I'm Arup’s global flood resilience...
With the confirmation during autumn 2015 that global temperatures are set to rise more than one degree above pre-industrial levels this year, the prospect of irreversible and significant climate change is becoming ever more real.
To cope with the rising sea levels, I believe that potentially millions of people around the world will need to adapt and support the interventions that will be necessary.
Rising sea levels is just one consequence of climate change, but I think it’s one of the most serious. Working in flood risk reduction, I’ve seen first-hand how remote communities, towns and cities are affected when sea levels rise temporarily at times of storm. Climate change would cause a permanent rise in sea levels and be accompanied by more violent storms. The combined effects could be devastating, disrupting the established way of life for entire regions and even whole countries.
In the period since the end of the last ice age, the Holocene period, climatic conditions and sea levels have been relatively stable, and humans have settled in coastal and riverside locations. These areas have offered clean drinking water; readily available fish and seafood; milder maritime climates; flatter, fertile terrain; and easy access to transport and trade networks. Today, 40% of us live close to the coast, and 10% of us – up to 300 million people – live in low-lying coastal areas. Are we now at one minute before midnight within this Holocene Period and at the beginning of a new Anthropocene Period of radically different weather conditions unknown in human history?
What might climate change mean for people living by the coast? There is a credible evidence base that sea levels could rise by as much as 5m sometime between 100 and 200 years from now. We can expect more and more frequent and extreme storms, heavier and more prolonged rainfall. At the same time, there will also be more droughts, and higher temperatures both during the day and at night.
This raises some big questions. Will our existing centres of population be able to adapt?Adaptation and building more resilience into existing communities will involve techniques like flood warnings, temporary evacuations, and improved emergency planning; designing buildings and infrastructure capable of withstanding flooding, but which can be restored to more normal use with relative ease; buildings that float in the event of a flood; and traditional physical flood barriers and walls.
For which communities is adaptation not a viable reality? In these places is there a willingness to move to a safer place on higher ground and effectively abandon coastal communities. Is there wider acceptance that this wholesale migration and building new cities in the years ahead will have to happen?
There’s no single solution to these issues. It’s clear that the case for water-sensitive and resilient design for the built environment is stronger than ever. But we’ll also have to adapt.
However we decide to deal with this, I don’t think anyone will be able to ignore it. Whether you live by the sea or not, you’ll need to accept and help pay for change. If these forecasts of the future begin to turn to reality then we are going to need exceptional leadership, vision and determination. We will also need an ability to collaborate across nations like never before.
The current European refugee crisis could just be a foretaste of what could happen if hundreds of thousands of people are displaced from their homelands as a result of rising sea levels. Let us be optimistic that mankind’s ingenuity, sense of humanity and instincts for survival will come to the fore. We need to ensure that we’re ready before this becomes an absolute necessity.