In 2009 Professor Will Steffen reminded his audience at the Sustainable Cities forum that humanity’s global footprint had increased from about half a planet earth in 1960 to more than 1.2 planet earths in 2000, that only the poorest countries were living within the means of planet earth, that the US required five and Australia is not far behind. These numbers have increased since then. The bottom line is the imperative to reduce our demands on planet earth – of everything, probably by a factor of 4 or more, noting this imperative does not include the need to reduce greenhouse emissions – that is an additional concern.
But the factor that must be applied to the transport sector is far greater.
As Patrick Moriarty and his frequent co-author Damon Honnery explain, we have entered a period of “hyper mobility”. The number of passenger kilometres per year has exploded by a factor of 240 between 1900 and 2018. This is an extraordinary increase considering the less than five-fold global population growth during the same period, and is about thirty times the growth in real GDP. The average for motorised travel is now about 6,300 km per person. It is around 30,000 km per person in the US. Australia is not far behind but in some countries it is only a few hundred.
Moriarty calculates that if each person in the world were to travel 30,000 km per year in motorised transport “world transport energy levels along would be about 668 EJ, greater than total global commercial energy use (578 EJ) for 2018”. This situation is clearly unsustainable. The question is how to apply the brakes. This is the subject of an article by Moriarty and Honnery titled “ Reducing Personal Mobility for Climate Change Mitigation” which has been summarised below by Bart Hawkins Kreps, originally published by An Outside Chance, August 23, 2020. Refer
https://www.resilience.org/stories/2022-08-23/hypermobility-hits-the-wall/