SDG 13: Take urgent action to combat climate change and its impacts

Ian Allison
Global Head of Climate Resilience, Mott MacDonald

The UN Climate Change Conference (COP21) negotiations held in Paris in December 2015 culminated in a global commitment to drastically cut carbon emissions with the aim of limiting global temperature rises to 2°C above pre-industrial levels.

The significance of this in achieving the 13th Sustainable Development Goal (SDG 13), to take urgent action to combat climate change, cannot be overstated. The average global temperature rise is already approaching 1°C, triggering weather extremes that cause huge damage to infrastructure and put populations at risk. Even if we could cease carbon emissions today, further temperature rises are ‘locked in’ due to historic emissions and the delayed response in some of the Earth’s natural systems.

Global economic losses to our infrastructure base attributed to climate impacts currently peak at more than $100 billion a year, with a clearly rising trend. We have also entered a period of unprecedented investment in infrastructure to meet the demands of a growing world population, urbanisation and the need for social development, especially in the developing world. Extrapolating these two trends shows that climate-related losses will breach $1 trillion a year in the 2030s unless significant investment in climate adaptation is mobilised.

Protecting our infrastructure

Protecting our assets from the effects of climate change will be one of the great demands made of engineers over the coming years.

Examining climate disasters reveals more about how insufficiently resilient infrastructure responds to severe climate impacts, and the effect on local populations.

In December 2015, as diplomats met in Paris to pledge the limit on global temperatures, people in the Indian city of Chennai struggled with the effects of extreme flooding after the most severe rainfall for 100 years caused widespread destruction and loss of life.

At the same time, Storm Desmond caused intense rainfall across the north west of England, resulting in Carlisle’s flood defences – designed against a 250-year return period event – being overtopped, again causing major disruption and significant economic losses.

There is no comparison in the scale of the tragedy. Chennai is a dense urban area of some five million people and suffered more than 500 fatalities. Carlisle – with a population of 100,000 – saw one fatality attributed to the floods (the storm killed three people in the UK). But Carlisle also experienced greater proportional economic loss, with disruption, reconstruction and insurance claims already estimated to run in excess of £1.5 billion.

The difference in impacts in these two urban centres perfectly illustrates the difference in climate resilience in the developed world – where effects are felt mostly by infrastructure with large economic losses – and the developing world, where human losses are far greater.

These examples highlight the importance of climate resilience measures that are appropriate to local conditions. But climate resilience is more than simply funding a new sea defence or flood wall. Carlisle sits in a catchment with a particularly rapid hydrological response. The £32 million recently invested in Carlisle’s flood defences are credited with delaying flooding and minimising the human tragedy, but did not prevent the flooding event from happening. ‘Failing safe’ must be a real consideration in all resilience planning. With climate impacts such as flooding set to become more frequent and extreme, there is an urgent need for broader measures to protect communities.

Taking action

We estimate that within 20 to 30 years we need to be spending some $200 billion globally each year to provide adequate resilience. The good news is that the financial sector is beginning to respond to the threat of climate change. Investors increasingly look for sustainable and resilient investments. Insurers already take climate resilience into account, and poorly adapted assets will soon become uninsurable. New investment bodies, such as the UN’s $100 billion a year Green Climate Fund, will raise the profile of climate resilient design.

The coming years will see accelerated government investment in climate resilience to protect communities and key assets. This will be complemented by an increase in developer-led and funder-led projects that make resilience a key requirement in order to secure financing.

Those entering engineering now need to consider climate resilience in a way their predecessors never had to, as design standards become less prescriptive and more outcome-based. Rather than specify the type, scale and dimensions of resilient measures, clients will demand that climate impacts are fully mitigated in a set area for a set time period. This changes how we think about engineering solutions, and how we deliver them.

At the start of the year, a survey of 750 experts by the World Economic Forum singled out climate change as posing the biggest threat to the global economy; an analysis that is unlikely to change for the foreseeable future and one that provides a real challenge to the engineering community.

Engineers entering the profession now will play a crucial role in ensuring new and existing assets are able to withstand this serious and growing threat.