“Mapping the Impacts of Climate Change: Areas of Greatest Concern at 4°C Global Warming”
A new set of maps has been released, showcasing the areas of greatest concern for experiencing severe climate-related impacts at 4°C global warming relative to pre-industrial levels. These maps highlight regions where people may be exposed to severe climate-related impacts, as well as areas where multiple severe impacts may occur simultaneously. The impacts shown include extreme heat stress, river flooding, fire weather, drought, and food insecurity.
The first map focuses on regions where multiple severe impacts may coincide at 4°C global warming. This includes extreme heat stress risk, river flooding, drought, wildfire risk, and present-day food insecurity. The map identifies locations of particular concern where these multiple severe impacts overlap.
The second map highlights extreme heat stress risk, which is determined by wet bulb globe temperature (WBGT) above 32°C. Areas where WBGT exceeds this threshold for more than 10 days per year at 4°C global warming are shown. This poses a significant health risk to vulnerable populations and those with outdoor jobs.
The third map addresses river flooding, which can be exacerbated by heavy rainfall and human activities. Major river basins with over 1 million people per year projected to be affected by river flooding at 4°C global warming are identified. This projection is based on present-day population and flood management measures.
The fourth map focuses on drought, specifically severe and extreme drought defined by the Standardised Runoff Index (SRI). Areas with a more than 25% increase in time under severe and extreme drought at 4°C global warming are highlighted. Regional variations in response to climate change are evident, with the Mediterranean region experiencing a notable increase in drought.
The fifth map examines fire weather risk, which increases under hot, dry, and windy conditions. The McArthur Forest Fire Danger Index (FFDI) is used to quantify this risk, with areas projected to have a “very high” risk for more than 10 days per year at 4°C global warming identified. This metric indicates fire weather rather than actual fire activity.
Lastly, the sixth map focuses on food insecurity, highlighting countries where more than 30% of the present-day population is exposed to moderate or severe food insecurity. This measure is based on the Food Insecurity Experience Scale and reflects present-day vulnerability factors. However, it is important to note that food production is closely linked to climate hazards such as drought, heat stress, flooding, and fire.
These maps provide valuable insights into the potential impacts of severe climate change at 4°C global warming, emphasizing the urgent need for mitigation and adaptation strategies to address these challenges. For more information and detailed data on observed climate impact trends, please refer to the provided links.