When it comes to deciding what is the most environmentally friendly mode things are never simple. A person walking from Inveness to Edinburgh would consume and emit vastly more carbon than taking the train. The food they would need alone would have a carbon footprint well in excess of the mechanised transport option. However walking across Inverness or Edinburgh will usually be a greener way to travel.
In order to develop a greener transport system the knowledge based needs to improve substantially from the simplistic designation of green modes and less green modes. All modes are sometimes the greenest so good decisions depent on a decision making toolkit to inform the decisions.
The average emissions by distance and speed used in national transport appraisal documents, such as Transport Scotland’s STAG requirements, are a good starting point but they can only give a broad indication that needs more locally and scheme specific refindements for robust conclusions.
STSG wants to see more debate about these issues so please post your articles, thoughts and comments here.