Madam, - Mark Sugrue points out (August 25th) that an airliner uses almost the same amount of fuel per passenger mile as an average car. He goes on to suggest that parking one's car at the airport will "naturally offset" the emissions from the subsequent flight.
It sounds too good to be true and sadly, it is. Ignoring the fact that when on holidays one is likely to use a car or some form of local transport, the big problem with international air travel is simply the huge distances it allows us to cover in a short space of time - distances that we would otherwise never contemplate. A round trip to the south of Spain is 2,400 miles, almost a quarter of what most people drive in a single year.
To offset emissions as your reader suggests would require leaving the car at the airport for a period of three months.
Oisín Coghlan of Friends of the Earth ("We have to be weaned off flying", Opinion, August 23rd) is, unfortunately, correct. If we are to avoid the worst effects of climate change we must dramatically reduce our emissions and stabilise atmospheric carbon dioxide concentrations. During the middle of the last Ice Age this stood at 180 parts per million (ppm). Before the industrial era, around 1800, it had stood at 280ppm for several thousand years, but since 1900 it has risen rapidly from 290ppm to 380ppm and continues to rise at more than 2ppm per year.
If 100ppm is the difference between an Ice Age and today's climate, what can we expect from the extra 100ppm already in the atmosphere, whose effects we are only just beginning to experience?
Regardless of all future emissions, current levels will continue to affect us for decades to come. Even more alarming is the expected rise to between 450 and 550ppm by the middle of this century.
The UK Met Office has recently published online an animation of the globe illustrating the temperature rise since 1870 to the present day with a prediction of what is to come until 2100. I urge your readers to view it at www.metoffice.gov.uk/research/hadleycentre/ar4. It is, to say the least, frightening. - Yours, etc,
BRIAN DILLON, Callan, Co Kilkenny.
Madam, - Mark Sugrue assures us that car travel is even more destructive to the environment than air travel in terms of fuel consumed per passenger mile.
"Go green, get on a plane" seems to be the message. This will come as a relief to those who might previously have been considering the awkward but noble option of taking the car to New York for a shopping trip.
Is it that difficult to understand that both modes of transport are bad for the environment, and that we might therefore consider trying to reduce our reliance on both of them? - Yours, etc,
HUGH McCABE, Rialto Drive, Dublin 8.