+ Global population will be 9.5 billion by 2100

A recent report by the Institution of Mechanical Engineers makes suggestions for the role that the engineering profession can play in tackling the problems posed by population growth – estimated to be 9.5 billion by 2100. Whilst the proposals are not contentious, how are they to be achieved?

The report makes three recommendations:

1. Governments adopt five Engineering Development Goals in the key areas of energy, water, food, urbanisation and finance

2. Provide all nations and leaders with engineering expertise – specifically expand the remit of the UK's Department for International Development (DFID) to train multidiscipline engineers to provide other governments with low-cost engineering expertise

3. Help the developing world to 'leapfrog' the resource-hungry dirty phase of industrialisation – as the majority of growth will be in the southern hemisphere but knowledge of tried solutions are in the north.

The report's recommendations are based on the premise that technical solutions to meet the challenges of population do exist. But to deploy them we need an understanding of politics and behavioural change, not traditionally areas of capability for engineers.

Firstly, the report states that 75% of the population will be in urban settlements by 2100. While national governments, the focus of the report's recommendations, set policy and deliver fiscal packages that stimulate change, Arup's own experience is that the major interventions in reducing resource use or building resilient urban settlements happens at the city or regional administration level.

Understanding these different contexts leads to the challenge of the 'developed' versus the 'developing', 'north' versus 'south'. We should never assume that the knowledge flow will be one way. UNESCO statistics show a clear link between GDP per capita and the number of tertiary education places in engineering and construction, but Arup knows that our engineers need on the ground experience in the developing world – a cultural and contextual understanding – to effect meaningful change.

Understanding culture and human behaviour is my third, and possibly the most significant, point. The interventions recommended in the report – such as reducing water consumption and energy use, and cutting down food waste – require changes in behaviour. This talks to issues far beyond the traditional engineering realm that require great understanding of the differing motivations of a variety of urban populations.

What might it take to stop the residents of Addis Ababa throwing waste in to a river that is also their water supply? Better waste systems would be the first step, but how many city departments will need co-ordinating to achieve that? Who would need to be influenced, who would fund this? And why will residents change their habits?

Then take a resident of a developed city, say New York. What is required to stop those residents making short journeys by car, or leaving electrical appliances on standby? Congestion charges and energy tariffs are just part of the solution. How might we successfully shift the lifestyle choices of an affluent population?

This is not the traditional role of the engineer, but Arup has realised that to deliver interventions at this level – to 'shape a better world' – we need to exert political and social influence. As well as working with national government, this means working at a more local level sharing best practice, whether through cities networks such as the C40 or with NGOs in the developing world. Indeed a challenge for our future.