I wonder what the UK would say if Donald Trump was to extend his state visit from 3 days to 25?  That would be the consequence of adopting my proposed Travel Law.

Flying is quite rightly in the spotlight since emissions from aviation are significant, and expected to rise rather than to fall. We hope to be able to fly on renewable fuels in the future but supply of these fuels will inevitably be limited.

There are also many other demands for energy and no-one knows where all the renewable energy we’ll need is going to come from*. So as well as reducing flying per se, we also have to reduce total energy use from all forms of transport.

But people will continue to want to travel and travel has some benefits. We get insights into other cultures which can make us more tolerant and understanding of others. And sometimes it’s a good idea to get groups of decision-makers together in the same room.

To help balance the energy requirements of transport with the benefits of travel, I suggest a Travel Law. The energy required to transport us is related to the distance travelled, so we should travel less often and if we’re going to travel a long way, by whatever means, we should make it really worthwhile. According to my Travel Law, for every 250 km travelled you should stay at least one day at your destination. Long trips would be reduced since the total investment of time and money would be much greater, and frequent fliers would not be able to travel so often.

Here are some examples of how this would work:

If I’d followed the Travel Law when I went to Bonn (by train) to meet the UNFCCC in February I would have stayed 3 days instead of 24 hours. With this extra time I could have met other people and organisations, worked digitally and rested – all benefits to me and my work.

Once a year one of the ZeroMission team travels to visit carbon offset projects. If we followed the Travel Law we would stay longer, giving us greater understanding of the projects and their contexts.

If I followed the Travel Law whenever I go to the UK to see friends and family I would stay at least a week. I could travel less often but spend more time with people who are important to me when I did.

And according to my Travel Law President Trump and his entourage would stay in the UK for 25 days on the state visit. Given the demands of spending so much time being diplomatic, perhaps the President would have stayed at home.

*In particular biofuels are talked about as a solution for many sectors but without a co-ordinated strategy for land use.