November 27th 2014, by Damian Carrington, The Guardian.
Ageing population will compound deadly effects of heatwaves caused by climate change.
The researchers from the UK’s science academy warn the world is not prepared for the extreme weather which is already being exacerbated by climate change today.
The world’s population is expected to swell from 7bn today to a peak of 10bn by mid-century, and the new analysis examines for the first time how this boom will affect the number of people hit by extreme weather, if the relentless rise in carbon emissions is not reversed.
The combination of population growth and climate change means the impacts of flooding around the world will be increased fourfold and drought impact will be trebled. The report also warns that failure to prepare for more extreme weather would cause huge economic damage, meaning entire nations having their credit ratings downgraded and major companies going bust.
Heatwaves are the climate impact most exacerbated by population changes, because they are particularly dangerous for people over 65 and the global population is ageing quickly.
The greying populations of UK and western Europe mean the region is particularly affected by this multiplication affect. In 2003, a 20-day heatwave killed 52,000 people across Europe. Without action on climate change, once-rare heatwaves will happen every other year by 2100.
The US, China and north Africa will also be among those suffering from the magnified impact of heatwaves. The combined climate-population damage from flooding and droughts will be felt heavily in western Europe, while India and sub-Saharan Africa will be struck by all three types of extreme weather.
“Extreme weather has a huge impact on society and globally we are not resilient even now,” said Professor Georgina Mace, from University College London and who led the group of 24 physical, social and economic scientists. “This is why we have seen these horrible events [like typhoon Haiyan and hurricane Sandy] in the past few years, with many people affected. If we continue on our current trajectory the problem is likely to get much worse as our climate and population change.”