Rising sea levels, a direct impact of the Earth’s warming climate, is intensifying coastal flooding. The findings of a new study show that the projected negative economy-wide effects of coastal flooding are already significant until 2050, but are then predicted to increase substantially towards the end of the century if no further climate action on mitigation and adaptation is taken.
Sea level rise is one of the most severe impacts of climate change, with rising waters amplifying coastal floods, threatening coastal communities, infrastructure, and agriculture.
New IIASA-led research for the first time assessed the economy-wide effects of sea level rise globally and in particular in G20 countries. The study is also innovative in terms of looking at G20 countries explicitly, that is, countries that are big emitters and at the same time affected by climate change. All individual G20 countries could potentially limit the residual economy-wide impacts to below 1.0% of GDP if appropriate adaptation measures are taken.
The study’s lead author and IIASA Risk and Resilience Deputy Program Director Thomas Schinko says that by 2100, if without further mitigation and adaptation and assuming continued sea level rise, projected annual global economy-wide losses can amount to more than 4%.
“With ambitious mitigation and adaptation, the model results show that this number can be reduced to below 0.5% of global GDP loss, despite the associated costs for adaptation measures and residual impacts. This confirms the importance and economic efficiency of adaptation in the long term: Making sure that coastal communities and their infrastructure are climate-resilient will affect economies across the globe much less than persistent climate impacts in the absence of climate action.”
The highest levels of annual GDP impacts in relative terms are projected for China. In 2050 and with no further adaptation, economic losses may amount to 0.8-1.0%. Other regions with severe economy-wide damages by 2100 under no adaptation are Europe and Japan.