Alex has no qualms about taking long-haul flights occasionally for a holiday. Last year for example, she flew to Sri Lanka, where she met up with friends, toured the island and stayed for four weeks.

The company she works for has permitted such long breaks for a few years now, precisely to make it worthwhile travelling so far. She remembers how awkward it used to be trying to fit an exotic holiday into a week and not spend the whole time exhausted with jet-lag.

There's no doubt that the Sri Lankan economy benefits from these sorts of longer stays. And - though she's blown her carbon budget in one - the carbon impacts aren't as great as they used to be for long haul flights: the latest aeroplanes, though by no means perfect, are more fuel efficient and emit less carbon dioxide than older models. Alex flies a lot less than she used to, but when she does she flies further.

This year she plans to use her long holiday to visit the Ukraine. She's signed up with a travel package - a more organised version of inter-railing - that plots out her journey across Europe, booking her into small and eccentric hotels (the type she likes) en route and ensuring that the travel aspect is hassle-free - no eight hour waits in the early hours on some anonymous station platform.

Most of the journey is by train - those wonderful high speed Orient Express trains - or by coach. It could take around 24 hours of solid travelling but she has chosen the slower option, stopping over in Vienna and Brasov.

The journey is a package deal but she wanted to do her own thing in the Ukraine. So she's organised her own accommodation - staying with a Tatar family in a remote village, among other things. Then when she returns to the UK, she's taking another travel package, going via Poland.