 and 1958. The coldest March on record for Scotland was set in 1947 (0.2 °C). For Northern Ireland, this March saw a mean temperature of 2.8 °C, which is joint second alongside 1919, 1937, and 1962. The record was set in 1947 (2.5 °C).

This March was also much drier than average for the UK, with 62.1mm of rain falling during the month – just 65% of the 95.1mm average. Scotland was particularly dry, seeing 49.5mm of rain which is 35% of its long term average for the month.

Sunshine hours were also slightly down compared to average, with 82.9 hours for the UK notching up 81% of the average.

The cold and dry conditions seen in March were largely due to high pressure dominating UK weather patterns, allowing cold and relatively dry air to move in from the east. While this pattern is set to continue through the first week of April, milder and more unsettled conditions are expected to move in for the start of next week. You can stay up to date with the latest information with the Met Office’s forecasts.

March 2013	Actual	Difference from average	Actual	% of average
Regions	°C	°C	mm	%
UK	2.2	-3.3	62.1	65
England	2.6	-3.6	64.4	101
Wales	2.4	-3.4	86.2	74
Scotland	1.3	-2.9	49.5	35
N Ireland	2.8	-3.1	74.1	78
England & Wales	2.6	-3.6	67.4	95
England N	1.8	-3.7	56.4	75
England S	3	-3.5	68.6	118

March – top five coldest in the UK

1	1962	1.9 °C
2	2013	2.2 °C
2	1947	2.2 °C
4	1937	2.4 °C
5	1916	2.5 °C

Fascination and forecasting – guest blog by Siân Lloyd

Siân Lloyd

Here in the UK we’re famous for being obsessed with the weather, and I’m no exception to that. My fascination with the weather started from a young age because my father had a passion for the outdoors, so we were always out in all weathers.

Coming from Wales, where we get continually walloped by fronts spinning off the Atlantic, you certainly see a great variety of weather and you soon get used to coping with whatever gets thrown at you. I remember eating egg and marmite sandwiches on Gower beaches, sat in a kagool with my father saying the rain would clear soon – he was always an optimist.

It’s not just my own experiences that captured my fascination, but also the myths and legends of the Celtic landscape I grew up in. Virtually every story has weather in it – from violent storms, to great floods, or the tranquil calm of a summer’s day. So for me, weather represents the drama of life and is the very stuff of our literature.

So it doesn’t surprise me that, wherever I go, people are always keen to talk about the weather and what’s in the forecast. I know I may be biased, but I really do believe that forecasting is hugely important. From protecting people from the harshest conditions our climate has to offer, to helping fashion conscious ladies like myself decide what to wear, forecasts help us in so many aspects of our day to day lives.

In many ways we take forecasting for granted, but to me the ability to predict the weather days ahead is a true feat of human ingenuity and one of the great triumphs of science. In 1922, mathematician Lewis Fry Richardson estimated you’d need 64,000 people doing endless calculations to get a forecast in time to make it useful – looking just a few hours ahead. Today we take observations from all over the world, from the top of the atmosphere to the depths of the oceans, put them in a supercomputer that does trillions of calculations a second to make forecasts, then people like me interpret that output to put together tailored forecasts which can be transmitted around the world in seconds. Truly amazing stuff.

I’ve been in weather forecasting for 20 years and things have changed a lot. One of the biggest changes is the huge strides in accuracy that have been made. Even from my personal experience I can tell how much better forecasts are and the statistics bear that out. The Met Office’s four-day forecasts are as accurate as its one day forecasts were 30 years ago, and things are still improving all the time as we understand more about the way the atmosphere works and technology improves.

The other big thing that I’ve noticed is that the weather used to follow the news, but now it very often is the news. So often these days I get asked to speak on air during bulletins about floods or droughts and why we’re seeing them. So, from my personal experience, it seems like the weather is changing and that our warming climate is playing a part. As we go forward then, science once again will have an important role to play in helping us understand how and why things are changing, and ever more accurate forecasting will help keep everyone prepared for whatever the weather has in store.

If you want to learn more about our weather and climate, as well as how it all works, you can read about it in ‘An Essential Guide to the Weather’ – a two part guide which will be free in The Telegraph this weekend on the 9^th and 10^th of March. Part 1, in Saturday’s paper, explains the causes of our weather and provides a comprehensive guide to clouds and other types of weather. Part 2 looks at how weather forecasting is done, extreme weather, and climate zones around the world.

Top ten: Mildest temperatures recorded last night

Yesterday was a mild day with temperatures reaching as high as 19.2 °C, which was recorded in Langdon Bay during the daytime. However night-time temperatures were also mild for the time of year, with many areas not dropping below 10 °C. Jersey was particularly warm, not falling below 13.5 °C last night.

Station	Temperature (°C)
Jersey: Airport	13.5
Bognor Regis	12.9
Guernsey: Airport	12.9
Langdon Bay	12.1
Manston	12.1
Frittenden	11.9
Herstmonceux, West End	11.9
Faversham	11.8
Scilly: St Marys Airport	11.7
Skegness	11.7

Overnight lows at this time of year would typically be around 7 to 9 °C across southern England, making last night around 4 or 5 °C milder than average. More UK climate and weather statistics are available on our website.

Met Office in the Media: 14 October 2012

An article by David Rose appears today in the Mail on Sunday under the title: ‘Global warming stopped 16 years ago, reveals Met Office report quietly released… and here is the chart to prove it’

It is the second article Mr Rose has written which contains some misleading information, after he wrote an article earlier this year on the same theme – you see our response to that one here.

To address some of the points in the article published today:

Firstly, the Met Office has not issued a report on this issue. We can only assume the article is referring to the completion of work to update the HadCRUT4 global temperature dataset compiled by ourselves and the University of East Anglia’s Climate Research Unit.

We announced that this work was going on in March and it was finished this week. You can see the HadCRUT4 website here.

Secondly, Mr Rose says the Met Office made no comment about its decadal climate predictions. This is because he did not ask us to make a comment about them.

You can see our full response to all of the questions Mr Rose did ask us below:

Hi David,

Here’s a response to your questions. I’ve kept them as concise as possible but the issues you raise require considerable explanation.

Q.1 “First, please confirm that they do indeed reveal no warming trend since 1997.”

The linear trend from August 1997 (in the middle of an exceptionally strong El Nino) to August 2012 (coming at the tail end of a double-dip La Nina) is about 0.03°C/decade, amounting to a temperature increase of 0.05°C over that period, but equally we could calculate the linear trend from 1999, during the subsequent La Nina, and show a more substantial warming.

As we’ve stressed before, choosing a starting or end point on short-term scales can be very misleading. Climate change can only be detected from multi-decadal timescales due to the inherent variability in the climate system. If you use a longer period from HadCRUT4 the trend looks very different. For example, 1979 to 2011 shows 0.16°C/decade (or 0.15°C/decade in the NCDC dataset, 0.16°C/decade in GISS). Looking at successive decades over this period, each decade was warmer than the previous – so the 1990s were warmer than the 1980s, and the 2000s were warmer than both. Eight of the top ten warmest years have occurred in the last decade.

Over the last 140 years global surface temperatures have risen by about 0.8ºC. However, within this record there have been several periods lasting a decade or more during which temperatures have risen very slowly or cooled. The current period of reduced warming is not unprecedented and 15 year long periods are not unusual.

Q.2 “Second, tell me what this says about the models used by the IPCC and others which have predicted a rise of 0.2 degrees celsius per decade for the 21st century. I accept that there will always be periods when a rising gradient may be interrupted. But this flat period has now gone on for about the same time as the 1980 – 1996 warming.”

The models exhibit large variations in the rate of warming from year to year and over a decade, owing to climate variations such as ENSO, the Atlantic Multi-Decadal Oscillation and Pacific Decadal Oscillation. So in that sense, such a period is not unexpected. It is not uncommon in the simulations for these periods to last up to 15 years, but longer periods are unlikely.

Q.3 “Finally, do these data suggest that factors other than CO2 – such as multi-decadal oceanic cycles – may exert a greater influence on climate than previously realised?”

We have limited observations on multi-decadal oceanic cycles but we have known for some time that they may act to slow down or accelerate the observed warming trend. In addition, we also know that changes in the surface temperature occur not just due to internal variability, but are also influenced by “external forcings”, such as changes in solar activity, volcanic eruptions or aerosol emissions. Combined, several of these factors could account for some or all of the reduced warming trend seen over the last decade – but this is an area of ongoing research.

———–

The below graph which shows years ranked in order of global temperature was not included in the response to Mr Rose, but is useful in this context as it illustrates the point made above that eight of the warmest years on record have occurred in the past decade.

Graph showing years ranked in order of global temperature.

Met Office confirms wettest June in over a century

Provisional Met Office figures for June show double the average amount of rain has fallen, making it the wettest June since records began in 1910.

This is the second record breaking month of rainfall this year, with April also topping the rankings. The period from April to June is also the wettest recorded for the UK.

It is also the second dullest June on record with just 119.2 hours of sunshine, narrowly missing out on the record of 115.4 hours set in 1987. To complete the disappointing picture, it has also been the coolest June since 1991 with a mean temperature of 12.3 deg C.

Unsettled weather has never been from the UK during the past three months, with only the latter half of May seeing a spell of prolonged fine weather.

Movements in the track of the jet stream, a narrow band of fast flowing westerly winds high in the atmosphere, have contributed to the weather we have seen.

This June has seen periods of heavy and prolonged rain, as well as short but exceptionally heavy showers.

The total UK rainfall was 145.3mm – exactly twice as much as you would normally expect compared to the 1971-2000 average. This beats the previous record of 136.2 mm set in 2007.

Looking at individual countries, it has been the wettest June on record for Wales and Northern Ireland, the second wettest in England, and the eighth wettest in Scotland.

Many areas have seen extremely high rainfall – with 83 (out of 237) observation sites marking their wettest June on record. Some of these aren’t significant as they have very short recording histories, just a year in some cases, but others have been operating much longer - Otterbourne in Hampshire been operating for 119 years.

One of the key features of the month has been that the far north west of the UK, traditionally the wettest part of the country, has been remarkably dry.

Up until quite late in the month, a few stations in this area were below their record lowest rainfall amounts – but they just missed the record books with rain falling in the last few days of the month.

Met Office provisional June figures

	mean temperature		sunshine duration		rainfall
	Actual	Difference from 1971-2000 average	Actual	% of 1971-2000 average	Actual	% of 1971-2000 average
	degC	degC	hours	%	mm	%
UK	12.3	-0.3	119.2	70	145.3	200
England	13.4	-0.2	121	67	142.6	227
Wales	12.7	0	120.6	71	205	238
Scotland	10.4	-0.6	119.4	77	129.4	152
N Ireland	12	-0.4	97.4	64	169.2	235
England & Wales	13.3	-0.2	121	68	151.2	229
England N	12.5	-0.3	105.9	63	162.5	234
England S	13.9	-0.2	129	69	132.1	222

Current or previous wettest years on record are:

· UK: (Previous) 136.2 mm in 2007

· England: 146.0 mm in 2007

· Wales: (Previous) 183.1mm in 1998

· Scotland: 155.0 mm in 1938

· Northern Ireland: (Previous) 152.6 mm in 1912.

Average UK conditions (1971-2000):

· Mean temperature: 12.6 deg C

· Rainfall: 72.6mm

· Sunshine: 169.4 hours

Related articles

• Wettest June sees double rainfall (itv.com)
• June seeps into record books as wettest month (guardian.co.uk)
• UK News: Record rainfall makes June the wettest since 1910 (walesonline.co.uk)

What are climate models?

A key way of understanding our climate and making projections about how it may change in the future is to use climate models.

These are essentially simulations of the Earth’s climate system. They are made up of millions of lines of computer code which represent the physical processes which govern our atmosphere and oceans.

Supercomputers then run the code using observations of modern day climate, with the models able to recreate the past (hindcasting) or give projections of the future (forecasting).

Looking at the past is important for understanding historical changes and influences on climate, and it also allows scientists to gauge how accurate the models are (by comparing model output to reality).

Looking at the future enables researchers to see how things might change given various different scenarios – such as changing levels of greenhouse gases.

The Met Office uses models to look at many different timescales and to study different aspects of the Earth’s climate system.

You can find out more about how climate models work in our YouTube video.

 

Long to rain over us

Weather often makes front page news but today it’s the weather forecaster who has garnered the headlines – as the paper’s focus on the Prince of Wales’ star turn as a presenter.

Prince Charles and the Duchess of Cornwall both tried their hand at delivering the Met Office weather forecast on the BBC during a tour of BBC Scotland’s Glasgow headquarters yesterday.

While they couldn’t do anything about the wet, windy and rather cold weather – they certainly did an accomplished job at getting the message across.

At one point, the Prince said: “But a cold day everywhere with temperatures of just 8C and a brisk northerly wind. Thank God it isn’t a bank holiday.”

The forecast has been a big hit on the internet, as the forecast has been viewed nearly 100,000 times on YouTube.

It has also created interest around the world, as numerous National Met Services have contacted the Met Office to compliment the Prince’s forecasting skills – suggesting he might be a good new recruit!

This is not the first time the Prince has had a close-up view of the Met Office’s world leading forecast science, as he paid a visit to our Exeter HQ in 2009

As someone with a keen interest in weather and climate change, he used the visit to find out more about our cutting edge capabilities in forecasting and our pioneering climate research. Perhaps that visit was good preparation for his performance yesterday!

At the time of his visit to the Met Office Prince Charles said: “But for somebody like myself who spent at least a little bit of time in the past, when I was serving in the Royal Navy and learning to fly in the Royal Air Force, as you can imagine meteorology was quite an important part of this particular exercise.

“Having understood a little bit about what weather patterns are all about, to me it’s particularly interesting to see what you do here [at the Met Office].”

The Met Office is a leading provider of weather services for the UK’s media industries – providing forecasting solutions for the BBC, ITV, STV and UTV.

We also run TV weather presenter training so others can hone their skills before going in front of the cameras.

Why does it always rain on the UK?

After the wettest April in records dating back to 1910 and an unsettled start to May, parts of the UK are set to see more heavy rain today and tomorrow.

With all the wet weather, many people have been asking what is to blame and whether something unusual is going on.

In an earlier article on this blog we looked at how the jet stream has influenced the recent spell of unsettled weather, but stressed it is not the only factor at play.

While the jet stream may be an influence, there is nothing unusual about its current position and it regularly behaves in this way.

With that in mind, it’s possible to go a step further and say there is nothing unusual about the UK’s weather over the last few weeks.

That may sound odd on the back of a record-breaking wet month, but we do expect to see records broken and they do topple fairly regularly for one area or another.

The past April fits into this expectation – it was exceptionally wet, but only slightly wetter than the previous record set just a few years ago in 2000 and there are several years close behind.

We only have to look back another month to see that March was the joint warmest on record for Scotland. Looking further back, parts of the UK have seen some of their driest months on record in the last year or so, and we saw the coldest UK December on record in 2010.

The mixture of record-breaking months in recent history illustrates what’s called natural variability – which is a way of summing up the inherent random or chaotic nature of weather. This is why our weather is different from one week, month or year to the next.

Here in the UK that variability is particularly noticeable because of our location. We sit in the mid-latitudes where cold air from the poles meets warm air from the tropics, and have the Atlantic on one side and the large landmass of continental Europe on the other.

All these factors mean our weather can be highly variable and we can see periods of unsettled, wet and windy weather at any time of year – a challenge that the Met Office has to rise to every day to provide the accurate weather forecasts that you, businesses and our government partners have come to expect.

April 2012 early statistics – above average rainfall

These are early figures covering 1 – 25 of April and not full month statistics, so are therefore very likely to change. Especially regarding ranking. Full month figures will not be available until provisionally Wednesday 2 May.

Figures for 1 - 25 April show the month so far has seen well above average rainfall across the UK, with 97 mm of rain recorded – this is 139% of the long-term monthly average (1971-2000). The wettest April in the records dating back to 1910 was 2000 which saw 120.3 mm of rain.

Currently the month is the 9th wettest April for the UK in the records. However, it’s not possible to say where the month will end up in the records until all the figures are in at the end of the month – especially as we are expecting heavy rain on Sunday.

Some areas have seen significant rainfall amounts with some parts of the UK already having had more than double their monthly average. Some station records are also very likely to be broken.

Impact on drought

Looking at the England South area, which has been the focus of the current drought, this month is one of only three in the last two years which has seen significantly above average rainfall.

As can be seen from the chart below, the majority of other months during that time have seen below average rainfall.

Monthly rainfall anomalies for region England south for the last 3 years. 13 of the last 24 months have seen less than 75% of average rainfall, and 6 months have seen less than 50%. Only 2 months - June 2011 and August 2010, have been significantly wetter than average.

Trevor Bishop, Head of Water Resources at the Environment Agency, said: “it’s going to take more than a week or two of rain to undo the effects of nearly two years of below average rainfall.

“More rain now will really help us get through the summer, and is good for the environment, farmers and gardeners, but it’s very unlikely to be enough to recharge the groundwater.”

Duller and slightly cooler than average

Temperatures have been close to the average for the time of year, despite some cold nights towards the beginning of the month which brought frosts to many areas.

Sunshine hours have been slightly down on the average so far this month, with most parts of the country seeing only about two thirds to three quarters of the average expected in the month. However, this could improve during the final few days of April.

Why the unsettled weather this month?

The position of the jet stream has been one key contributing factor, but potentially not the only one. You can read more about this on our blog post.