Thanks to ecoslogic@yahoo.com (who I think is Mark Moscio from Greenway International. A private firm working on agenda 21 issues) for posting his comment about how air travel is unsustainable. I agree and hope that there will be more discussion and posting of resources about this issue here on my blog. I've done a little internet search myself to learn some current info/advice. There is such a thing as "Emissions Calculators" that individuals can use to find out how much it would take to offset the resources used during their travel. Here's an example where you can estimate your costs related to your lifestyle (air travel, cars, etc).

http://www.ecoplan.org/general/responsibility.htm

Also, the Climate Care website http://www.climatecare.org/index.cfm helps you figure out how much you personally damage the atmosphere on your flight. For example, my upcoming flight to India turns out:

Your emissions from this flight are: 3.62 Tonnes of CO2
The cost to offset this CO2 will be £ 27.15

When you buy a carbon offset through ClimateCare, your money is used to fund projects that reduce emissions on your behalf. As well as making savings in greenhouse gases, the projects also have wider benefits to the local communities and environment too. They have three types of projects:

Renewable energy - replacing non-renewable fuel such as fossil fuels
Energy efficiency - reducing the amount of fuel needed
Forest restoration - absorbing carbon as the trees grow

For example, here is a project they fund in India (my destination):

India: Schools

Greener stoves cook tastier chapatis

Project partner: Nishant Bioenergy

Ashden Awards Winner, 2005.

Background

In the Punjab, as across India, schools cook their food on expensive LPG, a fossil fuel. Meanwhile, people who made biomass briquettes are struggling to make a living as there is little demand for their fuel. At the same time farmers are burning their crop wastes in the fields – which is wasting a valuable energy resource.

The Project

Enter Ramesh Nibhoria a local engineer and entrepreneur who solved three problems at once. He has developed the Sanja Chulha - literally, 'combined cookstove' – which is specially designed to run on briquettes made from crop waste left over from the harvest. These cut CO2 emissions (the crop waste is a renewable source of energy), cut schools’ fuel bills and give a new income to the farmers, who can now sell their waste to the briquette makers
Ramesh builds the stoves and sells them to the schools on a "hire purchase" basis. As the briquettes are half the price of LPG schools pay Ramesh back from the money they save and own the stoves within 18 months.

Climate Care’s Involvement

The problem that Ramesh faces is that he cannot fund a new stove until he has received the money back from the school – so his production was limited to 3 stoves a year. Although he has a large order book the banks have not lent him any money. Climate Care has provided a capital sum as a “revolving fund” which means he can gear up production to 50 units a year. Ramesh uses money from the fund to buy the materials he needs and to pay the wages; the fund is replenished as the schools pay back their loans – meaning the monies used again for more stoves.

Benefits

Not only does this project reduce CO2 emissions through replacing fossil fuel with biofuel, it also benefits farmers through extra income and schools through lower fuel costs. The stove has also proved popular with the pupils. As one school cook explained: "The chapatis taste just like the ones they have at home - so now they always want more!"

Monitoring

Climate Care has commissioned MITCON Consultacncy Services Ltd. to write a third party report and on this project and to monitor the emissions reductions it acheives.

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http://www.climatecare.org/projects/countries/index.cfm?content_id=33C26EB4-01E8-0F75-7F19BE1B330AD0BA