By Lisa Hodge
Climate change is a high on the global agenda and aviation is accused of being a major contributor.
Global warming is the biggest threat to the planet today, according to environmental experts and campaigners. A worldwide crisis that requires a man-made solution.
Essentially the Earth is heating up as a direct result of gases produced from vehicles, power plants, deforestation, and other sources which are building up in the atmosphere, acting like a thick blanket over our planet.
If airlines want to fly more, they will have to pay for emissions reductions in other industries — so overall carbon dioxide in the atmosphere will not rise.
Because of this, during the 20th century the impact of our daily lives has resulted in an increase of around one degree Fahrenheit on average global temperatures and aviation has played its part.
On a fundamental level international aviation contributes to climate change through different aircraft emissions, such as carbon dioxide, water vapour emissions, contrails or indirectly through nitrogen oxides.
Add to this the fact that planes fly in the upper atmosphere where the effects of carbon pollution are increased three-fold.
To put this into perspective; one short-haul flight produces roughly the same amount of the global warming gas as would be produced by driving a 1.4 litre car around for three months.
Despite efforts from the airline industry to improve aircraft technology and efficiency to reduce greenhouse gas emissions (GHG), it has not been sufficient to compensate for the rapid growth of global air traffic which has increased by around 50% in the last decade.
Obviously the increase in air traffic has led to a rise in the amount of fuel consumed and since 1990, carbon emissions from aviation have increased by 87% - accounting for around 3.5% of the total human contribution to climate change.
In foresight of this, the global carbon trading scheme was set up in 1988 to give each country the choice between paying to cover the costs of their emissions or paying someone else to cut their pollution.
But because of the rapid growth in air traffic the 2005 the Kyoto Treaty was introduced, which stipulated that industrialised countries would have to cut their emissions from their 1990 levels by 5.2% between 2008 and 2012.
Scientists have developed this theory further by suggesting that ‘personal carbon trading' should be introduced, whereby individuals are each given a carbon quota. A frequent flyer would be able to "buy airspace" from someone who has a low energy-use lifestyle.
According to some economists the scheme could have a positive impact on poorer countries and people living in poverty who would have the option of "selling" their carbon quota.
Carbon trading sets a cap on emissions from the whole economy, and individual firms are given allowances of permitted emissions. If they exceed their allowance, they must cut their level or buy extra allowances from other organisations which aren't using their allocated levels.
Through its participation in the UK's voluntary carbon trading scheme, British Airways (BA) has reduced its contribution to UK emissions by 23%. BA's Andy Kershaw says: "By participating in the UK scheme we have demonstrated that trading can be applied to aircraft emissions. Plus, BA has gained practical experience for the future.
"We have played a leading role for the last eight years in calling for airlines to be included in global carbon trading, campaigning publicly and lobbying the UK government and the European Union.
The campaigning has led directly to the European Commission legislating for the EU carbon trading scheme to include aviation from 2011, but BA is calling for the scheme to come into effect earlier.
Along with its recycling schemes, BA has saved over 60,000 tonnes of CO2 in just two years by flying shorter routes over China and Brazil, refining landing and take off procedures and fitting new seats to A320 aircraft.
Under the EU's carbon trading scheme airlines will be obligated to pay for exceeding their current level of emissions. All flights within Europe will come under the jurisdiction of the Emissions Trading Scheme by 2011 and from 2012 the scheme would be expanded to include all international flights that arrive at or depart from any EU airport.
Airlines would be issued with pollution permits - those that cut emissions would be able to sell their surplus while an airline that increased its emissions would have to buy more permits.
But problems have already arisen with the US questioning whether it would be legal within global trading rules to force airlines flying into the EU to take part in the scheme.
Some reports have even suggested some US airlines are considering legal action to overturn the decision.
To date, the aviation sector has not been forced to do much to address climate change, but as the pressure mounts from activists and environmentalists, the industry is facing more challenges in terms of business growth.
The imminent expansion of one of the world's major airports - Heathrow - has caused major controversy amongst green campaigners. Supporters of the expansion say a third runway is fundamental to maintaining Heathrow as Britain's gateway to the global economy as well as playing a vital role in bringing in billions of dollars through exports and supporting hundreds of thousands of jobs.
But those opposed to the plans argue aviation is the fastest growing contributor of carbon emissions and an expansion of Heathrow only undermines global efforts to tackle climate change.
British Airways are the flag carrier for the UK and also one of the major supporters of the expansion plans.
British Airways CEO Willie Walsh, says a balance between economic growth and environmental responsibility is possible.
He says: "We are committed to ensuring that growth is sustainable. By the time a third runway becomes operational, aviation emissions will have been capped by the EU for several years.
"If airlines want to fly more, they will have to pay for emissions reductions in other industries - so overall carbon dioxide in the atmosphere will not rise because of a third runway.
But environmental activists and some political groups still argue not enough is being done by airline companies to reduce carbon emissions, the UK Green Party even labelled Heathrow's expansion project "an attack on London".
A highly dubious economic case is being constructed to justify a catastrophic impact on people's environment, now and in the very near future.
"Air pollution kills, persistent noise increases risk of depression, and climate change is already destroying, and taking, hundreds of thousands of lives across the globe," says Sian Berry from the Green Party. But airlines are fighting back.
Through the introduction of ‘climate friendly' schemes, the industry collectively claims to be doing its bit to reduce its impact on climate change - and not because it has to, says Iain Burns, Vice President of Corporate Communications at Etihad Airways, because it wants to.
"The environment is obviously crucial but part of a wider picture of Corporate and Social Responsibility (CSR)," he says.
"Carbon emissions represent 2% of all global emissions but I think we recognise that while that's a very low number, we can't sit back and rest on laurels. We will look to reduce this figure as part of our strategy.
The Abu Dhabi-based company is one of the major airlines hoping to lead the way in cutting carbon emissions by getting their passengers involved. Burns says: "In terms of specifics we are looking at ways we can improve flight efficiency.
"We currently have an online facility where passengers can trade in their frequent flyer miles and off-set them for carbon emissions. At one time if you were a frequent flyer and you joined our Etihad Guest facility you would rack up points and miles which could then be traded for taking your family on holiday.
"Now we are finding there's a genuine number of customers who are saying they want to give something back to the environment and this scheme allows them to do that.
But Burns says being a Gulf-based airline has meant Etihad has faced more challenges than most.
"We are still a relatively new airline and the issues are a new phenomenon in this part of the world. But something that is important to us so it's something we will get more into as we become more sophisticated. We are looking at what can we do as an airline and what can we do as the national airline of Abu Dhabi.
"The last thing we want to do is for this to be a knee-jerk reaction or to turn this in to some kind of PR bolt-on. It's a much wider issue than just the environment, it's about Corporate and Social Responsibility.
Dubai-based carrier Emirates Airlines is also embracing its social responsibility. Having already introduced a ‘weight reduction programme to cut carbon omissions, it has recently invested in more fuel-efficient fleet - a clear indication of a serious attempt to help solve a very serious problem.
A spokesman for Emirates said: "Emirates has an ongoing programme to reduce weight onboard, and this extends right across our operation, including areas such as catering, engineering, in-flight entertainment and beyond.
"We also work closely with airframe manufacturers to optimise the design of aircraft we purchase, ensuring that there is minimal excess weight on board.
"In addition to reducing onboard weight, we also undertake a wide range of other measures to lower our fuel burn, and thereby reduce the environmental impact of our operations.
These include investing in a modern, fuel-efficient fleet - the Boeing 777, the Airbus A380 and A350 - as well as pursuing the development of more fuel efficient routings, and working with various Air Traffic Control authorities to improve air traffic flow management.