As flood risk rises, populations abandon areas
Source: Middle East Insurance Review | Feb 2024
New research has revealed the emergence of ‘climate abandonment areas’, which are locations that have lost population over the last two decades, from 2000 to 2020 due to climate change related flood risk.
The new research study, ‘Integrating climate change induced flood risk into future population projections’, conducted by First Street Foundation and published in the journal Nature-Communications in December 2023, integrates observations historic trends of population change, along with flood risk information, to uncover climate migration trends that are occurring in many high flood risk areas across the US.
The researchers used the US Census Bureau’s latest full population count data for 2020 and applied its most granular level, the census block, with the First Street Foundation’s property specific flood risk data. Through this process, ‘tipping points’ were found where thresholds of high flood risk directly impacted population change by varying degrees. There are 113m people that live in areas where flood risk has already been impacting housing choice and in the most extreme cases climate abandonment areas are observable.
These climate abandonment areas make up over 818,000 census blocks at present and saw a cumulative net loss of over 3.2m in population between the years of 2000 and 2020 directly attributed to flooding.
Over the next 30 years, the current climate abandonment areas are expected to see a decline of an additional 16%, some 2.5m people, due to flood risk. While those declines continue, high flood risk areas that see net population growth today, are forecasted to become climate abandonment areas and see net population loss in the future. These emerging areas are made up of blocks expected to hit the risk “tipping point” in the near future and subsequently see a 24% decrease in population by 2053, a cumulative loss of 5m residents.
First Street Foundation said the population exposure over the next 30 years is a serious concern. For decades we have chosen to build and develop in areas that we believed did not have significant risk, but due to the impacts of climate change, those areas are very rapidly beginning to look like areas we’ve avoided in the past. M