What about China?

Qu: Why are humans to blame for climate change? 

Every now and then I allow myself the luxury of believing one of those guilt-relieving theories that humans are not responsible for the rate at which the Earth’s climate is changing. There is no correlation between the increase in our GHG (green house gas) emissions and the 1.5-2C increase in temperature since the pre-industrial era. 

No, nothing to do with me; climate change is just part of the natural pattern of the current interglacial period – or it’s due to the Earth’s 40,000-year tilt, or its 23,000-year wobble – or can’t we blame Sunspot activity? 

Then I take a look around and face facts. Over the last 250 years, by digging up and burning coal, oil and natural gas, humans have put carbon, safely captured in the Earth’s sinks, back into the atmosphere. 

Now, as The Stern report showed in 2006, the concentration of carbon dioxide in the atmosphere exceeds the highest levels in the period for which data exists (covering the past 650,000 years). The increase of carbon dioxide causes global temperatures to rise, higher temperatures reduce the ability of the earth and oceans to absorb carbon dioxide, leaving more in the air. This creates a dangerous feedback: higher temperatures increase carbon dioxide concentrations and higher concentrations increase temperatures.

According to the Stern report greenhouse gas concentrations in the atmosphere at the time were 430ppmCO 2e (parts per million of carbon dioxide equivalent, which includes methane) and rising at 2ppm each year.  Above 450ppm CO2 global temperatures would have a 50% chance of rising to 2°C above pre-industrial levels and a 5% chance of reaching 3.5°C. 

This is no time to kid ourselves; we are firmly in the Anthropocene age: a new era in planetary history in which humans impact on the ecosphere. Yet some people are still in denial. Scientists are reported as being “astonished” by incidents such as the collapse of the Larson B ice shelf in the Antarctic or methane bubbling from permafrost. In reality, the scientific community has seen climate change coming for over 180 years (see the work of Joseph Fourier on gases in 1827). Source

In 1985 an international group of scientists got together with climate modelers (meeting as individuals so their report was unconstrained by commercial or political pressure), they predicted, “substantial warming” that was unambiguously “attributable to human activities”. No ifs, no buts, no maybes. This meeting led to the Rio Earth Summit in 1992, then to Kyoto in 1997. 

At the December 2007 UN Climate Change Conference in Bali the last few countries finally agreed that human activity is responsible for global warming. This conclusion has been reached despite the best efforts of Big Oil, which has given massive grants to any scientist or pseudo-scientist who would cast a few doubts.  It had taken politicians 22 years to catch up with scientists.

The question now is; if humans have caused global warming is it too late to do something about it? Carbon dioxide takes time to permeate the atmosphere and cause global warming, so present temperatures are the result of 30-year- old emissions. Today’s emissions will therefore impact on temperatures during the coming 30 years. 

Thankfully politicians are beginning to take climate change seriously, the recent increase in carbon reduction goals from 60% to 80% by 2050 shows that the UK government at least, is finally realizing the urgency. Another leap forward is an amendment to the Energy Bill meaning that individuals who contribute renewable energy to the grid will be financially rewarded. This energy scheme has been successful in Germany and is a step towards empowering individuals to create a future that is not dependant on oil. 

All these steps forward have been triggered by groups of individuals who have refused to bury their heads and have instead campaigned for change. We can make a difference and now is the time to do it. 

Bethan

Links to souces: 

James Bruges: The Big Earth Book 

QU: Hundreds of thousands, if not millions, of car tyres are worn down on roads every year. What effect do the tons of rubber dust have on the Earth and on us?

Everyone knows that cars are bad for the environment – of course they are – we love to bemoan the rate at which they consume our rapidly declining stocks of fossil fuels. It’s rare, however, that you find people blaming the tyres, normally we only notice them when one is looking a little flat. Perhaps this needs to change; research indicates that pollution from tyre dust is linked to an expanding range of health problems including allergies, asthma and even heart disease! 

The problem is that what goes into a tyre eventually comes out as the tread wears down. And what goes in? The list of ingredients is not as simple as rubber from a rubber tree! To form the rubber into hard-wearing vehicle tyres, an extensive range of chemicals including xylene, benzene, petroleum naphtha, chlorinated solvents, polycyclic aromatic hydrocarbons, anthracene, phenanthrene, phenols, amines, oil, acids and alkalis, polychlorinated biphenyls, halogenated cyanoalkanes, processing aids, and plasticisers. Tyre processing also involves several heavy metals including zinc, cadmium, lead, chromium and copper.

Argh! It gets worse; as you drive, tiny fragments of this cocktail of ingredients break off creating a particularly insidious form of air pollution known as tyre dust or particulate matter.

Until recently scientists working for the Environmental Protection Agency (EPA) thought that tyre dust didn’t present a threat to humans because the particles are too small to enter our lungs. But in the last decade studies have shown that about 60 per cent of the fragments can enter the very deepest parts of the human lung and cause damage. In areas of high traffic tyre dust can cause asthmatic attacks and pose a serious threat to the elderly, babies and young children. More worryingly tyre dust has now been linked to heart disease and diabetes. 

The impact of tyre dust on human health is undeniable. So it is particularly frustrating that there appears to be no immediate answer to, or recognition of the problem. In fact relatively little data exists to quantify the emission rates, size, distribution and composition of particulates from tyre wear. When government think-tanks talk about tyres, they generally focus on waste disposal, this is undoubtedly important, but clearly its scope is woefully inadequate. 

It’s time that the bigger picture of tyre lifecycles is examined so we can begin to reduce their impact on health and environment. In the meantime you can reduce your car’s contribution to the dust by ensuring it’s tyres are inflated to the proper level and correctly balanced, keeping your speed down and making sure you don’t overload it. Even better you can leave the car in the garage and hop on your bike – wearing your safety dusk mask of course!

Bethan

Sources:
The Ecologist
Green Living Tips

QU: What are the environmental impacts of the many BBQ’s held throughout the summer? 

Summer? What summer? Thank goodness that autumn has arrived and we no longer have to live with the disappointment of grey and drizzling days. Roll on frosty mornings and ripening orchards… Sorry, I digress, despite the highest rainfall since records began this summer many people still stoically pulled their trusty bbqs from the back of the garage to enjoy their traditional if slightly soggy, carbonized sausages. 

During the summer at the slightest hint of a dry evening people all over the country flocked to the shops to buy the necessary bbq paraphernalia; meat, salads, charcoal, fire lighters, dousing liquids, throw-away one-time-use barbeques and more. And why not – it’s a chance to invite the neighbours over to admire your garden while you fumigate theirs. As we race to sear the salmonella from the chicken before the last rays of sunshine fade the environmental impact rarely crosses our minds. Perhaps it should; when you add up all the BBQ’s taking place across the globe the effect is greater than you might think. 

Let’s start with the actual cooking device; throwaway bbqs are a total waste of material and an extra burden on already overtaxed rubbish disposal systems – you wouldn’t buy throwaway saucepans would you? 

But permanent bbqs are expensive I hear you cry. Indeed they are – or can be. Cheap bbqs made in Asia are increasingly popular but the air freight makes them an environmental no-no. Have you ever tried to buy a bbq made in the UK? I have and it’s a bit of a challenge, the closest manufacturer I could find was in Germany, which is better than China in terms of “bbq miles” but not ideal. The best thing is to make your own. 

Take the grill out of our oven and place it over a base built of bricks. The base can stay till the next use and the grill returns to it’s rightful place at the end of the feast. You can even take your grill camping with you and build an impromptu BBQ on the beach with the help of a few large stones. 

Now that’s sorted let’s consider your fuel. To get that smoky bbq taste most people opt for charcoal – this might be good for flavour but not it’s not so good for forests: 97 percent of the grilling charcoal consumed in Britain comes from non-sustainable forests. 

On top of that, briquettes, which are the most popular form of grilling charcoal, are often doused in petroleum solvents. 

“Charcoal grills and lighter fluid contribute to ground-level ozone, which is produced when nitrogen oxides and volatile organic chemicals [VOCs] combine in hot weather conditions.” says Ana Gomez, of the Pennsylvania Department of Environmental Protection. (source) Not only is it bad for our respiratory system, it also irritates the eyes is generally unpleasant for anyone in the area. 

You can buy British charcoal that’s made from properly managed native woodland, it’s more expensive but well worth it. Eco-charcoal is available at Tesco, Sainsbury’s, B&Q and some Co-Op stores (source) . Or give give the forests a break and use natural gas instead, though as natural gas is tricky to extract it is more expensive to buy. 

You could avoid emissions altogether by using a solar stove, though you’d have to be really lucky with the weather! It cooks slower but as it’s flameless it also eliminates the carcinogens formed when meats are grilled or broiled at extremely high temperatures or when fat from meat, fish, or poultry drips onto hot coals and deposits back onto the food via smoke. 

Which brings me nicely onto the subject of what’s cooking on your grill. A report by Friends of the Earth highlights the deforestation of the rainforests for intensive production of palm oil and soy, which is used in the chicken, beef burgers, and veggie burgers.

So, in short, build your own bbq, choose your fuel wisely, keep processed meats off the menu and, weather permitting, you can still enjoy your annual bbq. 

Bethan

Qu: Would it be possible to put waste, i.e. bio-degradable rubbish and sewage into an air-tight container, let it produce methane gas, siphon it off to cook with and power gas-fired central heating, filter off the water, and be left with compost to put on gardens?

Yes – very possible, in fact it’s already being done. It’s called Anaerobic Digestion and the process is widely used to treat wastewater sludges and organic wastes. Anaerobic digestion can reduce the emission of harmful landfill gases into the atmosphere and is a renewable energy source because the process produces a methane and carbon dioxide rich biogas suitable for energy production. Also, as the question suggests, the nutrient-rich solids left after digestion can be used as fertiliser.

So why isn’t this process used everywhere? Anaerobic digesters require a high level of technical expertise to maintain as careful control of the digestion temperature, pH, quality of input and loading rates is crucial. Because of these complexities, despite being recognised by United Nations Development Programme as one of the most useful decentralised sources of energy supply and being less expensive to run than large powerplants, anaerobic digesters are not widely used in industry. (source)

Anaerobic Bioreactors, a type of landfill, can also transform decomposing material into an energy source. By removing oxygen and pumping lechtate (water which has collected waste products from the decomposing matter) and other liquids around the bioreactor the waste produces methane, which can be collected and used instead of fossil fuels. (source)

Perhaps the most exciting and accessible use of the anaerobic production of methane from plant waste is the ‘pyrolysis unit’ – invented for domestic use in India by Ravi Kumar. A family collects waste plants, dries then and puts them into the unit’s circular casing. This casing is sealed to stop oxygen combining with CO2. A small fire is started in the central void; this heats up the plants and causes them to emit gases through small holes in the casing. The gases ignite and burn for long enough to cook dinner (about an hour). Then, brilliantly, the remaining charcoal can be raked out and used as fertiliser – what’s more the soil’s subsequent ability to lock in carbon dioxide also increases. (James Bruges – What About China?- p19)

Hope that helps, 

Bethan

Qu: Having read your answer on the effect of patio heaters (last bastion of the smoker) on global warming I wondered what the effect of the 6 billion cigarettes smoked annually around the world has on the global environment?

Oh dear, this answer sure ‘ain’t pretty. Now I’m really going to have to disown all my still-fag-smoking now ex-mates. 

Let the anti-ciggie tirade begin! Starting at the end and working backwards seems appropriate as cigarettes are most obviously harmful to the environment when discarded, marring the view as they lie scattered beneath the fore mentioned patio heaters. 

Sadly, cigarette butts are most often than not thrown to the floor and left as litter.  It is estimated that over 4.5 trillion cigarette butts are irresponsibly disposed of annually, making them the most littered item in the world. 

There seems to be a general consensus (ask any smoker) that cigarettes are bio-degradable over a 25 year period– however this figure is debatable and some experts doubt that the filters will ever degrade. Even as they break down cigarettes are harmful as they release the 4,000 chemicals that they contain, contaminating the soil or rivers, lakes and ocean that they are washed into. Wildlife is also affected as these toxins enter the food chain and many creatures fatally consume the indigestible fibers. Cigarette packaging is often littered as well; in the UK alone, each day, 122 tonnes of cigarette related debris is thrown out.

As they are smoked they are an environmental nuisance, as 90% of their smoke gets into the atmosphere, adding to air pollution (remember the days that you couldn’t even see to the bar when you walked into your local) and having a negative impact on the health of anyone nearby. 

If you think all that is bad then wait till you hear about the environmental impact of cigarettes. It is estimated that up to 200 000 hectares, usually in the developing world, are cleared to make room for tobacco farming every year. The sensitive tobacco plants are then treated with a nasty cocktail of fertilizers, pesticides and herbicides to protect them from insects and disease. Tobacco farms are often by villages and, when the chemicals inevitably leak into the soil, they begin to poison the waterways, ecological systems, crops, and livestock in the surrounding communities.  Tobacco uses more nutrients than several other crops, and this quickly degrades the surrounding soil.  It is also believed that the toxic chemicals may indirectly cause the development of pesticide-resistant mosquitoes and flies.      

Living by a tobacco farm is no fun then, but this gets a whole lot worse if you’re unlucky enough to be one of the workers harvesting the plants. When the wet leaves are picked nicotine can be absorbed through the skin resulting in nicotine poisoning.  This ‘green tobacco sickness’ causes dizziness, nausea, vomiting and breathing difficulties and affects 41% of workers every season. 

On top of the land clearance for tobacco planting we must also take into account the trees that are felled to process the leaves and to produce the wrapping and packaging for cigarettes. Nearly one hectare of forest is needed to dry every hectare of tobacco meaning that over 600 million trees are destroyed annually for this purpose. On top of that six kilometers of paper is used per hour by the machines that roll and package cigarettes! 

And then there is tobacco’s contribution to world hunger. According to Dr Judith MacKay, Director of the Asian Consultancy on Tobacco Control in Hong Kong, tobacco’s “minor” use of land denies 10 to 20 million people of food. 

Anyone fancy popping out for a smoke? Didn’t think so!

Bethan

Thanks to these links for the above information.

http://www.smokefreecalgary.com/bins/content_page.asp?cid=3-119&lang=1 
http://www.litterbutt.com/
http://?www.aadac.com/87_447.asp?
http://tobaccofreekids.org/campaign/global/pdf/ag2.pdf
http://?www.hpb.gov.sg/hpb/default.asp?pg_id=865&aid=105
http://?www.cigarettelitter.org
http://www.ci.berkeley.ca.us/publichealth/tobacco/environ.html?
http://www.ash.org.uk/html/international/html/environment.html?http://www.longwood.edu/cleanva/cigarettelitterhome.html

Qu: What’s your stance on energy saving light bulbs? I’ve heard several reports that they contain mercury and can be dangerous.

The media had a field day at the end of last year with some serious scaremongering regarding the dangers of energy-saving bulbs (CFL’s).

It all began when The Daily Mail picked up on a report by the Environment agency calling for a public awareness campaign to explain that the packaging of energy-efficient lighting contains small amounts of potentially toxic mercury and should therefore be disposed of with care.

The Mail ran a typically hysterical piece headlined “An energy saving bulb has gone – evacuate the room now!”

The general thrust of the article being, ‘energy-saving light bulbs are so dangerous that everyone must leave the room for at least 15 minutes if one falls to the floor and breaks.’

This is, of course, an exaggeration of the facts. Toxicologist Dr. David Ray, from the University of Nottingham, told the BBC that 6-8mg of mercury is present in a typical low-energy bulb. A pretty small amount considering thermometers, which we happily stick in our mouths, contain about 3 grams of the stuff.

Dr. Ray concludes that a smashed bulb causes little danger – but warns that this increases proportionately to consistent exposure and greater numbers of smashed bulbs. DEFRA also played down the threat to health, saying; ‘No amount of mercury is good for you, but the very small amount contained in a single modern CFL is unlikely to cause any harm, even if the lamp should be broken,’

(It’s also worth noting that strip lighting has always contained mercury – yet no-one seems to be complaining about that!)

The Mail went on to finger energy-saving bulbs as a potential source of cancer following a report by British Association of Dermatologists (BAD).

In this next distortion of the facts they claim that the ‘new’ lights (they’ve actually been around for over 30 years) “can trigger migraines, as well as dizziness, loss of focus and discomfort.” However the article goes on to say that these symptoms would only affect people already suffering from certain conditions (like epilepsy and photosensitivity). Dr Colin Holden from B.A.D. explains that people suffering from photosensitive skin conditions should be allowed to continue to use daylight (tungsten) bulbs to prevent “photosensitive eruptions ranging from disabling eczema-like reactions, to light sensitivities that can lead to skin cancer.”

Fine, those with a medical condition would obviously be prescribed the old bulbs, but that shouldn’t stop everyone else switching to CFL’s.

The real concern, the one that started this debate in the first place, is the environmental impact of disposing of the energy-saving bulbs. The Environment Agency’s call for a public information campaign acknowledges a need for greater awareness before tungsten bulbs are completely phased out. Careful disposal of the energy-saving bulbs will prevent the mercury content being released into the atmosphere. Thankfully more and more places now provide the facilities for you to drop off your used bulbs to be disposed of safely, including council refuse tips and some bulb retailers (Ikea, DIY stores etc.) and this service will become more widespread as CLF bulbs become more popular.

Besides, it’s reported that, even if everyone just threw their CFL light bulbs into the main rubbish to go to landfill, the amount of mercury entering the environment would still be less than that which currently enters the environment as a result of the production of the electricity needed to power all the traditional lightbulbs. Besides, CFL bulbs last far longer than traditional ones so there will be far less of them to throw away (source). So, no excuses, off you pop to the shops to buy your new bulbs…

Bethan

One of the key issues at the recent G8 summit was the global increase in the cost of food. As discussed previously, the rising price of staple foods has been linked to the increased cost of oil, which has caused land previously used for food crops to be turned over to crops for bio-fuels.

At the summit in Japan, the World Bank President Robert Zoellick highlighted the growing food shortage and urged the US and ‘rich countries’ in the EU to reform their bio-fuels policies and concentrate on food production. All well and good but it’s hard to believe all this talk is going do much to curb the rate at which your weekly shopping bill is creeping up, especially considering the frequency of missed G8 targets.

But we’re not as helpless as we imagine, the average consumer might not be able to dictate how farmers use their land but we can make sensible choices when it comes to dinner time. You’d think, with the increased prices, that people would be making an effort to make each meal count, but a recent survey estimates the average UK household throws away £8 of leftovers a week and each year in the UK as a whole wastes 4 million tonnes of food. People are spending about 9% of their income on food, with poorer households forking out up to 15% of theirs on staple foods such as milk, eggs and bread – foods that have been hit hardest by price increases in recent months.

This week Gordon Brown urged Britons to stop wasting food and to avoid making unnecessary purchases. But it’s not just the consumers who need to change their habits, the government might be more successful in reducing waste if they tackled supermarkets directly. The Liberal Democrats environment spokesman Steve Webb, blamed the governments “cosy” relationship with supermarkets for their failure to change policies which make it harder for householders to avoid food waste: “They refuse to stock small portions, which are essential for the growing number of one-person households, and offer too many buy-one-get-one-free deals on perishable goods.” Supermarkets also account for a large percentage of waste and throw away large quantities of edible food through poor stock management.

So, what can you do? Try planning your evening meals for the week and using up tins you’ve shoved to the back of the cupboard. Making extra in the evening means you take care of lunch the next day too – and this saves on energy, as you won’t be turning the cooker on again. Cooking for more people always works out more economically so offer to cook for your flatmates or friends and get them to return the favour another night. You can also try avoiding supermarkets; they might seem cheaper at first but in the long term it means smaller shops can’t survive or have to put their prices up further. If you do have to go to the supermarket write a list and stick to it – don’t be tempted by offers which will leave you with a fridge full of out of date food.

Bethan

Qu: To what extent will reductions in carbon emissions in the UK as a result of greener cleaner technologies be compromised by predicted world population growth of (according to a study by the U.N) a further 2.5 billion souls by the 2050?

Good question, and one that seems to be ignored in the general media hype surrounding climate change. Everywhere you look media channels and big business alike are out to persuade individuals to ‘do their bit’ by reducing their personal CO2 emissions. All well and good and as an empowering strategy to positively impact climate change but one that starts to look more like a convenient marketing strategy when you consider predicted population growth. The sad fact is that unless we do something drastic out-of-control population growth will wipe out the gains by even the most ambitious conservation and recycling schemes.

As John Feeney, writing for The Guardian, points out: “To avert catastrophe, we need to reduce both factors in the equation: our numbers and per person consumption.”

Yet the population issue is routinely overlooked. Feeney goes on to highlight the work of the Global Footprint Network (GFN), which tells us that, given the current population, each person has an allowance of just under 1.8 gha (global hectares of biologically productive land and sea) to maintain a sustainable global footprint. Given our current average of 2.2 gha per person we are exceeding the earth’s limits by 25%.

The GFN calculate that a drop in consumption to 1.8gha per person in the UK would involve a reduction in consumption to match level of Uzbekistan. Globally this would mean radically raising or reducing the living standards of some countries not a very realistic prospect.

?And these stats don’t take into consideration the UN’s projected increase in population of 40% by the middle of next Century. Compensating for the rise would mean shrinking the global footprint to under 1.3 gha, roughly the level of Guatemala or Nigeria. Again – not a vision of the future I’d put my money on being realized.

Although it is important to do your best to minimize personal contribution to global consumption it’s equally useful to be aware of the issues involved. In the face of the UN’s predictions population is a very real factor in the climate change debate and should be treated as such by governments and the media.

Bethan

Further reading & useful sites:

The Optimum Population Trust
Sustainable Population blog

Qu: If turning off appliances, recycling etc. are just a drop in the ocean; is there any point doing them at all?

With all the media hype, the threat of peak oil and messages of impending catastrophe for the planet, I don’t blame you for feeling over faced. Ultimately global change will happen quickest if instigated by global leaders. Once out of the ground fossil fuels will be used and harmful pollutants emitted. Politicians must devise and implement policies that reduce the amount of coal, gas and oil extracted within, or imported into a country. The sad truth is that if leaders don’t control the amount of fossil fuels at source all our attempts to reduce emissions in a hundred little ways make a very small impact on the overall situation.

However, that doesn’t mean your efforts are useless. Every little does help, so keep up your recycling, turn of those appliance and encourage others to do the same. You can also use your vote to influence the way the government prioritises. Politicians won’t change unless the public puts pressure on them. If you don’t then it’s left to corporate lobbyists, who can twist legislation to ensure that corporate interests are served. As James Bruges writes in What About China? A new wave of thinking suggests that the solution must involve individuals.The atmosphere does not belong to corporations – not even to governments or countries. We all, as individuals, have an equal right to its life-maintaining properties.

Instead of getting demoralized find out who your local MP is and urge then to put a cap on the use of fossil fuels. Get inspired about what you can do by learning more about the transition town movement, where communities are successfully working together to find a post-carbon way of living.

Bethan

Qu: I’ve heard that patio heaters are worse than trans-Atlantic flight for carbon emissions. Can this be true?

Hmmm… I’ve heard this one before, it’s the kind of gloomy end-of-the-world rumour that people like to pontificate as they light up outside the pub under one of the offending appliances!

Patio heaters are obviously so wasteful, in that their job is essentially to heat the open air (!), that they are often held up as an example of societies improvident tendencies. It’s true; they are a complete waste of energy, but as a nation we have many much more wasteful habits which we choose to overlook so a bit of perspective is needed to answer the question.

The average UK patio heater has a consumption of 8.9 kilowatts (kw). That’s quite a lot for a ‘non-essential appliance’. In fact a patio heater turned on for an hour uses enough power to boil a kettle from cold 80 times. And 8.9kw is the average, but most of the, the ones smokers huddle under in pub gardens, emit 12kw or more – there are plenty of 15kw patio heaters out there.

They use bottled LPG (propane) for fuel and for every hour of use a 12kw heater emits 2.6Kg of CO2. (source)

So, how does that compare to the CO2 from a transatlantic flight? Well there’s quite a lot of variance depending on the carbon calculator you choose to use as the assumptions behind them differ – which isn’t very reassuring! For the sake of this question I’ve taken a middle of the road figure provided by CO2balance. This company quotes a distance of approx. 5586 km (return from London Heathrow to New York) and CO2 emissions of 2.54 tCO2 for one passenger.

Your flight would take approximately 7 hours, during which you would produce approx. 2540 kg CO2. Running your 12kw patio heater for the same amount of time will produce 18.2kg. So if you use time as a comparison your flight is much worse.

The answer really depends on your patio heater usage and how many flights you take. The Market Transformation Programme (MTP) who supply government stats report state that use of patio heaters by individuals is relatively low. It’s pubs and restaurants that make the most impact and with the smoking ban increasing the demand for cosy outdoor things are set to get worse.

Before the introduction of the smoking ban, MTP estimated 2006 emissions from heaters at 20.3 ktCO2. They’ve predicted that in the wake of the ban emissions could be between 141 and 282 ktCO2 annually. (yes, that’s KILO TONS). (source)

However before you go vigilante and start persecuting all those pubs trying to heat the world, it’s worth looking at the wider picture. The UK’s total production of CO2 in 2006, according to DEFRA, was 556.5 million tonnes, meaning that the patio heater’s share is negligible, even at the upper end of the MTP’s estimates. Passenger cars, on the other hand, accounted for a chunky 68.7 million tonnes and air travel is increasing every year – and being actively encouraged with the opening of the new Heathrow terminal.

My advice is to boycott the pubs that use the offending appliances (put a jumper if you want to be warm while you smoke), then start finding holiday destinations you can drive to – or even better, reach by train.

Bethan