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Fellows of the Royal Society are human too

By Jonathan Gregory

In early May I was surprised and honoured, as well as happy, to be elected a Fellow of the Royal Society. One of the best consequences of this so far has been that I was allowed the opportunity to give a speech to members of the department one afternoon at an informal celebration. Actually I had requested this occasion, following the admirable departmental tradition of celebrating successful PhD vivas etc., because I wanted to share with my colleagues some thoughts, which I’m writing down here in case they’re useful to others as well. First among these was to thank those who proposed me for the fellowship, and my bosses of the last 28 years, who recruited me into excellent research institutions and gave me the freedom to work on subjects which seemed useful and interesting to me.

It turns out that FRSs are human too. Nothing has magically changed since my election. There are still lots of things I can’t understand. I’m still worried that I won’t be able to think of enough good ideas. I still feel near to despair about the large number of things I want or need to do at work, and my inadequacy in tackling them. In fact for much of my adult life I have suffered from recurrent depression. Many of the thoughts that cause me difficulties are sometimes described as symptoms of imposter syndrome, which is a fear that you are in a position that you don’t deserve to have reached, and that any moment you might be unmasked as a fraud who has misled people into thinking that you are actually quite clever.

It is probable that some colleagues have similar fears, and it’s good to know you’re not alone. Most people need encouragement, I guess. I value my election as FRS because it’s an external recognition of climate science and the value of my contribution to it, and I’ll try to use this knowledge to help myself when I’m feeling depressed. It’s useful to remind yourself in those circumstances of positive things that others have said, and in fact I’ve compiled a list of them, to look at when in need. Because I know that positive remarks are useful to me, I advocate that we should all offer positive comments to our colleagues, staff and bosses whenever we think they’ve done something good. Positive feedback should not be lagged!

One of my jobs is to make such comments myself. My other important function is to ask questions that I feel stupid in asking, especially in group meetings etc. where there might be others who’d rather like to know the answers too but don’t feel confident to ask. It’s easier for a professor to do this job than a new PhD student, because (presuming that I am actually not altogether an imposter) I can have some confidence that I am not being unusually stupid if I don’t understand something. Actually ignorance is not the same as stupidity anyway. Ignorance is not necessarily a bad thing. Socrates said that he knew nothing except that he knew nothing, and in Nineteen Eighty-Four one of the ruling party’s slogans is “Ignorance is strength.” Maybe that’s going too far, but ignorance can certainly be useful, because it avoids preconceptions. Asking questions when you feel that the answer ought to be obvious, but doesn’t seem to be, can be a way to change people’s thinking. In his book, The structure of scientific revolutions, in which he put forward the idea of paradigm shifts, Thomas Kuhn points out that radical progress is often made by people who are new to a subject, presumably for this reason.

If people seem blank when you explain something to them, it might just be because you haven’t been clear enough, but on the other hand it could be because the subject you are dealing with is not yet properly appreciated, and you’re speaking a new language. If a subject seems unclear and confused to you, it might be because no-one properly understands it, and everyone’s been skirting round it, thinking it’s someone else’s business. So perhaps it would be a good idea to head straight in that direction and see what there is to be discovered, because there may be unknown mountains hidden in the mists of ignorance, and amazing panoramas can occasionally be glimpsed through the gaps.

The new International Cloud Atlas

By Stephen Burt

Automatic weather stations (AWS) are increasingly commonplace in meteorological reporting systems: today more than half of all surface observations come from sites that are partly or fully automated. AWS have many advantages, particularly in remote sites, or providing observations outside of normal working hours (for instance, almost all UK night-time synoptic observations are now made by AWSs). Despite advances in computer technology and image recognition systems, however, automatic observations of cloud amount and types are still pretty much hopeless, and are best left to manual observing sites. So how do we ensure global consistency in cloud reporting? Is cumulus humilis reported in the observation from Shanghai the same type of cloud reported from Los Angeles International Airport?

While cumulus, stratus and cirrus are very easy to distinguish, how are observers trained to tell the difference between cumulus fractus, cumulus humilis, cumulus mediocris and cumulus congestus? The differences are very important – one can be a sign of fair weather and very limited convective activity, another in this series denotes deeply unstable conditions, with showers or thunderstorms likely within the next hour or two. Of course, the answer has to be some kind of visual reference aid for observers – and the latest WMO version of the International Cloud Atlas has just been published on the web. It includes hundreds of photographs of clouds and related phenomena in full colour, including for the first time entries for lightning, contrails, rainbows, solar haloes, rime ice and noctilucent clouds.

The first published classification of clouds only dates back to the beginning of the 19th century and was the work of Lamarck (1802). This celebrated French naturalist did not set out to classify all possible clouds; he confined himself to distinguishing certain forms which seemed to him to be the manifestation of general causes which it would be useful to recognize. But this work, in spite of its real value, did not make any impression even in France and his nomenclature does not seem to have been used by anyone. Perhaps this was due to his choice of somewhat peculiar French names which would not readily be adopted in other countries or perhaps the paper was discredited through appearing in the same publication (Annuaire Meteorologique), as forecasts based upon astrological data.

The real breakthrough came about later that same year, when London chemist and amateur meteorologist Luke Howard published a cloud classification entirely independently of Lamarck’s which remains very largely the one we use today. Whereas Lamarck contented himself with defining and naming a certain number of interesting forms, Howard set out to establish a complete classification covering all possible cases and, importantly, began to suggest the physical mechanisms behind their formation – heap clouds (cumulus), layer clouds (stratus), and fibrous (ice) clouds (cirrus). From these three basic types, all others were derived by transition or association. His original paper On the modification of clouds was published early in 1803, and influenced artists (John Constable owned a copy), poets (Goethe was a great admirer) and the general public as well as the embryonic science of meteorology; it included exquisite watercolours of each of his main cloud types. His original artwork is held in the Science Museum on behalf of the Royal Meteorological Society.

The first photographic Cloud Atlas was published in 1896. It was based upon the work of a Swede (Hildebrand Hildebrandsson) and a titled English aristocrat, the Hon. Ralph Abercromby, who published a classification of clouds reconciling existing customs and including later acquisitions, such as altocumulus, altostratus and cumulonimbus. The super-rich Abercromby had previously made two journeys round the world in order to assure himself that the cloud forms were the same in all parts – well, that was his excuse, anyway, and why not indeed? One of the principal characteristics of this classification was the importance attached to height as a criterion, and they grouped the clouds in four levels, the mean heights of which they fixed provisionally from measurements made in Sweden (of course, this was long before radiosondes and aircraft measurements). The International Meteorological Conference, held at Munich in 1891, expressly recommended these authors’ classification and gave its sanction to the appointment of a special committee entrusted with its final consideration and publication with illustrations in atlas form. This committee met at Uppsala in August 1894 and proceeded to choose the illustrations to be reproduced. With this object in view, an exhibition of more than three hundred cloud photographs or sketches had been arranged (remember photography was still a fairly specialised and expensive occupation, and of course monochrome only). The publication commission, consisting of Hildebrandsson, Riggenbach and Teisserenc de Bort, had to contend with great technical and more particularly financial difficulties. In the end, Teisserenc de Bort took upon himself the sole responsibility for the production of the atlas. This work contained 28 hand-coloured plates accompanied by a text in three languages (French, German, English) giving definitions and descriptions of the clouds together with instructions on how to observe them. This first International Cloud Atlas constituted a great advance by making cloud observations throughout the world truly comparable with one another.

Following a 1910 reprint with only slight modifications, the increasing importance of aviation led to the setting up of a new International Commission for the Study of Clouds in London in 1921. This eventually led to a new and expanded Cloud Atlas in 1930, reprinted again with minor modifications in 1939. A completely new edition was agreed in 1947 but was not published until 1956, while minor changes were made in a 1975 edition which, until now, stood as the meteorological community’s definitive cloud classification tool – despite many of the photographs being in black-and-white, mostly 60 or 70 years old, and almost all from temperate latitudes within the northern hemisphere.

This new Atlas has been in preparation for 5 years, and came about partly from pressure from Gavin Pretor-Pinney of the Cloud Appreciation Society to include a ‘new’ type of cloud – originally proposed as asperatus (wave-cloud), now recognised in the new publication as asperitas. Work on asperitas clouds was also undertaken within the Department of Meteorology. The opportunity was also taken to update the photographs used, to expand their coverage from all parts of the globe, and to include much more detail on their synoptic environment (including, in many cases, near-simultaneous satellite imagery). The result is a collection of images which, while meeting is desired training and reference objectives, is also a work of art, and an inspiration to all of us to look up at the sky … the world’s greatest free art gallery!

Weather forecasters face storm of criticism – so is it time for a new look?

By Andrew Charlton-Perez

Former BBC weather forecaster Bill Giles’ criticism of weather forecasts raises questions about how weather is communicated generally.

Mr Giles has hit out at forecasters for regularly warning the public about the potential consequences of imminent severe weather, arguing they are ‘behaving like nannies’ and could cause the public to become ‘immune’ to the advice.

Rain in Reading – watch out for that puddle!

He added the practice of naming storms had become too frequent, and that forecasters should only advise people about potential dangers for ‘exceptionally severe weather’, which occurs once every few years.

But how much weather information is the right amount for the public? How much do they understand? Could an appreciation of the uncertainty of forecasts actually improve our faith in them?

Research at the University of Reading has shown that not only is the average person able to process more complex weather forecast information, they are likely to make better decisions as a result of the additional information.

Scientists at Reading have therefore begun looking at whether the way weather predictions are presented to the general public can be improved.

While the days of people tuning in to the television to learn whether it will rain tomorrow aren’t over yet, smartphone apps have already begun a revolution in the way we obtain forecasts.

Localised forecast

However, these apps often simplify the data to present a black and white picture – for example, rain or no rain – when the reality is, like the Great British skies, somewhat greyer. The original data from agencies like the Met Office or AccuWeather often clearly portrays this uncertainty, yet many apps present only the most likely outcome.

Mobile phone apps also present the user with a highly localised forecast, often with limited information provided about the level of detail the forecast can accurately predict. (We published research into the issues from mobile phone apps in 2015.)

The Met Office responded to Mr Giles’ comments by saying members of the public are more concerned about the impact of weather on their day-to-day lives than the meteorological processes behind it. Making forecasts that allow people to make well informed decisions based on uncertain forecasts  is a really important area of research in which Meteorologists can learn a lot from other fields like psychology and information design, something which our research team at Reading has been exploring.

One of the exciting parts of thinking about how weather forecasts are produced is that technological development has meant that there are an almost limitless number of ways in which forecasts can be produced and tailored to individual end users. The challenge for both the public and private sectors is coming up with innovative ways of displaying weather forecast information that are fun and enjoyable to use, while also being informed by our current understanding of how humans process complex information.

But with this week’s criticism of current forecasts, it seems really important to develop a dialogue between academia, forecast providers and the public about what our weather forecasts will look like in the future.

  • Research on how best to present weather information will be presented by Reading scientists at a Royal Meteorological Society public meeting on 20 September 2017 entitled ‘Message impossible? Conveying weather information in the digital age’.
  • This is a public meeting and we will shortly be launching a way for members of the public to get involved with the meeting and tell us the new ways they would like to see and use weather forecasts.
This blog was originally published on the University’s Connecting Research Forum on 9 March 2017

Winter weather – and cycling in Reading

By Roger Brugge

This tongue-in-cheek look at Reading’s weather in winter and its relationship to cycling safety was prompted by a couple of ice-related accidents experienced by members of staff during the cold and foggy weather of the morning of 24 January 2017 while cycling over the new cycle/pedestrian bridge in the town.

The University’s Atmospheric Observatory, along with several other UK climatological stations, has been recording concrete minimum temperatures since about 1971 (1972 is actually the first year at the university with a complete annual record). Such measurements were begun in the days when road traffic was beginning to increase in volume and the impact of cold weather on road surfaces was identified as being a potential problem. A greater understanding of the climatology of road surface conditions was therefore sought – in addition to the traditional ‘state of ground’ and snow depth reports.

The measurements are made in a similar way to that used in determining the grass minimum temperature – measurements are made using a grey concrete slab about 90 x 60 cm, and about 5 cm thick. If snow falls and covers the concrete slab, then the slab is swept clear of the snow (without disturbing the index of the thermometer) – and the concrete minimum thermometer replaced on the slab.

2017 01 27 Roger Brugge WCD Fig 1

Figure 1. Annual incidence of concrete minimum temperatures below 0 °C (blue) and below -5 °C (red) at the University of Reading during 1972-2016.

As with many winter-time meteorological measurements at Reading there are large inter-annual variations. Figure 1 show that a concrete frost (when the reading drops below 0 °C during a 24-hour period) has varied between about 40 and 100 nights in a calendar year, while a sharp frost (a reading below -5 °C) has occurred on between 2 and 33 days in a year.

Figure 2 shows the distribution of concrete frosts within the year. An average of 75 concrete frosts and 13 sharp concrete frosts can be expected in a 12 month period. Concrete frosts have been recorded as late as the first week of June (1991 and 1994) and as early as 16 September (in 1975).

2017 01 27 Roger Brugge WCD Fig 2

Figure 2. Average monthly incidence of concrete frosts at the University of Reading, averaged during 1972-2016.

On the morning of the accidents in question, the concrete minimum recorded at the university was -4.7 °C – slightly higher than on preceding days. The lowest recorded concrete minimum temperatures at the site are those of -14.9 °C on 14 January 1982, -13.4 °C on 15 January 1982 and -12.5 °C on 10 February 1986. Surface temperatures on a bridge are likely to be lower than those on a road surface in contact with the ground as the latter will be fed by heat from the underlying ground. Of course temperature per se is not a danger to cyclists (unless it is accompanied by a wind that is strong enough to cause significant wind chill to the fingers if the cyclist). This was not the case in the events above, when the presence of (frozen) moisture on the road surface (possibly deposited by freezing fog) was the root cause of the incident. So, thinking of the observations made each morning, which might be used as an indicator of frosty surfaces? The following spring to mind:

  1. Lying snow – we record the state of the ground and the depth of any lying snow, so an indicator of days with lying snow (at 0900 UTC) is easy to determine. In this analysis the presence of any snow cover is included, not just the usual ‘at least 50% cover’ days.
  2. Surface ice – we record this when there is no snow lying on the grass in the observatory. Sometimes lying ice is the result of melting snow that has subsequently frozen, rather than the result of North American-type ice storms.
  3. Frozen ground – this can result (as was the case in January 2017) in frost persisting and building up on the surface throughout the day if the surface remains in shade and the daytime air temperatures do not rise too much.
  4. Freezing fog at 0900 UTC (or in the preceding hour) – if thick enough and prolonged enough this can lead to the deposition of rime and ice. Unfortunately, we only have visibility measurements at 0900 UTC along with indications of fog in the preceding hour if it has cleared by this time.

The incidence of these four conditions were extracted from the daily register of 0900 UTC observations made at the university and the occurrence of these ‘hazardous days’ throughout the year was then examined – see Table 1.

Number of days with a type of weather hazard Total days affected by at least one hazard Likelihood of a hazard day, %
Period Lying snow Surface ice Frozen ground Freezing fog
Jan 1-10 36 0 62 7 100 22
Jan 11-20 48 1 88 20 143 32
Jan 21-31 29 0 83 15 116 23
Feb 1-10 45 0 57 6 106 24
Feb 11-20 50 0 67 6 120 27
Feb 21-28 21 1 36 6 61 16
Mar 1-10 16 0 27 3 44 10
Mar 11-20 8 0 7 2 16 4
Mar 21-31 8 1 2 0 11 2
Apr 1-10 6 0 1 0 7 2
Apr 11-20 0 0 0 0 0 0
Apr 21-30 1 0 0 0 1 0.2
Oct 21-31 2 0 5 0 7 1
Nov 1-10 0 0 7 0 7 2
Nov 11-20 2 0 34 6 39 9
Nov 21-30 3 0 60 9 68 15
Dec 1-10 13 0 73 7 86 19
Dec 11-20 19 0 83 19 109 24
Dec 21-31 39 0 77 15 120 24

Table 1. Occurrence of hazard days at the University of Reading, 1972-2016.

Table 1 suggests that such weather hazards occur on about one day in five to one day in three in the three winter months in Reading, with frozen ground and/or lying snow being the most prevalent type of hazard.

Clearly with these occurrence frequencies, periods of consecutive days with weather hazards are more than likely in most winters. In particular, during 1972-2016 there were 25 instances of spells of at least three consecutive days each of which had greater than 50 % snow cover (an average of more than once every second winter season).

In addition there were 156 of spells of at least three consecutive days each with an instance of hazardous weather in the same period – or 3.4 spells each year on average.

Interestingly, Reading Borough Council in their Winter service plan 2016 – 2017 (see page 10, section 7.5; ) state:

The Council does not promote the use of bicycles during periods of prolonged hazardous conditions. With the exception of shared carriageway routes on a primary or secondary precautionary salting route shared footway/cycleways and remote cycleways are not salted when frost, ice or prolonged hazardous conditions are forecast. Being part of the carriageway, shared carriageway/cycleway routes on the primary and secondary precautionary salting route networks will be salted by default in accordance with the Winter Service Plan.

Cyclists beware!

METEOROLOGY BUILDING GETS A WEATHER VANE AT LAST – BUT CAN YOU UNDERSTAND ITS CODED MESSAGE?

Release Date 16 December 2016

The new weather vane is officially unveiled

A new weather vane with a hidden message has been unveiled on the roof of the University of Reading’s Meteorology building after being chosen as the winning design.

The weather vane was created by Dr Helen Dacre, associate professor in Meteorology, and selected by an expert judging panel. The winning entry was announced by Reading-trained TV weather presenters Holly Green (BBC) and Laura Tobin (ITV).

It was officially revealed to University staff and students on Friday 16 December by Dr Dacre, who was joined on the roof of the Meteorology building by Vice Chancellor Sir David Bell.

The Meteorology building was equipped with a weather vane mast when it was completed in 1996, but has remained without a vane ever since. So, as part of the department’s 50th anniversary celebrations last year, the University turned to its own academics to solve this.

“Since the Meteorology building was opened, we have been quite effectively making the weather – but it remains occasionally useful to know which way the local wind is blowing,” said Professor Giles Harrison, head of the Meteorology department.

“The 50th anniversary provided an ideal opportunity for a weather vane competition, and the mast, forlorn and purposeless for 20 years, has consequently now finally acquired the weather vane it deserves.”

And Dr Dacre’s design, made into stainless steel reality by a specialist company, is complete with a hidden message. But understanding it requires a little meteorology knowledge.

The design is based on the station circle symbol used to plot weather station data on maps – with the accompanying number representing the temperature.

The flag and lines (known as wind barbs) represent the wind speed and direction – a flag represents 50 knots, and the full and half barbs represent 10 and 5 knots respectively. The vane therefore shows 65 knots of wind.

So, eagle eyed students will be able to read 1965 – the year the department was established.

On her design being chosen, Dr Dacre said: “I’m delighted and honoured that my weather vane design has been used to celebrate the 50th anniversary of the Meteorology department.  I hope that it remains on top of the building for the next 50 years.”

Charlie Hooker, from the University of Brighton’s School of Art, who was one of the judges of the competition, said: “What struck me about this design was that it was very elegant. As a sculptor, I could see that it was practical, but the message built into it was very original.”

What is an ORCID?

By Karen Rowlett
Research Publications Adviser,
University of Reading Library

Have you been asked for your ORCID ID yet?

Increasingly, research funders, employers and publishers are asking their researchers to sign up for an ORCID ID.

What is an ORCID ID?

An ORCID® identifier or ORCID iD is a 16-character identifier that can be used to clearly identify you – and not another researcher by a similar name – as the author/owner of an academic output or activity.

Your name is unlikely to be unique and you may find that your research outputs are getting confused with those of another researcher with a similar name.

An ORCID ID can be particularly useful for researchers who have published using several different variants of their name and initials or have published under different names (for example if you’ve changed your name through marriage/civil partnership/divorce or to suit your gender better).

ORCID example 3

 

ORCID IDs can bring together different names that you’ve published under

What is it for?

The idea behind ORCID identifiers is that they should be a stable link between all your research activities – grant applications, manuscript submissions, publications, entries in institutional repositories and your peer review activity.

Your ORCID ID belongs to you and you control what information is added to your ID. You can choose to use your ORCID profile as a mini-CV listing all your publications, work history and funding or you can just use the number to identify you and your research outputs.

Why do I need one?

Many publishers and funding organisations are insisting that researchers supply an ORCID ID when submitting a manuscript or peer review or applying for grants. The list is likely to grow in the future. Here are a few examples:

  • Nature journals
  • PLOS
  • eLife
  • Science journals
  • IEEE publications
  • Hindawi publications
  • Wellcome Trust
  • RCUK

Once you have an ORCID ID, make sure you add it to your registration details on manuscript submission sites and other sites such as ResearchFish.

Who is behind ORCIDs?

ORCID is a non-profit organisation that is governed by a board of directors with wide stakeholder representation. Member organisations such as funders, publishers and institutions pay a membership fee but signing up for an ORCID is free.

How much will it cost?

Registration for an ORCID ID is free and maintaining this free status is one of the core principles of the ORCID organisation. To sign up, you will need to agree to ORCID’s Privacy Policy and Terms of Use. You need not have an official affiliation and there is no set of requirements to qualify as a researcher. Adding data to your record, changing your record, sharing your data, and searching the registry are also free.

What does an ORCID ID look like?

Your ORCID ID is a 16 character number that identifies you and not someone else with the same name.

ORCID example 2

 

An ORCID ID is a 16-character identifier that is associated with your name and scholarly outputs

 

You can see a (fictitious) example of an ORCID record for Josiah Carberry, an expert on Cracked Pots, here: http://orcid.org/0000-0002-1825-0097

ORCID example

 

How do I register for an ORCID?

It is very easy to sign up for an ORCID ID – registering for your ORCID Identifier takes about 30 seconds.

You can then add as much personal information as you want to your record. The minimum recommendation is that you add the country that you are working in, some keywords about your research area and possibly a link to your university webpage. It is always a good idea to add an alternative email address just in case you ever have difficulty accessing your account.

You can add much more information about your research outputs and use your ORCID like a mini-CV.

Help and support

Take a look at our ORCID library guide for more help on how to sign up and populate an ORCID ID or contact the University’s Research Publications Adviser. The ORCID support centre is also full of useful information.

More information from ORCID

A short vimeo video shows how ORCID IDs can help researchers gain credit for all their scholarly activities.

Open Access week – and atmospheric effects of solar eclipses

2016 08 30 - Phil Trans TA2077 banner

Next week is ‘Open Access Week’ , and to celebrate this, all Royal Society journal content will be completely free to access from Friday 21 October until 6 November.

Solar eclipses rarely cross populated regions, but provide great opportunities both for science and science outreach when they do. The recent 20 March 2015 solar eclipse tracked across the Atlantic, giving substantial solar radiation changes in the UK and Iceland, and totality in the Faeroes. This Theme Issue of the Philosophical Transactions of the Royal Society brings together a unique series of studies on effects of eclipses on the weather, placed in the context of societal responses to eclipses. Professor Giles Harrison from this department was joint lead editor on the issue, and the journal includes contributions from many members and ex-members of the Department of Meteorology at the University of Reading on a very wide variety of topics.

Investigating effects of eclipse-induced weather changes (e.g. in surface air temperatures, wind and cloud amount) has a long history, usually exploiting observations made during the eclipse for comparison with comparable non-eclipse conditions the day before or after. New approaches to study the weather-related changes are now possible, employing high resolution numerical models of the atmosphere in which an eclipse can be turned on or off at will, combined with the extensive coverage of good quality amateur and professional weather data available. This issue includes work analysing surface, balloon and satellite observations, alongside high resolution numerical modelling studies. In doing so it defines a new interdisciplinary research area in eclipse weather, closely focussed in scope, but diverse in the work it contains.

The contents of this special issue, available online (FREE Open Access 21 October to 6 November) and in print, is given below:

Introduction: The solar eclipse: a natural meteorological experiment: RG Harrison, E Hanna
Symbolism and discovery: eclipses in art: I Blatchford
Atmospheric changes from solar eclipses: KL Aplin, CJ Scott, SL Gray
Meteorological effects of the solar eclipse of 20 March 2015: E Hanna, J Penman, T Jónsson, GR Bigg, H Björnsson, S Sjúrðarson, MA Hansen, J Cappelen, RG Bryant
On the variability of near-surface screen temperature anomalies in the 20 March 2015 solar eclipse: MR Clark
Satellite observations of surface temperature during the March 2015 total solar eclipse:
E Good
Meteorological responses in the atmospheric boundary layer over southern England to the deep partial eclipse of 20 March 2015: S Burt
Effects of the March 2015 solar eclipse on near-surface atmospheric electricity: AJ Bennett
Terrestrial atmospheric responses on Svalbard to the 20 March 2015 Arctic total solar eclipse under extreme conditions: JM Pasachoff, MA Peñaloza-Murillo, AL Carter, MT Roman
Coordinated weather balloon solar radiation measurements during a solar eclipse: RG Harrison, GJ Marlton, PD Williams, KA Nicoll
On the detection and attribution of gravity waves generated by the 20 March 2015 solar eclipse: GJ Marlton, PD Williams, KA Nicoll
Using the ionospheric response to the solar eclipse on 20 March 2015 to detect spatial structure in the solar corona: CJ Scott, J Bradford, SA Bell, J Wilkinson, L Barnard, D Smith, S Tudor
Eclipse-induced wind changes over the British Isles on 20 March 2015: SL Gray, RG Harrison
Numerical simulations of the impact of the 20 March 2015 eclipse on UK weather: PA Clark
The National Eclipse Weather Experiment: use and evaluation of a citizen science tool for schools outreach: AM Portas, L Barnard, C Scott, RG Harrison
The National Eclipse Weather Experiment: an assessment of citizen scientist weather observations: L Barnard, AM Portas, SL Gray, RG Harrison

Phil. Trans. R. Soc. A 2016 374: access content online

Launching a weather balloon at the University of Reading

Weather forecasts these days are hi-tech: satellites orbiting the Earth continually watch the current weather and feed this information into some of the largest supercomputers in the world. But satellites can’t give us a complete picture of the current weather and, to fill in the gaps, we use a seemingly low-tech solution: helium balloons. Thousands of them are launched from weather stations around the world every day.

Except that these balloons are anything but low-tech because dangling beneath each is a box crammed with miniaturised electronics that measures the atmosphere from the ground to 20 km or more above.

Earlier this summer the YouTuber and atmospheric scientist Simon Clark visited the atmospheric observatory here at the University of Reading to film Dr Graeme Marlton launch a weather balloon and follow its journey up through the atmosphere. Simon has since uploaded the first of three videos that he filmed at the department.

More of his videos on Simon Clark’s YouTube channel.

Early thoughts on winter 2016-17 …

By Chimene Daleu

In the UK, colder winter weather is usually caused by high pressure developing to the north, which allows cold arctic or polar continental air masses to push towards the UK. Last year, winter was much milder than average with a mean temperature of 5.5°C, 1.8 degC above the average. This was the result of the influences of El Nino and the westerly phase of the Quasi-biennial Oscillation (QBO).

Since January 2016, there was evidence of ENSO-neutral conditions and a slight trend towards La Nina during the rest of the northern hemisphere summer.  However, there is a higher chance that La Nina will be maintained through the autumn and winter. When coupled with an easterly phase of the QBO the coming winter may turn out significantly different to the last one.

2016 10 06 Chimene Daleu WCD Fig 1

Figure 1. Source: http://www.theweatheroutlook.com/twoother/twocontent.aspx?type=hpnews&id=3300&title=Winter+2016%2F17

Discussion
The winter 2015-16 produced one of the most powerful polar vortex systems in many years, giving a relentless spell of very wet, very mild and very windy conditions across the UK and a distinctly positive North Atlantic Oscillation (NAO). In addition, during last winter we were entering into one of the strongest El Nino events in many years and this, without doubt, had some influence on the northern hemisphere’s weather patterns. Equally important was the westerly phase of the QBO. This combined with solar activity and El Nino helped produce a distinctly cyclonic and unsettled winter period with little cold weather.

In contrast to winter 2015-16, this coming winter period we are moving towards near neutral El Nino conditions and with an ongoing trend towards La Nina in the coming months. At the moment some of the main forecast models (see Figure 2) highlight that through this coming winter period a weak La Nina is expected to be in evidence. Clearly this will be in complete contrast to the ‘strong’ El Nino of last winter.

Whilst there is always an uncertain connection between ENSO and the weather across the UK, it is expected that a weak La Nina event wouldn’t aid in strengthening the northern hemisphere’s polar vortex like the El Nino event of last year did. A weak La Nina can promote more in the way of northern blocking through the winter period, but this is certainly an uncertain prediction at any time due to other factors.

2016 10 06 Chimene Daleu WCD Fig 2

Figure 2: Source: http://www.theweatheroutlook.com/twoother/twocontent.aspx?type=hpnews&id=3300&title=Winter+2016%2F17

The QBO phase this winter is expected to be the opposite of last year, with an easterly phase expected. While a westerly phase QBO essentially adds more ‘fuel’ to the overall winter-setup, an easterly phase of the QBO promotes a more disorganized polar vortex. The more disorganized the polar vortex is through the winter period, the greater the likelihood of colder outbreaks and less in the way of stormy conditions.

Sunspot activity has been declining since a peak around the winter of 2014-15. However, the severe winters around 2009 and 2010 did coincide with a particularly noteworthy solar minimum, as can be seen on Figure 3. Whilst the connection between solar activity and winter weather is a vague one, the general decline in solar activity is set to continue through this coming winter period.

2016 10 06 Chimene Daleu WCD Fig 3

Figure 3: Source: http://www.theweatheroutlook.com/twoother/twocontent.aspx?type=hpnews&id=3300&title=Winter+2016%2F17

Summary
Early indications suggest the coming winter may be significantly different to the last one. The combination of lower solar activity, a weak La Nina and an easterly QBO phase may favour a less cyclonic pattern and perhaps increase the risk of colder outbreaks.

 

 

 

No heatwave in Reading in July 2016 – but two in December 2015!

By Roger Brugge

Maybe the title of this piece may seem rather odd – but then ‘what is a heatwave?’

Perhaps surprisingly, in the UK there is no accepted definition for a heatwave. The Met Office tend to use the World Meteorological Organization definition of a heatwave which is “when the daily maximum temperature of more than five consecutive days exceeds the average maximum temperature by 5 degC, the normal period being 1961-1990” [Link 1].  In the popular press the impression is gained that a heatwave is a hot spell lasting at least two days.

In practice, the definition of a heatwave varies from country to country and, rather like a drought, it can depend upon the use to which the definition is being put. Thus humidity, minimum temperature and other meteorological factors relating to human physiology can also be included in a definition. The WMO definition presumably refers to the 1961-1960 period as this is the current standard 30 year averaging period used in many areas of meteorology. Arguably, the actual temperature itself should figure in the definition – the public might take some convincing that the South Pole might experience a heatwave!

Here in Reading we have a weather station that has been operational on the Whiteknights campus since 1968 – prior to that records have been kept closer to the centre of the town along the London Road since 1901. The relative urban (London Road) – rural (Whiteknights) differences of the two sites make it difficult to directly compare day-to-day temperature measurements between the sites.

So, I thought I would examine daily maximum temperatures as observed at Whiteknights and employ this definition of a heatwave:

A period of five or more consecutive days on each of which the daily maximum temperature is more than 5 degC higher than average for the period 1981-2010. The long-term average is calculated here on a day-to-day basis.

Results at Reading

This definition produced 35 heatwaves in the 48.5 years since 1 January 1968, with some interesting results:

  • There were just 3 heatwaves during 1968-1980 – of which the longest (and also that for the entire 48.5 years) was that lasting for 17 days from 22 June 1976.
  • The second-longest heatwave lasted for just 11 days from 3 August 2003.
  • During 1981-1990 there were 7 heatwaves, with 6 in the period 1991-2000. During 2001-2010 we had 10 heatwaves, with 9 since the beginning of January 2011.
  • 16 heatwaves have begun during one of the summer months (June-August), while 14 have started at some time during March-May (i.e. in spring).
  • The only autumn heatwave was the six-day long one starting on 28 September 2011, while there have been four that started during winter months – namely those starting on 11 February 1998, 11 December 1998, 15 December 2015 and 25 December 2015.

So, we had a heatwave starting on Christmas Day last year. In fact had the temperature not dropped slightly on 23-24 December (the maximum temperatures were just 4.5 degC and 4.3 degC above normal on these days, respectively), December would have had a 16 day heatwave!

The bullet points above indicate a tendency towards an increasing number of heatwaves – as might be expected in a warming climate. This is confirmed by Figure 1.

2016 07 27 Brugge_heatwave_fig1

Figure 1. The number of heatwave days during 1968-1991 (blue), 1992-2015 (red) and 1968-2015 (black). Notes that monthly totals of less than 5 days are an indication of a heatwave spread over two months.

Figure 1 shows that the second half of the period produced more heatwave days than the first half, the exception being in June due to the remarkable events of the summer of 1976 [Link 2] – which are still talked about to this day! Moreover, the warmth of December 2015 also stands out –see also [Link 3], while both April and May seem to fare better than August.

2016 07 27 Brugge_heatwave_fig2

Figure 2. The number of heatwave days each year during 1968-2015, along with the ten-year running mean plotted on the final year of the ten-year period.

Looking at the annual heatwave day totals (Figure 2) suggests less of a warming trend in recent years than does Figure 1. With the exception of 1976, there were less than 10 heatwave days each year until 1989; since then it is difficult to see much of a trend in the 10 year running mean count – 1989 and 1995 led to a peak in the running mean by 1996 but since then the running-mean has declined (slightly).

‘Proper heatwaves’

Of course, in the public’s mind a UK heatwave is one with high temperatures, and not just large temperature anomalies – i.e. the South Pole argument mentioned earlier.

If we examine the 35 heatwaves and rank them according to the average maximum temperature or the highest temperature achieved during the heatwave, then the results are those shown in Table 1.

Table 1. Top nine of the 35 heatwaves, ranked by average of highest maximum temperature.

Heatwave start date  (ymd) Heatwave duration, days Highest temperature, °C Heatwave start date (ymd) Heatwave duration, days Mean maximum temperature, °C
2003 Aug 3 11 36.4 1995 Jul 29 6 31.6
2006 Jul 16 7 35.3 1976 Jun 22 17 31.4
1976 Jun 22 17 34.0 2003 Aug 3 11 31.2
1995 Jul 29 6 33.6 2006 Jul 16 7 31.2
1989 Jul 20 6 33.2 1989 Jul 20 6 30.6
1983 Jul 11 7 31.6 1983 Jul 11 7 30.5
2006 Jun 30 5 31.4 2009 Jun 28 5 29.7
2009 Jun 28 5 30.4 2006 Jun 30 5 29.6
2013 Jul 13 7 30.2 2013 Jul 13 7 29.4

 

This table highlights the appearance of the same nine heatwaves in both sets of rankings. Omitting the entry of 1976, then the other years that appear are those of 1983, 1989, 1995, 2003, 2006 (twice), 2009 and 2013.

With only one year from the period 2010-2016 in the list, maybe this has fuelled the idea that we are having a run of poor summers without any heatwaves?

Further reading

[Link 1] http://www.metoffice.gov.uk/learning/learn-about-the-weather/weather-phenomena/heatwave

[Link 2] http://www.metoffice.gov.uk/news/releases/2016/heat-wave

[Link 3] http://blogs.reading.ac.uk/wcd/2015/12/18/not-yet-christmas-but-has-spring-sprung/