Flying beyond our means – air travel and the environment

Box 3 | Saving our skies – what can we do?

There is, of course, a simple way to reduce the amount of greenhouse gases produced by flying, and that's for people to fly less.

That's not a desirable solution from the aviation industry's point of view, but the idea is already on people's radar.

Conferencing by phone, video or web-casting is one way that companies are looking to reduce the time, cost, and inconvenience of having staff fly interstate or overseas for meetings.

British Telecom saved 97,000 tonnes of carbon dioxide – and A$560 million – in one year by replacing meetings with video conferencing. In Australia, Telstra claims nearly half of all air travel is for business purposes, and that firms could save time, money and 2.4 million tonnes of carbon dioxide equivalent a year through high-definition video conferencing.

Telecommuting – or teleworking – where people work away from their firm's office (often from home) can also be used in some cases to reduce air travel.

People who still need to fly can use online carbon calculators to determine how much carbon their flights produce and purchase carbon offsets for those emissions. Many airlines already have schemes that allow passengers to pay an amount to offset the emissions created by their travel.

Critics point out that offset schemes only deal with the carbon problem after it has been created, and are in danger of being regarded as 'feel good' measures. Carbon calculators vary broadly in their estimates of emissions and there is also no regulatory system to ensure that the offsetting schemes achieve what they promise.

Perhaps the simplest ways to reduce the carbon footprint of your trip is to re-think how you travel to your destination, where you fly to, and whether you fly at all.

A flight in the tropics has a different effect to a flight in the mid-latitudes. Nitrogen oxides emitted from aircraft increase ozone and reduce methane, two gases that have a warming effect. But in the tropics the brighter sunlight creates ozone five times faster than at other latitudes increasing the warming effects.

Short-haul flights typically make disproportionately large carbon emissions. One UK study showed that a flight of 500 kilometres (around the distance from Sydney to Canberra and back) uses more than 20 per cent of its fuel in taking off and landing.

There are often more environmentally friendly travel options. Replacing flying with other means of transport such as rail can more than halve your trip's carbon emissions. For example a flight from Sydney to the Gold Coast would produce around 0.3 tonnes of carbon dioxide compared to 0.1 tonne by rail.

Boxes
Box 1. What aviation emissions do
Box 2. Flying smarter

Related sites
What difference can we make? (Nova: Science in the news, Australian Academy of Science)
Climate action: Get energy efficient (Sustainable Development International/United Nations Environment Program)
Towards a high-bandwidth, low-carbon future (Climate Risk, Australia)

External sites are not endorsed by the Australian Academy of Science.
Posted February 2009.