Choices, Cost and Carbon offset

Another day of sorting out visas and tickets, hopefully by the end of tomorrow I will have everything sorted to get me to Beijing at least! Thanks so much for all the comments, I will try to address some of the issues here, sorry I can’t respond to every question. This is all such a surprise to me, I didn’t think anyone would be so interested in what I am doing, but I am glad I have sparked a debate. I think it is important to think about this in terms of both the impact of air flight on our environment and a much wider debate about the future for our environment.
Choices
I was reflecting today on how easy it is in Machynlleth to make the right choices, it is easy to recycle and compost my waste and I can easily save water and energy too. There are shops and a market where I can buy local food and I can cycle everywhere, even though it is often steep up a mountain (I have lost weight and am fitter too). I wonder how easy it will be when I am away? People have questioned how ‘green’ I will be along the way and mentioned taxis and food as two examples. I don’t take taxis now and do not intend to start. Most bus and train stations are more likely to be in the centre of a city than an airport. Unless there is a desperate need for a taxi (or it is horse drawn) like I am about to miss the boat to Australia, then it is walking for me. In terms of food, I need to eat on the way and would eat if I was at home anyway. Like now, I will always search out local and fresh (organic?) food, which may be easier in certain areas of Southeast Asia anyway, any ideas anyone? I read about a load of cafes in Vietnam where they train street kids in catering and get them work in cafes so I will try to find one of them too. It is all about choices, and I will try to make the best one.
Cost
In terms of cost, my trip is more expensive but it is not out of reach for anyone, you just need to save longer. All the visas are expensive to sort out but otherwise it is ok. The bus to Moscow is £132, The Trans-Siberian £190. I have seen various prices for the train from Beijing to Hanoi between £80 and £160. Trains, buses and boats in the rest of Southeast Asia seem very cheap. The boat to Australia is £1000, this is the most expensive bit and although it will be a great experience to be on the cargo ship I will prefer to sail out of Oz as it will be cheaper and greener.
Carbon Offsets
What about carbon offsets? This is a difficult one to answer and my feelings are mixed. We really need to reduce carbon emissions in the first place, and all those trees just hold onto the carbon ‘til it is released anyway when the tree dies. I think offsetting by direct energy saving activities is better such as buying low energy light-bulbs (they save you money!) or improving insulation in your home.