The dangers of climate change are more visible than ever

At least a tenth of the world’s population, almost a billion people, will need to migrate as world temperatures reach 2°C of warming.

The impact of climate change is now more visible than ever before.
The impact of climate change is now more visible than ever before.

Global warming has been a persistent warning over the past seven years and the message is particularly relevant as we see desperate migrants flee from countries where drought has triggered and interacted with political unrest and civil wars.

What should be even more unsettling is that there is now only a perceived 50:50 chance that we will limit global warming to a 3°C rise. At such temperatures a third of the world population, or three billion people, will be at risk.

Additionally, once temperatures reach such levels, opinions indicate that there is only a 10% to 20% chance that they can be stabilised, yet at 5°C of warming only half of the world population would survive. There is, therefore, around a one in three chance that over four billion people will die from global warming.

Opinions firmly indicate that the weather is already more extreme due to climate change; a conviction that has grown over the past year or so. Notwithstanding the official forecasts, it is considered more likely than not that sea levels will rise by more than 0.8m this century. Whilst most now follow official assurances that the Arctic sea ice will not disappear until mid-century, it is considered more than likely that we will have a series of tipping points by then, which will take temperatures beyond our control.

These opinions were discussed at a recent symposium of civil engineers and their guests in Newcastle. The results of this discussion, together with those from previous events in the North East in 2013 and 2008, provide an interesting and consistent set of data that will surprise and horrify many. The findings also tie in with a much larger non-technical based census in 2012, featuring opinions from 700 people, many of them school children, in advance of a climate change event at York Minster.

In the course of their professional practice, civil engineers and structural engineers are accustomed to weighing up and mitigating against ill-defined risks and hazards, even where the perceived risks are assessed with probabilities as low as one in 10,000. As the dreadful hazards associated with climate change are clearly orders of magnitude more likely to occur than most of the dangers we deal with on a daily basis, it is clear that as engineers we have a duty to take action.

Almost the whole basis of engineering needs to be reconsidered, to take account of the new threats and conditions that are facing us. The results from the latest symposium indicated a consensus that engineers should be taking a lead on the issues associated with climate change.

If we act now we can start to ready our infrastructure for the new conditions by preparing for floods, drought and heatwaves. We can do much to cut carbon through choices in materials and changes in transport systems. My first project in 1980 was the Thames Barrier, which saved London 30 times over the winter of 2013/14. Over the past decade or so we have done very little and are still plagued by doubts over the risks. I would hope that these opinions will trigger action.

The concerns expressed by the surveys are not yet shared by the UK electorate as a whole. The results also differ from advice given by international committees of scientists through bodies such as the IPCC. However, through conversations with several leading scientists, I have come to believe that the committees tend to reach a consensus by under-estimating the dangers. Where the findings can be checked, there are grounds to believe that the opinions of engineers have proved more accurate than expert advice.

For example, one of the questions discussed at the climate change event in 2008 asked about the expected extent of the summer ice in 2013 compared with its extent in 2000. Although official IPCC graphs from 2007 gave a value of 93%, the 2008 symposium opinion was a much more pessimistic 58%. Five years on, we can see that as a result of dramatic changes in the sea ice over the past few years, that value of 58% coincides exactly with the current trend line for 2013.

Climate change is a clear and present danger and, while I am heartened by an increase in those who are sitting up and taking note, we all need to be taking our role in tackling the issue more seriously.

About the author

Robert Thorniley-Walker is a chartered environmental engineer and is Chairman of the Institution of Civil Engineers (ICE) North East.