The starting flag for this politically risky initiative will be waved with a memo to Cabinet this week, probably tomorrow, from Green Party leader and Environment Minister Eamon Ryan. This document will set out what is required from a demand-management strategy which will put us on course to dramatically reduce our reliance on cars by 2030.

In the effort to achieve radical change, there will be a smorgasbord of actions which could include congestion charging, increasing parking costs, reducing road space for vehicles through enforced low-traffic neighbourhoods and even — difficult though it is to contemplate in current economic conditions — an escalator on fuel prices to discourage or penalise usage.

The National Transport Authority has indicated the direction of travel by publishing models, including a 400% rise in parking charges on 2016 levels; a €10 daily charge for driving in cities such as Cork, Dublin, Waterford, Galway, and Limerick; a halving of public transport fares; and a 20km/h reduction on national road speed limits. It also postulates a substantial fall in car ownership in cities and major towns of between 10% to 14%.

While we are at the start of consultations with citizens and stakeholders, and the generations which will have to cope with global heating, it would be wise to concentrate on the benefits of hugely improved public transport at a dramatically reduced cost and the practicalities and timetables of implementation if we are to stand any chance of incentivising people to give up their vehicles.

Currently, the carrot looks insufficiently big or attractive to command the scale of transition that is needed. Even in London, where commuters are hugely more likely to travel to work by bus or train than their counterparts surveyed in Washington, Toronto, Paris, Düsseldorf, Turin, Dubai, and Bangkok, high ticket prices are seen as a massive disincentive to greater uptake.

Public transport of the future has to be convenient, comfortable, reliable, safe, and unbeatable value. It is a mighty challenge, but one which delivers huge prizes.

Unless everyone believes in this project, Mr Ryan will be cast in the role of Cassandra, the Trojan princess whose fate it was to accurately prophesy the future, only to see those predictions disbelieved or disregarded.