The latest evaluation of coastal flooding risk up to the end of the century combines climate science with likely economic impacts and possible outcomes for populations living near coastlines. It uses modelling in an attempt to predict how sea level rise combined with episodic extreme weather in the form of storm surges might occur in a world where temperatures continue to rise due to human-caused carbon emissions. The inexact science of prediction is becoming more accurate – even if still imperfect – and countries need to sit up and address the consequences, Ireland included.
The combination of sea-level rise, storm surges and high tides could expose an extra 23 million people to coastal flooding by 2050, even with relatively ambitious cuts to emissions, the study published in the journal Scientific Reports concludes. In a worst-case scenario where emissions continue to rise and no efforts are made to adapt to rising sea levels, coastal assets worth €12 trillion could be at risk by 2100. Rising sea levels caused by global heating could mean one-in-100-year floods would become one-in-10-year floods by century end.
The analysis identifies "hotspot" regions at risk of extensive flooding, of which northwestern Europe, including Ireland, is among the most vulnerable areas. This analysis shows the urgency of action needed to address sea-level rise via climate mitigation and adaptation, such as better coastal defences, as much of the rise is unavoidable.
Such studies have in the past been dismissed as scare-mongering, and criticised by climate science deniers for failing to take into account adaptation in the form of current flood defences, future measures and human resourcefulness.
This is critical research "because it provides politicians with a credible estimate of the risks and costs we are facing, and a basis for taking action", according to co-author Prof Ian Young of the University of Melbourne. This data should act as a wake-up call to inform policy at global and local government levels so more flood defences can be built to safeguard coastal life and infrastructure.