Synapse Science Magazine #11 Special Issue

FR

EE

SYNAPSE ISSUE 11 - September 2015

University of Bristol

THE

ENVIRONMENTAL

ISSUE

Where are the bees?

The

Rising Tides of Disease Climate Chaos ws ! e i v r e I nt lusive exc

EDITORIAL

The Team Rosie Hayward Editor in Chief

Thien Ho

Vice President

Amy Newman

Secretary & Senior Editor

Louisa Cockbill

Treasurer & Senior Editor

Nick Henden

Chief Graphic Designer

Melissa Levy

Managing Editor

Toby Benham

Managing Editor

Welcome to

SYNA PSE Science Magazine

T

he 11th issue of Synapse Science Magazine is here and to celebrate Bristol being named the European Green Capital of 2015 we’re bringing you an environmental special. Articles range from opinions on climate change denial to ecotourism, all with a focus on the environment, what it does for us, and how we can preserve it. This issue also includes exclusive interviews with Professor Tim Palmer from Oxford University on climate computing, and with Professor Stephen Lewandowsky on the Anthropocene and Professor David Fermin on solar energy, both from the University of Bristol. Studies of how we impact the natural world encompass all walks of science, and so for all scientists and science enthusiasts, we give you Synapse: The Environmental Issue.

E: synapsebristol@gmail.com

Mutanu Malinda Tom Stubbs

Media Co-Director

Felicity Ellen Stubbs Senior Editor

Daisy Dunne Senior Editor

Cover Photograph

Editors

Media Co-Director

Sophie Groenhof Katie Porter Stephanie Bates Marta Plaszczyk Hayley McLennan Rachel Greenwood Jessica Towne George Thomas

Hayley Muir

Synapse wishes to acknowledge the support of the 2 | SYNAPSE

Guarantors of Brain.

CONTENTS

What Urban Trees do for us Using Roads to Overcome Global Warming Black and White: The Science behind the Badger Cull

Stepping into the Age of Man Rising Tides of Disease Wind Energy: The Future of Power Generation?

The Case for Solar Energy Climate Change, Chaos & Inexact Computing Atmospheric Aerosols:

Why do we need to understand their properties?

The Environment and Radiation Climate Change Denial: Why do people continue to Deny Climate Change?

Ecotourism: A different shade of green

Where are the Bees?

Synapse Strips

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WHAT URBAN TREES DO FOR US Amy Newman

Carbon capture

The trees lining your average suburban street may seem unassuming but there’s more to them than meets the eye. With pressure to develop on high-value city land, it can be easy for us to forget that trees in built-up areas provide services for us simply by being there. Here are the five main benefits campaigners and scientists say urban trees bring to city-dwellers.

Human health The most obvious advantages of trees in urban areas are the wellbeing benefits of green community spaces for recreation and relaxation. Trees also help prevent of asthma and skin cancer by filtering air, reducing smog formation and providing shade from solar radiation. It has even been shown that hospital patients in rooms with views of greenery made a quicker recovery after surgery than those looking out at buildings.

Boosting biodiversity Trees provide a welcome refuge and habitat for many species, most obviously garden birds. In otherwise harsh urban locations, trees may be used for food, nesting or sheltering from the elements. As well as this, trees provide indirect benefits to wildlife by hosting insect species. This provides a food source for larger animalseven bats. Willow trees alone may support up to 450 individual species!

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A major role of urban trees, particularly in our busiest cities, is helping to control pollution. It’s common knowledge that burning fossil fuels causes the greenhouse gas carbon dioxide to build up in our air and atmosphere. However trees act as ‘carbon sinks’, absorbing and storing CO2 as part of their everyday photosynthetic activities. This removal of carbon helps keep our urban air clean and reduce temperatures.

Energy efficiency Trees near houses help us use less energy at home and save on bills all year.

By acting as windbreaks in the winter, they increase the efficiency of houses’ insulation by helping stop heat being swept away from the building. In the summer months, trees provide shade and cool the air.

Evapotranspiration carried out by the leaves cools the surrounding space by releasing evaporating moisture. In the autumn, more light is let into homes when deciduous trees lose their leaves.

Crime prevention Perhaps most surprisingly, urban trees even reduce crime risks in towns and cities, and have been found to lead to lower incidences of graffiti in particular. One study found that urban spaces planted with trees had a 90% chance of remaining free of graffiti, compared to a 10% chance in areas without them. It’s thought that by making areas look pleasant and less threatening, trees enforce a greater sense of ownership and community. With people using streets more, any criminal activity becomes conspicuous and more likely to be discovered.

Lily Clayton

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he UK government is encouraging people to invest in electric cars by giving rewards to those who decide to ‘go green’. Perhaps the greatest environmental benefit of an electric car is that it doesn’t burn fossil fuels and so doesn’t release carbon dioxide into the atmosphere and contribute to global warming. But the price and size of electric car batteries, along with the time taken to fully charge, seems to be putting people off.

Now the Highways Agency is testing out a new idea to make electric cars more appealing: using ‘electrified roads’ that generate electricity to charge cars as they drive over them. Electric cables in the road, supplied by a high-voltage cable running alongside the road, can generate an electromagnetic field when a coil attached to an electric car passes over them. This can then be converted into electricity to charge the car.

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Using Roads to Overcome Global Warming

This method is already being used to charge stationary buses in Milton Keynes at charging points and has been inserted into some roads in South Korea to charge moving buses. Although the ability to charge cars on the go would allow battery sizes to be reduced and also shorten charging times, the Highways Agency estimates that this idea would only be beneficial for public transport, rather than private cars, due to the costs involved.

Roads are also the focus of generating electricity in other ways. Road surfaces can be plated in specialised solar panels, becoming sources of renewable energy whilst still remaining fully-functional as highways. It has been estimated that a 1-mile stretch of motorway covered in solar panels could provide 500 homes with electricity, so covering all UK motorways could generate enough electricity for half of the UK’s homes. The idea has been trialled in the USA and the Netherlands, and researchers are currently developing panels that are strong enough to withstand the pressures of vehicles driving over them and which could be inserted into existing roads.

There are many potential benefits of solar-panelled roads other than generating renewable energy. They can be fitted with LED lights to display road markings and deliver warnings to drivers, and also with heaters to melt away snow and ice, making driving during the night and in winter safer.

It seems that in the future, the very things thought to be major causes of global warming could be generating the renewable energy we need to fight it.

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BLACK & WHITE The Science Behind the Badger Cull Rachel Baxter

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he controversial method of badger culling has triggered waves of criticism throughout the UK, citing the authorities’ apparent disregard of scientific evidence. Its aim is to reduce bovine tuberculosis (bTB) in cattle, a lethal disease caused by the bacterium Mycobacterium bovis, which can be spread by roaming badgers. However, despite their role in transmission of the disease, research suggests that culling badgers may not be the best option.

Although it is true that badgers carry bTB, recent data suggests that only around 15% are infected in the UK. Moreover, research has found that it is not only badgers that harbour the disease; it can also be carried by moles, rats, deer, sheep and even cats. Therefore, badgers are not solely responsible for bTB distribution and if the cull is justified, should we not be culling a range of other species too?

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In fact, the majority of research shows that culling badgers has little impact on the number of cattle infected with bTB and that it can even exacerbate the situation.

The most in depth study regarding culling to date is the Randomised Badger Culling Trial, which took place between 1998 and 2006 and cost over 50 million pounds.

This trial involved trapping badgers in cages and shooting them. Although it did reduce bTB incidence by 19%, it caused a significant bTB increase in regions surrounding the culling zone, with bTB cases in cattle increasing by 29% in areas 2 kilometres away. This phenomenon is known as the perturbation effect. It occurs because reduction in badger numbers allows surviving badgers to move around more freely, expanding their territories and interacting with new populations.

This leads to the spread of bTB between badgers that would not have previously

come into contact with one another, resulting in a higher proportion of badgers carrying the disease. The impacts of the perturbation effect on cattle were found to be so substantial that they cancelled out any positive effects of culling. The Randomised Badger Culling Trial is the most peerreviewed and well-regarded piece of badger cull research to date and it clearly shows that badger culling is not successful in reducing bTB in cattle.

the majority of research “shows that culling badgers has little impact on [bTB infection rates]

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Then why, you might ask, is culling still occurring in parts of the UK? In fact, more recent culls have simply provided further evidence against the method. Culling trials were reinitiated in October of 2013 in Gloucestershire and West Somerset but were cut short due to failure to meet targets.

These culls were also heavily criticised by the public and animal welfare organisations due to their apparently inhumane nature.

The badgers were killed by free shooting with up to 18% of the animals taking longer than 5 minutes to die. However, culling trials began again in September 2014 to analyse the humaneness of trapping the badgers and shooting them as opposed to free shooting. This culling trial was originally intended to be nationwide but due to lack of success in previous trials it was restricted only to Gloucestershire and West Somerset. The outcomes are yet to be revealed but it is likely that they will follow the trends of previous, ineffective trials.

Due to the severe present lack of evidence in favour of the cull, other modes of bTB reduction have been suggested.

For example, badger vaccination trials have proved very successful, reducing the number of infected badgers by 74%.

The vaccine used is Bacille CalmetteGuérin (BCG), which is exactly the same as the vaccine used in humans, although badgers receive a higher dose. Although the vaccine is costly, in order to reduce bTB instances only some individuals from a population need to be vaccinated as simply having some resistant animals leads to ‘herd immunity’ which significantly reduces the chance of disease transmission between individuals. Consequently, badger vaccination is more efficient than culling, as well as being more humane.

Perhaps the findings will lead to termination of the badger cull, although this seems unlikely, as so far, the government appears to have ignored the science. This could be due to attempts to win the votes of farmers who desperately want action to prevent bTB, or perhaps there is hope that future trials will prove the cull to be a success. Regardless, it is clear that culling is not constructive and that other practices, such as vaccination, will likely provide a far more logical solution.

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INTERVIEW

Stepping into the Age of Man

Welcome to the Anthropocene

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ext year a group of scientists will meet to discuss whether or not we are now entering a new epoch in Earth’s history. The International Anthropocene Working Group represent a scientific movement bringing all manner of environmental matters together. They

aim to find out if we have affected our planet so much that we have initiated a new geological epoch characterised by our influence.The name Anthropocene comes from the Greek words for “human” (“Anthropo-”) and “new” (“-cene”). The origin of this term has its deepest roots

Being a relatively newly coined term, is the concept of the Anthropocene widely accepted by scientists?

Millions of years from now, might our influence on the planet be easily seen in the fossil record?

Within the geological and climate community it appears to be fairly widely accepted. What is more notable is that scholars in the humanities and social sciences seem to have embraced the term with considerable verve. That’s not entirely surprising given that the implications of the Anthropocene are primarily social rather than geological. This has been recognized by some physical scientists: For example, Prof Hans Joachim Schellnhuber (Chief Government Advisor on Climate for the German G8-EU twin presidency in 2007), is on record as stating that: “Speaking as a natural scientist, I think 90% of research [on global change] will have to be done by the social scientists.”

I would expect there to be distinct traces in the biosphere (or whatever proxy indicators of our present biosphere will be around 1 million years from now). We are presently losing species at a rapid clip, and like previous mass extinctions, I would expect the current one to be detectable in fossil records years from now. How could it not be if all the others are?

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in Russian biological studies from the 1960s, but it was not until the 1980s that the term was popularised by the atmospheric scientist Paul Crutzen and the ecologist Eugene Stroemer. Previous studies had simply used it as another name for the Quaternary period (the period of geological time we are currently in, representing the last 2.6 million years).

However, Stroemer and Crutzen used it to suggest that factors such as species loss, climate change and other man made environmental issues have caused so much change that the Earth’s rocks may record our own actions alongside other great catastrophes of prehistory. There is debate

as to when this epoch started; it could have been as early as when humans started farming or as recent as the first nuclear tests, but the concept itself is gaining significant traction.

Are we “past the point of no return”?

Are we capable of the social/economic changes needed to reverse the damage we’ve done to the Earth so far?

Will this newly categorised time period be more likely to grab the attention of policy makers to address such issues?

I don’t think we can “undo” the Anthropocene and return to a preAnthropocene epoch, no. That would require reducing atmospheric CO2 to pre-industrial levels which is simply not possible under any scenario known to me and there isn’t a single voice out there that I can think of that would actually believe that. However, that doesn’t mean that we cannot limit the damage we are doing to the Earth. There are some workable social and economic scenarios out there that tell us how to achieve that and how to decarbonize our economy fairly rapidly. Are we, as a species, capable of that? Sure; but we are also capable of stuffing up big time.

Professor Stephan Lewandowsky is a cognitive scientist at Bristol’s School of Experimental Psychology and Cabot Institute with a research interest in how science (including climate science) is presented to and perceived by the public. I approached him with a few questions about the Anthropocene and its implications:

That’s an open question. Ultimately, it’s all about politics and policy (in that order).

I think people are capable of a myriad of different things, and sometimes we solve even wicked problems. Tobacco control and the ozone hole come to mind. So in principle there is no reason that we cannot also shape the Anthropocene in a more constructive manner. Whether that will happen is an open question.

James Ormiston synapsebristol.blogspot.co.uk

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he devastating effects of global warming have, so far, been largely presented in violent meteorological conditions. Mostafa Rokonuzzaman, a village farmer of south-western Bangladesh, was suffering a limp crop yield due to extreme weather fluctuations in April of 2009. His impassioned speech to his fellow villagers – that prevention of these conditions was urgently required - was one of despair.

Sadly, this was only the beginning.

A month later, Cyclone Aila (May 2009) tore through his village and wrecked the homes of many of its inhabitants – 190 people died from the impact alone. In earlier years, Hurricane Gilbert (1988) raged for nine days and left a death toll of 433 on the Gulf of Mexico and Jamaica.

These disasters, and others like it, are attributed to the atmospheric changes associated with global warming. An average increase from 9 to 16 storms per year was seen from 1925 to 2005.

But there is a less visible threat; an ever growing threat which thrives in a heated climate, a threat with the potential to forge more widespread death than any tropical cyclone. This threat is the frightening spread of infectious disease.

To illustrate, the WHO (World Health Organisation) states that up to three million deaths per year are caused by the mosquitoborne Malaria, a disease of single-celled parasitic protozoans which multiply in the liver and cause rupturing of red blood cells. Mosquitoes are also culprits in the spread of Sylvatic Yellow Fever, where 90% of the 20,000 annual deaths occur in Africa alone. Cholera, propagated by the waterborne bacterium Vibrio cholerae, causes a yearly mortality of up to 120,000 individuals. While these illnesses are, of course, perpetuated by poor sanitation in developing countries in particular

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Rising tide

The lethal threat

(instances of Cholera are high in Kinshasa, Africa, where 38% of the population have no piped water access), global warming plays an increasingly large part. But how?

Vibrio cholerae thrives in warm, damp environments. An increase of rainwater by 200 ml causes a doubling of this bacterium (states Mohammed Ali, International Vaccine institute), while a rise of 1 degree Celsius causes a surge of reproduction, by a factor of 1.6. Indeed, this very correlation was found in Zanzibar; between 1999 and 2008, the rising levels and temperature of rainfall were closely followed by increasing outbreaks of Cholera. If sea levels do rise a further 7- 13 inches by the end of the century, as predicted by researchers at The National Geographic, the resultant breeding ground for Vibrio cholerae could prove devastating in countries of low sanitation.

These sea level rises, cause by glacial ice melting, are also subject to warming; an increase of 0.6 degrees Celsius has been found in oceans globally.

es of disease

ts of global warming

With insect-borne diseases such as malaria, global warming favours not only the bacterium at hand, but also the host.

Malaria has historically affected African countries where conditions are hot and damp; it’s responsible for 38% of child deaths in Sierra Leone, and the leading cause of death in Burkina Faso, both countries in the west of the continent. This is somewhat anticipated, as Africa provides perfect conditions for the insect at hand.

However, could rising temperatures worldwide lead to the migration of mosquitoes to other areas?

Yes, says the London School of Hygiene and Medicine. Rising temperatures in the mountainous high-altitude tropics has shown a steady and determined rise in the rate of malaria, which retreats only in the cooler months. These regions, previously a place of privilege to inhabit due to lower malaria rates, have paradoxically become the most dangerous areas. Indeed, warns Menno Bouma, co-conductor of the research, 43% of Ethiopia’s population live in the Debre Zeit; at 1200 – 2410 metres above sea level, almost half of the country’s population are now at risk.

Thus, while dramatic tropical cyclones and rising sea levels are testament to the presence of global warming, the hospitality it offers to bacterial disease is truly ominous; illness is on the rise. It’s a cruel paradox that colder climates such as the UK who are financially more equipped to tackle the epidemic, are the least affected.

Campaigns such as NetForLife Africa aim to provide prevention of Malaria, while nurses volunteer tirelessly off-duty. But as Mostafa Rokonuzzaman pleaded in 2009, global warming is the underlying issue. Tackling this climatic change is urgently required.

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Wind Energy The Future of Power Generation?

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rom ancient times, historical records contain evidence of people harnessing wind energy to generate mechanical power. Wind energy is a free, renewable resource that does not contribute to air contamination during electricity generation. Yet despite these compelling advantages, it was not until the 1970s that most governments, motivated by oil shortages, became seriously interested in expanding the usage of commercial wind turbines. It was realized that the availability and low cost of fossil fuels is restricted by political interference and eventually reserves will become exhausted.

Meanwhile, nuclear power generation was causing safety concerns. Since then, windpowered electricity generators have grown in popularity, today operating in various settings and being the fastest growing energy source in the world.

Since the power developed by wind energy conversion systems is mostly influenced by wind velocity, it is necessary to identify a site where the wind is strong. It is also important that the behaviour of the wind in that location is analysed over time as wind patterns are often subject to change.

Hence, an optimal wind turbine design can be selected for the specific wind farm.

Horizontal Axis Turbines

Horizontal Axis Turbine

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The most common type of wind turbine is the horizontal-axis design with its rotational axis almost parallel to wind direction. It consists of a rotating blade converting kinetic energy from the wind into mechanical energy rotating a shaft. The shaft is connected to a drive train with a gearbox and a generator. The most effective power output can be achieved by controlling the generator speed and blade pitch. This type of wind turbine can often be seen throughout the UK, with the individual turbines being grouped together into a power plant, also known as a wind farm. The key advantages of horizontal axis turbines are low cut-in wind speed, ease of furling when the wind is too strong and relatively high power efficiency.

However, they require the gearbox and generator to be placed on top of the tower and so there is a need for an additional drive to orient the turbine towards the wind, hence making the design more complicated and expensive.

Vertical Axis Turbines Another type of wind turbine is the vertical-axis turbine; mainly designed for domestic use, it is lightweight and more compact than the horizontal-axis variety.

The key difference in verticalaxis turbines is the fact that the main rotor shaft rotates in a direction almost perpendicular to the wind and the remaining components are located at the base of the plant. Additionally, vertical axis turbines can receive wind from any direction so complicated yaw devices can be eliminated. However, they also have some major disadvantages. The key problem is that the turbines are not self-starting, requiring additional mechanisms to start from rest. The system also has lowered efficiency as blades have to pass through aerodynamically dead zones. Lastly, the possibility of the blades running at very high speeds increases the probability of system failure.

Vertical Axis Turbine

Future of Wind Energy Recent advances in wind energy generation include plans to launch high-altitude airborne turbines on a wide scale, such as the Buoyant Airborne Turbine (BAT) manufactured

by Altaeros Energies. The design integrates aerospace and wind turbine technologies to give a product aimed at customers requiring high capacity power at low cost. The BATs will consist of four main components: a heliumfilled shell; a conventional, light-weight three-blade turbine; a portable ground station and tethers holding the turbine in place thereby allowing power to be transmitted to the ground.

Despite all of their advantages over conventional fossil fuels, systems exploiting wind energy are often disliked by the public. While some consider them to be a noisy eyesore, others worry about the threat to wildlife habitats that wind turbines may cause. For example, birds of prey are likely to come into contact with turbines located at high altitudes, often resulting in their death or injury. However, research shows no significant correlation between reduction in bird populations and wind turbine use. Nevertheless, it is important that potential sites for wind farms are carefully selected as well as ensuring that technologies to tackle problems caused by current wind turbine designs continue to develop.

The Buoyant Airborne Turbine

Marta Plaszczyk

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INTERVIEW

How does a solar cell work?

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he main advantage associated with solar energy is the ability to generate electricity via manipulation of a free and globally available commodity: sunlight. Sounds good, but how does it happen? Solar cells are generally made from a semiconducting material, defined electronically as being between a metal and an insulator. Let’s take silicon solar cells – the predominant model that we see on rooftops - as an example. Silicon is able to absorb visible light, in the form of photons, to generate electron and

hole pairs. The sustained separation of electrons and holes is key and explains why metals and insulators fail to convert solar energy successfully. However, the generation of free electrons by photons (the photovoltaic effect) is only part of the process.

These electrons must also be guided in the right direction to generate an electric current. This is achieved by doping silicon with foreign materials to create a ‘p-n junction’. Positive-type

The Case for Solar Energy In a one off interview for Synapse Magazine, Professor David Fermín explains why solar energy is the most promising energy solution we currently possess.

Can you explain your background and how you ended up working at Bristol University?

I am originally from Venezuela where I did my degree in chemistry. For my final year project, I decided to work in the area of electrochemistry – a subject that I found confusing and wanted to understand. This involved work on conducting polymers, which were very in fashion at the time.

Subsequently, I completed a PhD on semiconductors at the University of Bath, followed by a postdoc position at Lausanne in Switzerland working with molecular systems. However, I wanted

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to come back to solar energy conversion – a topic I had always been interested in.

Bristol University provided me with an opportunity to research this and I have been here ever since.

How does solar energy compare to other renewables?

Solar energy is several orders of magnitude of power higher than anything else available to the planet. Every day, 120,000 terawatts of power reach the Earth from the sun and what we need from that is just a fraction, about 50 terawatts or so. By the numbers it’s the best. Nuclear energy can’t

current (i.e. electricity). Overall, energy from the sun is converted to electrical energy. However, there are multiple aspects that limit efficiency such as photon absorption and quantum efficiency.

Therefore, improving the effectiveness of the operation is key to developing future solar devices.

Toby Benham Ph ot on

(p-type) silicon may be doped with boron for example. Boron has fewer electrons (3) in its outer shell, compared to silicon (4), thus creating an excess of holes. On the other hand, negative-type (n-type) silicon involves an excess of electrons.

This can be achieved by introducing an element such as phosphorus, which has more electrons than silicon in its outer shell (5). Bringing these two types together creates something called a ‘depletion layer’ at the p-n junction (where p-type meets n-type). Consequently, a weak electric field is generated. It is this field that guides photo-generated electrons into a direct

Electron

n-type Depletion Layer

V

p-type compete and neither can other renewables.

Sooner or later solar energy will have to be stepped up because the solution is there.

It also doesn’t come with all the politics attached to oil. There need not be cartels of solar energy production, i.e. countries that have large reserves of fuel and dictate prices to the rest of the world. Sunlight is global.

Solar energy is several “orders of magnitude of

power higher than anything else available to the planet.

Hole Could you provide an insight on factors preventing growth in the solar energy industry?

Well the main reason is the cost. Currently, renewable energy costs more than oil. If we look specifically at solar energy, there are a couple of key issues. Firstly, the conversion efficiency of solar energy to electricity could be improved. However the main problem is energy storage. How do we store energy so that it can be used when it’s needed? The idea now is to generate fuels. Electrochemistry provides us with a technique to put (solar) energy in to generate hydrogen and oxygen i.e. fuel cells.

However, hydrogen gas is difficult to store and sell. Instead, distribution of energy in society is very suited for liquid fuels,

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for ease of transport. Much research is currently going into this area. For example, how solar energy can be utilised to reduce carbon dioxide to methanol or formic acid, which can be used as energy vectors.

Until better ways to transform solar energy into available fuels is found, it wont be available to society on a large scale.

Batteries can’t be made to supply cities.

On the other hand, it will work on the microscale. This is why you see solar panels on houses. Solar energy can also work where the grid penetration is not so strong, in isolated communities such as those found across Africa, South America and Asia. Whatever the local source of energy may be – tidal, wind or solar – it can be harnessed. This is where we can have an impact right now What areas of research is your group focused on?

My area of expertise is electrochemistry.

We have different research lines at the moment, all related to the problem of solar energy conversion and storage. One of the areas we are targeting involves new materials, based on earth abundant elements that could become active layers in solar panels. Silicon is very available but producing silicon solar panels is currently a very energetic process due to the strong silicon-oxygen bonds, which must first be broken. Our second zone of interest is in photovoltaic thin films. These absorb more light, so can be made thinner and are therefore less energy intensive to make. Another area relates to the electrochemistry of energy vectors. Mastering the catalysis involved in transforming available resources (such as carbon dioxide and water) to usable fuels, via solar power, will be key to the field.

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Where do you hope the future will take the field?

I would like to see increasing efforts and achievements across the world in terms of building renewable energy systems.

Another really important issue will be creating a circular society rather than one that produces waste and then simply disposes of that waste. For example, there is the Bristol initiative for buses powered by human waste. It’s just the beginning. We can save so much energy if we are efficient.

If we are clever about what we do, we’ll be able to do away with fossil fuels but this will probably not be in my lifetime. The problem is leadership, which is crucial.

Strong leaders can make solar energy possible by making bold political decisions.

Therefore I hope that politically, we take the right steps from now on.

Toby Benham

INTERVIEW

0 0 1 Climate Change, 110 Chaos and 101 Inexact Computing 000 Rosie Hayward 010 I 101 011 010 101 000 111 000 010 101 000 010 101 100 010 n February I had the opportunity to attend an excellent talk titled “Climate change, chaos and inexact computing” given by Professor Tim Palmer, a Royal Society Research Professor in Climate Physics from Oxford University. Many of the things he discussed are very relevant when it comes to the current discussion of environmental issues, such as climate.

Fortunately he agreed to answer some questions for Synapse about his research and opinions on our climate problem.

As a Professor of Physics at the University of Oxford, how did your research become focused around climate change?

I did a joint honours degree in maths and physics at Bristol, and then went on to do a PhD at Oxford in general relativity theory.

At the end of this I was undecided whether to accept a postdoc position in Stephen Hawking’s group, or to do something completely different with my life. I felt that the problem of quantising gravity was not going to be solved in the near future (I was right!) and on top of that I felt a need to use my expertise for something with a bit more societal relevance. A chance meeting with a famous climatologist persuaded me that this was a field worth looking at closely. I managed to persuade the Met Office that my maths/physics skills could be applied to weather/climate science

and from that I developed a career in the subject that has been very fulfilling. Much of my research has not been about climate change per se, but rather about the dynamics and predictability of the climate system.

You stated in your talk that predicting climate change is challenging, ‘not just because the climate system is chaotic, but because it is a large-dimensional dynamical system with scaledependent chaotic variability.’ Can you explain how the climate system consists of scale-dependent chaos and how this is modelled?

With climate change, we are dealing with a system that is naturally chaotic, i.e. has natural variability that is aperiodic. We are perturbing this system by systematically increasing atmospheric carbon dioxide concentration due to burning of fossil fuels. Because the climate system is chaotic, it makes it hard to separate out the natural variability from the effects of the forcing.

The degree of chaos gets larger as the scale of the natural variability gets smaller - for example, one can predict the motion of a mid-latitude weather system a few days into the future, but can only predict the evolution of a single cloud system a few hours into the future at best. This is relevant to how we model the climate system, as I describe in more detail below.

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0 1 0 0 1 0 1 1 0 0 1 0 1 0 1 0 1 0 1

010100100001010011000 010000000010101 110110111101100100010 010100100001010 011001011100010110000 110110111101100 010111101101100101101 We model this complexity using the laws of 011001011100010 physics. The Navier-Stokes 010101110011110001111 equations de010111101101100 scribe Newton’s Second Law110101010010111011110 (force=mass × 010101110011110 101110000001010111001 acceleration) for a continuum fluid like the 110101010010111 atmosphere or oceans. The 110111111011000101001 laws of thermo101110000001010 dynamics describe changes 001101000101110010001 in the thermal 110111111011000 structure of the atmosphere.110001010100011001000 However, 001101000101110 because the climate system 101011001000100000001 is a nonlinear 110001010100011 010001010010101101101 multi-scale system where different scales 101011001000100 101110100101100000101 interact, it is important to resolve as much 010001010010101 111000100110001111001 of the multi-scale detail as possible.

Ideally 101110100101100 110000100001011100011 we would like to include cloud scales in 111000100110001 100001110010100111010 our climate models. However, computers 110000100001011 110010111011100111000 aren’t big enough and so cloud systems 100001110010100 000111100001000000111 110010111011100 have to be represented approximately.

000111100001000 This is the biggest source of100011111000010000100 uncertainty in 111110110110011111010 100011111000010 climate change prediction.

100010101110110010101 111110110110011 110111101011101011001 100010101110110 What current efforts are being made to 010000010000011110101 110111101011101 overcome this challenge? Do you think 010111010000001101011 010000010000011 it is possible to overcome it in the time 100010000110101010100 010111010000001 frame climate scientists believe we have 100110011101101011011 100010000110101 left (before the temperature of the world 010111010100011101101 100110011101101 has varied by too great an amount)?

100110111100101011011 010111010100011 My own feeling is that we need to pool 111000001000011110101 100110111100101 national resources to build 010110111010110100010 international 111000001000011 100110110011110111101 climate prediction centres, so that climate 010110111010110 scientists have access to the011110001100001011011 very best 100110110011110 101101001001110000011 supercomputing hardware that is available.

011110001100001 However, there are political011101110000100110000 and techni101101001001110 100110111110011010101 cal obstacles to this. It is hard to predict 011101110000100 whether these obstacles can010110101100100010010 be overcome in The industry-standard for 100110111110011 010011111010110001000 the coming years. For the sake of society, I scientific computation is 64-bit precision 010110101100100 000101011101000110110 hope they can. (so called double precision). However, 010011111010110 011100101000101011011 representing variables with 64 bits puts 000101011101000 You mentioned the notion011100110111001000000 of inexact an enormous energy overhead on the 011100101000101 computing when referring011011111010101110101 to modelling computations. My group is now exploring 011100110111001 111100001111100100011 climate change - can you tell us about with computer scientists the possibility 011011111010101 110001101010000011100 what this is and how you believe this of computations where the level of 111100001111100 001110100101111100110 will help scientists with climate change precision is itself variable, and where 110001101010000 010011111100101011001 prediction? computations may not necessarily be fully 001110100101111 111000100100111010000 deterministic, but have a small amount of 010011111100101 Traditionally, computers provide 110101010000010001110 randomness (so 2.00 + 2.00 could equal 111000100100111 deterministic and precise computations.

011001110110010100001 4.00 most of the time, but 3.98 or 4.02 110101010000010 111001010000001111110 011001110110010 110110001011011011011 18 | SYNAPSE 111001010000001 111101001111010110101

INTERVIEW

1 0 0 1 0 1 1 0 0 1 0 1 0 0 1 1 0 0 1

0011111010110001111111110110100111 0 101100010100010011110011111100101 0000100011101000011101001010100011 001100001111101011000111111111011 0101001100101000011010101100110000 010001000010001110100001110100101 1 1101101011100011100111001101000101 011000010100110010100001101010110 1100101110010011000010100101111011 010110110110101110001110011100110 0100101111000110110110101000010011 000111110010111001001100001010010 0 1010000011011011001110001100010001 101111010010111100011011011010100 1011001011101000010101110001110000 011100101000001101101100111000110 1010110010100110000000010010100001 0 010100101100101110100001010111000 0100110100111110010101000100111000 001000101011001010011000000001001 1000001110010011100011110101110100 100100010011010011111001010100010 1 1101110011110101110000110010100111 000000100000111001001110001111010 1011010101101101110110100001100111 110110110111001111010111000011001 1101111100000001001101110101110100 0 000010101101010110110111011010000 1101101001100010011010011111100000 111100110111110000000100110111010 0111100010010010010000101001101100 110001110110100110001001101001111 0101101110011011111110010011100001 1 011101011110001001001001000010100 1001100001101100010000001100101101 011100010110111001101111111001001 0111011011000100000101010111011010 000011100110000110110001000000110 1 0001110111011001100100111010001001 000010011101101100010000010101011 1010101010100000001110010101010110 111101000111011101100110010011101 1011001001101111001101000100100000 0 001010101010101010000000111001010 1100101101101000100010001010000000 101100101100100110111100110100010 1001111100111001110111000001000000 111010110010110110100010001000101 0 0001010011010110011101100101011110 110101100111110011100111011100000 1001110101010101010011100110001101 101010000101001101011001110110010 1011000001111001000100011011110100 101101100111010101010101001110011 1 1101110110100111010000001011010011 110110101100000111100100010001101 1111001110100010100010111011101001 101101110111011010011101000000101 0111100000000110100001111001000001 0 111010111100111010001010001011101 1111110111111110101100000101001010 010001011110000000011010000111100 1001110000110111110011101100011010 011110111111011111111010110000010 1 1010111001000000010110010111011001 101101100111000011011111001110110 0000001010111101101100111100110110 000001101011100100000001011001011 1110001101010111100011100101000110 0 011000000000101011110110110011110 0101111111110101100000100001010000 101010111000110101011110001110010 0101101111101010110001011100100000 001001010111111111010110000010000 0001110010010101011110001101111110 1 000100010110111110101011000101110 1100011111010101000101110111010101 011011000111001001010101111000110 0010101110100010000101000011001110 101101110001111101010100010111011 0 1001100010100100011001000010100000 100000001010111010001000010100001 1110101000010000111010101000000101 111010100110001010010001100100001 0100111111110111000011110111111000 1 010001111010100001000011101010100 0101011001011101011110000010110111 001110010011111111011100001111011 1111110001011100100001010011001100 110011010101100101110101111000001 0 0101010100101011100101111100000011 101100111111000101110010000101001 0111011010100110000111010110110000 101000010101010010101110010111110 1010111100000111010010001000000100 000111011101101010011000011101011 1 0010101011010000110011000011110110 010000101011110000011101001000100 1100011101000000001110000111110100 these small-scale components with the conventional 64-bit representations.

On the other hand, the very large scales (such as jet streams) do need traditional 64-bit representations. Hence future supercomputers need to be hybrid systems comprising both deterministic, precise and stochastic imprecise chips. This notion could revolutionise the way scientists use big computers, with many applications in different areas of science.

Do you believe it is the responsibility of the scientific community to ensure the public are aware of climate change? If so, do you believe the responsibility extends to making sure the public have faith in the science presented?

occasionally). The advantage of such imprecision is that it allows computations to be performed with much smaller energy consumption. Put another way, for a given energy resource, one can potentially perform many more imprecise computations than traditional precise computations. This is where scale-dependent chaos comes in. As the evolution of cloud scales are so highly chaotic and hence very susceptible to noise, there is no point in representing

Yes I do. And I think the only way the public can have faith in the science presented is for the scientist to be policy neutral. For the most part, climate sceptics are the way they are because they have some political agenda. Similarly, some environmentalists may espouse green causes because it fits with their political philosophy. It is important for scientists to be completely neutral on these issues and to simply state as clearly as they can, what the science says. I myself try not to exaggerate the predictions of climate science and I always stress the uncertainties in the predictions. However, I also try to be clear that there is about a 50/50 chance of the Earth warming by as much as 5 °C in the next century, about the difference between the last ice age and today and an amount most would view as calamitous for society. Do we want to take this risk? This is not for me to say. However, if we want to reduce this risk (not so much for our sake, but for our children and their children’s sake), then we must cut our emissions of carbon dioxide into the atmosphere.

synapsebristol.blogspot.co.uk | 19 111111001010101101000011001100001 1001001001110101110101101110110101

ARTICLE

Atmospheric Aerosols Why do we need to understand their properties?

Aleksandra Marsh

Brightfield image of a single aerosol droplet.

A

n aerosol is defined as a suspension of solid particles or liquid droplets in a gas phase. Aerosols aren’t just found in pressurised containers and used as deodorants, they are also abundant in the atmosphere.

Why do we need to understand aerosol properties?

Atmospheric aerosols affect both human health and global climate and have a large size distribution (between 1 nanometre and 100 microns). Particulate matter less than 2.5 microns in diameter is of particular importance because it can be inhaled and penetrate deep in the respiratory system.

Aerosols impact climate because they affect the radiative balance of the atmosphere both directly and indirectly.

Aerosols can directly scatter or absorb incoming solar radiation or act as cloud condensation nuclei to indirectly effect the climate. Therefore, studies of the hygroscopic and optical properties of aerosols are essential to quantify their impact on climate and health.

20 | SYNAPSE

How are aerosols emitted into the atmosphere?

Atmospheric aerosols can be emitted directly as particulate matter or as volatile organic compounds (VOCs). Particulate matter and VOCs both come from natural and human sources. Natural sources of particulate matter come from volcanic ash or sandstorms while human sources include soot particles from combustion or biomass burning. VOCs are emitted by human activity from transport and industrial sources and also from natural sources such as leaves and the ocean.

Volatile organic compounds undergo oxidation in the atmosphere and go on to form aerosol droplets.

What happens to aerosols in the atmosphere?

Aerosols are incredibly dynamic and undergo changes in both size and composition in the atmosphere.

Compositional changes can be caused by particle-based reactions, or heterogeneous chemistry, where species in the gas phase react with the droplet. Furthermore,

aerosols also experience changes due to variations in relative humidity (RH) in the atmosphere. Relative humidity is a measure of the amount of water contained in the gas phase and therefore also in an aerosol droplet. The hygroscopic properties of an aerosol govern how much water an aerosol droplet can take up. Aerosols have variable atmospheric lifetimes and they can last in the atmosphere for anything from a few hours to days. Their size and thus atmospheric lifetime depends on their hygroscopicity, volatility and ability to undergo reactions.

How can we study aerosol properties?

Due to their very broad size range, aerosols are very challenging to sample in the environment. On aircraft, aerosols are sampled in impactors; however, aerosol composition on a sampler can change depending on how long the sample takes to be analysed. This has led to the development of in-situ measurements using mass spectrometers fitted into aircraft.

In the laboratory, aerosol properties are typically studied using a smog chamber to study an ensemble of particles. By contrast, the Bristol Aerosol Research Centre at the University of Bristol uses single particle techniques to analyse the physical properties of single aerosol droplets. Spectroscopy is used to assess particle size and composition.

Scattering

Absorption

D

e eas ecr

RH

Aerosol Optical Tweezers

Aerosol Optical Tweezers are an example of a single particle technique, where a laser beam is tightly focused through a microscope objective to create an optical trap, which can hold a single aerosol droplet.

The trapped particle, with a radius of 3 – 5 microns, is contained in a small chamber where the RH can be controlled. Particles can be imaged using brightfield microscopy.

Both stimulated and spontaneous Raman Spectroscopy is used to non-intrusively determine particle size and refractive index. A hygroscopicity experiment involves altering the RH of the chamber containing a trapped droplet and measuring the corresponding change to the size and refractive index. Using these data the optical properties, vapour pressure and the rate of water uptake can be determined.

Other single particle techniques include a Bessel beam, which allow particles of a smaller size to be trapped, and an electrodynamic balance, which allows the change in mass of charged particles to be measured as a function of time.

In conclusion, single particle techniques allow for accurate determination of the physical properties of aerosols.

Understanding of these fundamental properties is essential in order to predict the impact of aerosols in the atmosphere on human health and global climate.

synapsebristol.blogspot.co.uk | 21

ARTICLE

What can we learn about how the environment reacts to radiation?

Kieran McLaverty

O

n the morning of the 26th of April 1986, the western world was waking up to news of a catastrophic nuclear accident. Chernobyl, Russia’s biggest nuclear power plant, had suffered a major fire in one of its reactors after a testing exercise went wrong. Radioactive fallout was blown over a 100,000 km radius and the USSR immediately evacuated people living nearby.

Those who felt the full force of the radioactive fallout were the emergency crews that tended to the blast. Over the next few weeks, acute radiation led to the death of 28 firemen. However, the longterm effects of radiation would prove far more deadly, with diseases such as thyroid cancer being reported in up to 4000 people. The theory as to why radiation leads to mutations in our DNA is well established; more mysterious is the effect nuclear disasters have on the environment.

One of the closest towns to Chernobyl is Pripyat, which is now in modern day Ukraine. The once lively town of 43,000 people was virtually abandoned overnight.

30 years on and Pripyat has gradually been reclaimed by nature; trees break through

22 | SYNAPSE

the paving stones and packs of wolves make home the ruins of what used to be schools and hospitals. The government prohibits civilians from entering the town on the grounds that the surroundings are still too radioactive. Because of this, Pripyat has become the perfect environment for studying the effects of radiation.

Radiation causes damage by interacting with the copying processes of DNA. Essentially the way this works is that the four fundamental bases that make up DNA (Adenine, Thymine, Cytosine and Guanine) are disrupted by highly reactive molecules known as free radicals.

Free radicals occur in small amounts naturally, but are found in especially high concentrations in cells exposed to radiation. Any changes in the DNA sequence (or more specifically the order of A, T, G and C’s ) can lead to mutations.

Most mutations have no observable effect, while the ones that do can have serious consequences. BRCA1, BRCA2, and p53 are part of a family of hugely important tumour suppression genes – these usually stop the cells from multiplying

uncontrollably and cause the cells to die after a number of replications. Change in the sequence of these genes is the primary cause of cancer.

Cancer is by no means the only consequence of mutation. Mutations are the driving force of evolution – genes are very occasionally changed in a way that makes the proteins they code for more effective, which leads to their spread in a population.

Whether the higher number of mutations in environments like Chernobyl leads to a faster rate of evolution is an interesting question. A recent paper tried to draw comparisons between bird populations living in the nuclear fallout zones of Fukushima and Chernobyl.

The research team was able to identify 14 common species and compare their populations in varying areas of radioactivity. They measured the number of birds living in areas of 35 microsieverts of radiation (highly radioactive) and numbers living where radiation was lower, at 0.05 microsieverts.

As expected, the results indicated birds living both in Chernobyl and Fukushima experienced a drop in population at the 35 microsieverts level. More interestingly, the team recorded that the difference in drop of population number was twice as big in Fukushima as in Chernobyl. If we conclude from this that birds at Chernobyl are better

at dealing with radiation, we must ask ourselves what adaptations may have come about to minimize the effects of radiation.

A research team, Piechura J.R. et al, believe the answer lies in DNA repair mechanisms. Through exposing the bacteria Escherichia coli to lethal levels of radiation, then selecting the survivors, the team created a super-strain of radiation resistant bacteria. By comparing the genome of normal E.coli to that of the resistant phenotype, the team decided “mutations in the recA gene are prominent and contribute substantially to the acquired phenotype”. RecA is a bacterial enzyme that has a delete and paste function – snipping out one of the threads of double stranded DNA and replacing it.

The resistant strain recA was consistently different in structure, with three chemical changes leading to improved function.

RecA is a fundamental enzyme, with relatives in most organisms.

Cancer is the biggest cause of death in the UK. Through research such as this we can begin to understand exactly how organisms change to reduce the number of random mutations, which could one day shed light on a pre-emptive treatment for cancer.

synapsebristol.blogspot.co.uk | 23

ARTICLE

Why Do People Continue to Deny Climate Change?

Stefan Rollnick

B

arack Obama famously said that “we don’t have time for a meeting with the flat earth society”, and it’s good to know that the most powerful man in the world has both a sense of humour and a head that’s firmly screwed on. However our perception of the curvature of our planet isn’t quite as potentially life threatening as the belief that we can continue to pump carbon dioxide into our atmosphere without consequence.

Science denial has always been a dangerous thing; from the persecution of Galileo to the belief that HIV doesn’t cause AIDS, the potential for widespread death makes this an important issue. In that regard there are no issues quite as important as climate change, the effects of which are already becoming evident. Irregular and extreme weather patterns have the potential to kill hundreds of millions of innocent people, and I find it incredibly alarming that people are happy to settle this issue on rhetoric alone.

Some forms of climate change denial rhetoric are more common than others, with biblical rhetoric seeming

24 | SYNAPSE

alarmingly prevalent. For example, in 2015 a republican senator in the US denied the existence of climate change, citing the Bible as evidence. In a recent debate, he described people who believe that humans

“

even though 97% of climate scientists believe that human activity is responsible for most of the current global warming, approximately only 42% of the public agree.1

confined to the US. In the past, Australian PM Tony Abbott has famously denied the link between natural disasters and our changing climate, and has freely stripped down agreed international initiatives for reducing carbon emissions. This rejection of science is also abundant in public opinion, with 46% of Australians denying either that humans have a role to play in climate change (39%), or that climate change even exists at all (7%).2 There is clearly a huge disconnect between climate scientists and the rest of society. John Cook’s study on the “consensus gap” showed that even though 97% of climate scientists believe that human activity is responsible for most of the current global warming, only approximately 42% of the public agree.1 But what can be done to fight this? Well, research led initiatives like the Evidence Information Service (EIS) endorsed by the British Science Association aim to improve the accessibility of evidence to politicians by providing an easy to use database. This would certainly be a step in the right direction, but there needs to be a fundamental change in the public perception of science before we see any real change.

Changing public perception requires both education and engagement. This means that anyone studying science owes it to their subject, to every textbook they ever read and every documentary they ever watched to keep the flame of public curiosity alive. Science is a beautiful thing, and we need to show people that it’s nothing to be afraid of - only then will we see real change.

“

have the ability to change the earth’s climate as “arrogant”, despite the abundant scientific literature to the contrary.1 Nevertheless, the senator in question, Sen. Jim Inhofe, has been given the top environmental job in the Senate.

I for one find it extremely concerning that arguably the most powerful country in the western world has high ranking politicians that continue to refuse to believe in global warming. However, this is not just

1 2

John Cook et al 2013 Env. Res. Lett. 8 (2013) CSIRO Survey 2013 https://goo.gl/M189cQ

synapsebristol.blogspot.co.uk | 25

ARTICLE

Ecotourism

A different shade of green

Emma Eastcott

E

cotourism as a term appeals to the growing numbers of conscientious consumers; it conjures visions of harmony and sustainability, and of man at last working with nature, rather than against it. Sadly, for all its grandiose claims, many forget that the driving purpose behind large-scale tourism is not, in fact, hugging trees and saving gorillas. The truth is rather more sinister.

With the increased prevalence of cheap international flights and a larger disposable income, we now have to face the facts about the damage our time away causes. For many of our most precious environments, tourists swarm and overwhelm them, consuming vast amounts of water, energy and food, and leaving behind a trail of pollution, soil erosion and water contamination. It is clear that we need to reform the tourism industry to focus on sustainability, and this is what ecotourism aims to do.

By definition, ecotourism involves visiting fragile natural areas, with the intent of a low-impact approach that benefits local communities, enables sustainable development and political empowerment, and provides funds for conservation. On a small-scale it can be hugely successful.

26 | SYNAPSE

For example, the Iby’Iwacu Cultural Village in Northern Rwanda enables the local population to share their cultural heritage with visitors, and provides a direct incentive to conserve gorillas. This project has been a huge success; locals own 100% of the project, and ecotourism in the area has increased by 40%, generating a sustainable income base.

This has in turn encouraged local people to protect the gorilla population, and gorilla poaching has reduced by 60%.

So clearly, ecotourism can work.

However, we are now facing a more confusing problem: when is travel truly sustainable? Nowadays, travel companies regularly throw around popular “buzzwords” like “Eco-tourism” and “Natural Travel” to lure in a new and growing population of environmentally minded travellers. The issue with this is that it lures people into the common pitfall that commercial tourism is sustainable. While it is true that the travel industry has a vested interest in protecting the world’s natural resources for tourism purposes, it has other, greater, economical concerns. These often directly counter the core principals of the schemes they advertise, such as a focus on expanding tourism markets and lowering trade barriers. Because of this, it is hard to know truly how ‘green’ our travel is.

Especially in some of our most precious environments, self-proclaimed ‘ecotourism’ wreaks irreversible havoc on the very environments they claim to save. Nowhere is this clearer than in the Galapagos Islands. With a rapid growth in luxury and backpack travel, tourism to this fascinating archipelago has exploded. In 2007, 170,000 people visited the Galapagos, and despite the decline in visitors after the global financial crisis, the impacts are still vast. The demand for freshwater and food places pressure on local resources, and it is estimated that cars can run over 13,000 birds each year, including Darwin’s world-renowned finches. Even after preventing tourist access to over 90% of the islands, few spots have been left truly untouched by humans. The damage to the precious ecosystems that inspired Darwin’s revolutionary “Origin of Species” is devastating, with overfishing, pollution, and even trampling of precious plant life having massive implications. We have to question whether our visitation to these areas is really worth the terrible cost.

Perhaps it would be more important to drive a shift towards a long-term view of the natural world, rather than revelling in the fun of a “grab and grow” culture, then perhaps we could save our children the catastrophic consequences of the mounting environmental strains we place upon this remarkable Earth.

synapsebristol.blogspot.co.uk | 27

ARTICLE

Where are the

Bees?

Lydia Melville

T

ake heed of Sir Attenborough’s wise words because we are in grave danger. Imagine walking into a supermarket for your weekly shop and not seeing 80% of the products that are available today. This could happen if the rate of decline of pollinating insects, like honeybees, continues to drop.

So, why are we worried?

Honeybees, or Apis mellifera, are native to Europe, Africa and Western Asia and have provided humans with honey and beeswax for nutritional, medicinal and cosmetic value for centuries. However, recent years have seen beekeepers in Western countries reporting an unprecedented decline in honeybee populations.

The key cause of this decline seems to be a lack of both suitable habitats and flowering plants throughout the year, most likely due to increased mono-culturing of crops in the agricultural industry.

For example, rapeseed oil is the third largest crop produce of the UK after wheat and barley and it is now grown as a monoculture in the UK. Across the countryside, this bright yellow crop is harvested within a few weeks of blooming, leaving very little time for bees to harvest a whole winter’s worth of pollen.

28 | SYNAPSE

‘If we and the rest of the back-boned animals were to disappear overnight, the rest of the world would get on pretty well. But if the invertebrates were to disappear, the world’s ecosystems would collapse...’

Sir David Attenborough A secondary driver of the decline in insect pollinators is the increased use of pesticides and insecticides. Nicotinederived insecticides (neonicotinoids) are a new type of chemical which affects the central nervous system of insects, leaving them paralysed and quickly leading to death. Clothianidin is one example of a neonicotinoid that is thought to have been responsible for a huge decline in German bee numbers in 2008. Not only do such chemicals affect the insects, but they also remain in the soil, running into rivers and causing havoc across whole ecosystems.

The pollination work that bees do is worth around £165m a year to British agriculture. About a third of our foods rely on honeybee pollination, including apples, nuts, summer fruits (such as strawberries) and alfalfa for cattle farming. Certain crops yield up to 25%-40% more per harvest when efficiently pollinated by these hard-working insects. The crops we rely on and see as our fridge and cupboard basics could disappear forever if we don’t start to protect the bees.

‘To ‘bee’ or not to ‘bee’: The problems bees are facing One problem is that the products bees make are just becoming too popular.

With honey being seen as a healthier

sugar-alternative and rumours that local honey can provide a boost to your immune system, the demand for it in supermarkets and large food industries has risen dramatically in recent years.

This has caused a large surge in the beekeeping industry as both a way of producing commercial products and as a hobby. When asked by scientists from the University of Sussex, most farmers would be keen to have their own hives in order to help promote successful natural pollination. However, it seems that what bees really need more of is suitable flora and habitats, not more neighbours to compete with.

Bees are also facing an increase in diseases which are mostly transmitted from commercial bees on large farms to the wild, native species. Colony Collapse Disorder (CCD) is a serious threat to the health of honeybees and the economic stability of commercial beekeeping.

Scientists are still looking for an exact cause of CCD. Varroa mites for instance, a vector for parasite transmission in honey bees, have often been found in honey bee colonies that are affected by CCD. Varroa is an external parasite that lives exclusively on honeybees, feeding on their blood. As well as causing physical damage through feeding directly upon the bees and their larvae, they also act as a vector for a multitude of honeybee viruses.

It is not yet known if the Varroa mites are directly involved in causing CCD. It is thought that bee malnutrition and overcrowding, which cause increased migratory stress, are large factors in causing CCD. This is worsened by the increased use of monoculturing in agriculture, as

mentioned with rapeseed oil, since bees have to fly much greater distances to collect enough pollen. The Varroa mite is classed as endemic (a disease constantly present in a population in small case numbers) in England and Wales and widespread in Scotland and Northern Ireland.

The bee plea: What can we do?

An old aboriginal Australian proverb says that people should explain their problems to the bees, which were believed to have the potential to communicate with the aboriginal gods. ‘Tell it to the bees’ – this sweet and simple proverb emphasises just how majestic and influential bees are on this planet. But now, instead of telling our problems to the bees, we have to listen to theirs. So next time you’re feeling bored maybe spend some time planting lavender or marjoram plants for the bees, which from a two-year study performed by scientists at the University of Sussex, seem to be the bees’ favourites. What we need are more suitable habitats for bees before we introduce more bees themselves. Don’t feel guilty about lathering your porridge, toast or skin with honey products, just be aware of the bees working hard for it.

Finally, if you have a few spare seconds, please sign a petition from Greenpeace to save the bees at:

sos-bees.org/demand/

synapsebristol.blogspot.co.uk | 29

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Did you know?

In 2013, 85% of Iceland’s total energy consumption (electricity, transport etc.) was supplied from renewable sources (geothermal, hydropower and wind). The UK, albeit 200 times more populous, achieves an equivalent renewable share of just 5%.

Compared to Sweden’s 52%, Latvia’s 37% and Germany’s 12% among others, the UK ranks just 25th out of the 28 EU member states.

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100%

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