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.
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.”
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 9th and 10th 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.
This article contains a series of factual inaccuracies about the Met Office and its science, as outlined below.
Firstly, he claims the Met Office failed to predict snow in 2010, but our 5-day forecasts accurately forecast 12 out of 13 snowfall events – as you can see in this article. In addition the Press Complaints Commission has also already addressed this fallacy with the Daily Telegraph in February of last year. As a result the newspaper published a clarification that highlighted that “the Met Office did warn the public of last winter’s [2010/11] cold weather from early November 2010.”
Mr Delingpole also says we failed to predict flooding in November last year. Once again, our 5-day forecasts gave accurate guidance and warnings throughout the period. In just one example of feedback the Met Office has received for highly accurate forecasting and guidance throughout 2012, Assistant Chief Constable Paul Netherton, Chair for the Local Resilience Forum for Devon, Cornwall and the Isles of Scilly (which was one of the areas most affected by flooding in November), said: “[I] would like to formally thank and recognise the hard work of the Met Office over the past week. The information you provided was invaluable and enabled the responders in Devon, Cornwall and the Isles of Scilly to prepare and respond effectively to assist our communities.”
Mr Delingpole then inaccurately states that the Met Office has conceded ‘there is no evidence that ‘global warming’ is happening’. We have not said this at any point.
In fact, we explicitly say this was not the case in an article, posted on the home page of our website and widely circulated, which was written in response to articles about updates to our decadal forecast. Professor Julia Slingo, Met Office Chief Scientist, has also provided a more in depth feature on ‘Decadal Forecasting – What is it and what does it tell us?’.
Further on in the print version of the article (although amended online), Mr Delingpole says “According to the Met, Britain is apparently experiencing more rain by volume and intensity than at any time since records began.” Although he is right in saying the Met Office has published preliminary observations which show an increase in the intensity and volume of rain, we are clear that this relates to a period from 1960 onwards – not ‘since records began’ as he claims.
He also states that the Met Office was trying to defend a narrative that the “the past ten years have been the ‘wettest decade ever’”. Again, this is not something the Met Office has ever said.
Also he quotes David Whitehouse of the Global Warming Policy Foundation saying that the Met Office ‘thinks weather forecasting is beneath it’ and that ‘climate change… brings in more money’.
A cursory glance at our annual report and accounts (pdf) would reveal weather forecasting represents the vast majority of the Met Office’s contractual work on behalf of the public.
There are also a number of other accusations which cannot be substantiated.
Mr Delingpole does quote Dr Whitehouse saying “when it comes to four or five day weather forecasting, the Met Office is the best in the world.”
This supports the view of the World Meterological Organization (WMO) which consistently ranks the Met Office in the top two operational forecasters in the world.
Our reputation for forecasting accuracy is based on our commitment to provide the world’s best weather and climate service which helps protect lives and property here in the UK and around the world.
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.
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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.
In fact, barring a warm and dry spell towards the end of May, the weather has been persistently dull and wet since April – which was also the wettest in records dating back to 1910.
Our weather here in the UK is complex and determined by many different factors, including the position of the jet stream.
This is the narrow band of fast moving winds which runs from west to east across the Atlantic high up in the atmosphere.
How does the jet stream affect UK weather?
Weather (or low pressure) systems bearing rain and unsettled conditions move across the Atlantic on a regular basis. The jet stream guides these systems, so its position is important for UK weather.
In summer, we would expect the jet stream to be north of the UK – dragging those weather systems away from our shores to give us relatively settled weather.
So far this year it has been to the south of the UK, guiding those systems straight to us. This is the position we’d normally expect the jet stream to be in during winter, when we are more accustomed to these wet conditions.
So why is the jet stream stuck so far south?
The jet stream, like our weather, is subject to natural variability – that is the random nature of our weather which means it is different from week, month or year to the next.
We expect it to move around and it has moved to the south of the UK in summertime many times before in the past. It has, however, been particularly persistent in holding that position this year – hence the prolonged unsettled weather.
This could be due to natural variability – a bad run of coincidence, if you will – but climate scientists are conducting ongoing research to see if there are other factors at play.
Changes in sea surface temperatures due to natural cycles may be playing a part, but there is more research to be done before anyone can establish how big a role they play.
Research has also suggested that reducing amounts of Arctic sea-ice could be affecting weather patterns, but more research needs to be done to confirm this link. Currently Arctic sea-ice is at a record low for this time of year.
Is climate change playing a role?
In the long term, most climate models project drier UK summers – but it is possible there could be other influences of a changing climate which could override that signal on shorter timescales.
If low levels of Arctic sea ice were found to be affecting the track of the jet stream, for example, this could be seen as linked to the warming of our climate – but this is currently an unknown.
However, it is very difficult to do this type of analysis with such highly variable rainfall events, so it may take many years before we could confirm how the odds of this summer’s wet weather happening have been altered by greenhouse gases.
We do know that the warmer air is, the more moisture it can hold. We have seen a global temperature increase of more than 0.7 deg C (since pre-industrial times) and this has led to an increase of about 4-5% in atmospheric moisture.
This means that when we do get unusual weather patterns such as we’re seeing now, it’s likely there will be more rainfall than the same patterns might have produced in the past. In short, it seems when it does rain, it is heavier.
Taking into account this effect, perhaps it’s not surprising new records like those for this April and June are being set. In fact, the wettest July and November in the records dating back to 1910 happened in 2009, making a total of four record wettest months in the past four years. If wet months occurred randomly, we would expect only one record to have been broken since 2006.
For temperature, April (2011), May (2008), July (2006), September (2006) are all recent warmest records. Again, this is much more frequent than would be expected if temperatures were not rising.
What about elsewhere in the world?
Looking at the bigger picture, the jet stream may be having an impact elsewhere in the northern hemisphere.
It is stuck in a persistent pattern of waves, with one of these ‘waves’ taking it to the south of the UK.
Figure shows upper level wind patterns in early July 2012, with the northern hemisphere jet stream marked with arrows.
The figure gives a picture of the upper level winds for the first week in July, but the wavy nature of the jet stream has been persistent throughout June.
Meanders of the jet north and south can be seen across the US, the Atlantic and into Europe.
While the wet weather in the UK has been under a southward meander of the jet stream, the recent Russian floods near the Black Sea appear to have been beneath the next trough to the east.
The US heat wave is also beneath a northward meander and a ridge of high pressure.
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.
BBC Horizon will broadcast ‘Global Weirding’ on BBC Two tonight at 9pm, exploring the science behind why the world’s weather seems to be getting more extreme and if these patterns are a taste of what is to come.
Horizon say: “Something weird seems to be happening to our weather – it appears to be getting more extreme. In the past few years we have shivered through two record-breaking cold winters and parts of the country have experienced intense droughts and torrential floods. It is a pattern that appears to be playing out across the globe. Hurricane chasers are recording bigger storms and in Texas, record-breaking rain has been followed by record-breaking drought.
“Horizon follows the scientists who are trying to understand what’s been happening to our weather and investigates if these extremes are a taste of what’s to come.”
The producers of the programme visited the Met Office headquarters and Operations Centre in Exeter to film for the programme at the end of last year, interviewing Adam Scaife, Head of Monthly to Decadal Forecasting and Helen Chivers, a Met Office Forecaster. In the programme we discuss the science being undertaken here at the Met Office into the effects of Climate Change on ourt weather including the effects of Arctic sea ice depletion on European winter weather, and our role in forecasting extreme weather for the UK.
Adam Scaife and Helen Chivers from the Met Office appear in the programme
Other contributors to the programme include Mike Lockwood (University of Reading) on solar observations, Kerry Emmanuel (MIT) on hurricanes and Katharine Hayhoe (Texas Tech University) on extreme wet and dry conditions in Texas.
This weeks Radio Times also previewed the programme saying:
“This week’s Very Big Number from Horizon: the Met Office’s computer can do one hundred trillion calculations — a second. It needs to, in order to process the gouts of data gathered from satellites, data which means, we’re told, that a five-day forecast today is as accurate as a one-day forecast was 30 years ago. (Were we so long-suffering in 1982?)
“All this technology isn’t to feed some quaint British obsession with weather, it’s to keep track of increasingly freakish extremes in meteorology, not just here but around the world: from record rains in Scotland to droughts in Texas and a boom in hurricanes. Scientists are trying to get to grips with it all and Horizon follows them, in one amazing scene, right into the heart of the storm.”
A project running almost 10,000 climate simulations on volunteers’ home computers has found that a global warming of 3 degrees Celsius by 2050 is ‘equally plausible’ as a rise of 1.4 degrees.
The study addresses some of the uncertainties that previous forecasts, using simpler models or only a few dozen simulations, may have over-looked.
Importantly, the forecast range is derived from using a complex Met Office model that accurately reproduces observed temperature changes over the last 50 years.
The results suggest that the world is very likely to cross the ’2 degrees barrier’ at some point this century if emissions continue unabated.
It also suggests that those planning for the impacts of climate change need to consider the possibility of warming of up to 3 degrees (above the 1961-1990 average) by 2050, even on a mid-range emission scenario. This is a faster rate of warming than most other models predict.
The research was made possible because volunteers donated time to run the simulations on their home computers through climateprediction.net as part of the BBC Climate Change Experiment. A report of the research is published in Nature Geoscience.
“It’s only by running such a large number of simulations – with model versions deliberately chosen to display a range of behaviour – that you can get a handle on the uncertainty present in a complex system such as our climate,” said Dr Dan Rowlands of Oxford University’s Department of Physics, lead author of the paper. “Our work was only possible because thousands of people donated their home computer time to run these simulations.”
Dr Ben Booth, Senior Climate Scientist at the Met Office Hadley Centre, an author of the paper, said: “There have been substantial efforts within the international community to quantify and understand the consequence of climate uncertainties for future projections. Perhaps the most ambitious effort to date, this work illustrates how the citizen science movement is making an important contribution to this field.”
The model used in the project was supplied by the Met Office and the work was supported by the Natural Environment Research Council (NERC), the European Union FP6 WATCH and ENSEMBLES projects, the Oxford Martin School, the Smith School of Enterprise and the Environment, and Microsoft Research.
The World Meteorological Organization (WMO) and the worldwide meteorological community celebrate World Meteorological Day on 23 March. This year the theme is “Powering our future with weather, climate and water”.
World Meteorological Day 2012 - Powering our future with weather, climate and water
As a world leader in weather, climate and science, the Met Office delivers various products and services to the UK and across the globe, supporting the general public, government and local authorities, the armed forces, civil aviation, media, transport, utilities and most of the industry sector.
From the collection of data around the world, to its processing and analysis, the Met Office provides bespoke weather and climate predictions for specialist customers, and adds value to forecasts for commercial, defence and aviation customers.
Similarly, climate monitoring enables the Met Office to examine and interpret climate variations and change. This is done throughout the atmosphere, oceans and the cryosphere (ice), which enable us to develop predictions of our future climate change. This means that we can plan ahead and explore the impacts of climate change on Earth and human systems such as; water resources, agriculture, ecosystems, health and energy.
From heatwaves to periods of extreme rainfall, the weather can have a significant impact on the water industry. The Met Office is able to forecast the demand for water in a particular area based on this relationship. By working with the Environment Agency and the Flood Forecasting Centre, we have been able to produce a more in-depth knowledge of how different parts of the United Kingdom respond to rainfall, whether it is a fast responding urban catchment or a low-lying rural location with a greater capability to store water.
Weather, climate and water have moulded, shaped and changed our world in the past and it is more important than ever to look forward and understand how they might change things in the future.
Tyrone Dunbar, is a Met Office scientist currently seconded to Defra and DECC in support of our role in providing policy relevant science to Government. In this guest blog he talks about Climate Week.
This week is Climate Week, and there are thousands of climate week related events happening all over the UK. I’ve just had a quick look at the website and there are 2802 registered events shown on their interactive map, so there’s absolutely loads of stuff going on (I’ll be honest, I was surprised how many events have been organised!).
The week officially kicked off on Sunday with a launch event at Lancaster House in London. There was a wide range of inspiring projects on display, from innovative projects such as drought-resistant maize which helps farmers in Africa adapt to climate change, to campaigns such as the Sustainable Restaurant Association’s Too Good to Waste “doggy box” promotion. There was also the fantastic news that Defra and HR Wallingford won the award for Best Initiative by a Government or Statutory Body for their work on the Climate Change Risk Assessment (CCRA). The Met Office were also involved in the CCRA, providing scientific guidance on the latest climate projections (UKCP09) that underpin the study, leading on the risk assessment for the Energy Sector and provided further research on urban heat islands and rainfall runoff.
The Met Office is the official science advisor for Climate Week and we have a number of things going on as well. There was a Met Office stand at the launch event, and we have a poster display in the atrium at the Department for International Development (DfID) running throughout the week highlighting various climate change issues as well as Met Office research, such as forecasting of the onset of the rainy season in East Africa. This has been really well received and DfID will be sending this exhibition to posts around the world. We are also running a Climate Challenge competition in some local Tesco stores in Devon (Tesco are the main Climate Week sponsors), as you can see in the picture below.
You can find out more about the role of the Met Office as one of the worlds leading centres for climate science research in the climate change section of our website.
This is the official blog of the Met Office news team, intended to provide journalists and bloggers with the latest weather, climate science and business news and information from the Met Office.
The blog will post latest news releases and related content, news diary and information supporting news stories already in the media.
@kadgergoogoo Only have the 5-day for world forecasts, Looking sunny, dry and hot in the next 5 days with a little light rain on Monday. ^JS 8 hours ago
