New research identifying climate vulnerability hotspots has found that the number of people affected by multiple climate change risks, such as water supply risk, could double if the global temperature rises by 2 degrees Celsius, compared to the Paris Agreement targeted rise of 1.5 degrees Celsius.
The research was led by International Institute for Applied Science Analysis’ (IIASA) Energy Program researcher Edward Byers. Byers et al. investigated the overlap between multiple climate change risks and socioeconomic development to identify the vulnerability hotspots if the global mean temperature should rise by 1.5, 2, and 3 degrees Celsius by 2050, compared to the pre-industrial baseline.
The researchers from IIASA, Global Environment Facility (GEF), the United Nations Industrial Development Organization (UNIDO), the University of Oxford, and the University of Washington, developed 14 impact indicators in three main sectors—water, energy, and food & environment. The indicators include a water stress index, water supply seasonality, clean cooking access, heat stress events, habitat degradation, and crop yield changes.
“Few studies have consistently investigated so many overlapping climate and development challenges,” said Byers. “The research considers both different global mean temperature rises, such as the differences between 1.5 degrees Celsius and 2.0 degrees Celsius, and uses new socioeconomic datasets of income levels and inequality, to identify where and to what extent the most vulnerable in society are exposed to these climate-development challenges.”
At lower temperatures, hotspots occur primarily in south and east Asia, but with higher global temperatures, hotspots further spread to Central America, west and east Africa, the Middle East and the Mediterranean. At 1.5 degrees Celsius of warming, 16 per cent of the population of the world in 2050, 1.5 billion people, will have moderate-to-high levels of multisector risk. At 2 degrees Celsius of warming, this almost doubles to 29 per cent of the global population, 2.7 billion people. At 3 degrees Celsius of warming, that figure almost doubles again, to 50 per cent of the population, or 4.6 billion people.
Depending on the scenario, 91–98 per cent of the exposed and vulnerable population live in Asia and Africa. Around half of these live in south Asia alone, but Africa is likely to face greater risks as the least developed region with high social inequality.
“The poorest and most vulnerable countries are most at risk and this work will aid to identify integrated, cross-sectoral approaches and target resources for maximum impact,” said Astrid Hillers, senior environmental specialist at GEF.
Targeting socioeconomic development in hotspot areas is particularly important for reducing vulnerability in places where impacts will be most severe. Sustainable development in hotspot areas could reduce the number of people who are exposed and vulnerable by an order of magnitude, from 1.5 billion to 100 million, compared to the high inequality scenario.
“The research indicates locations where meeting the Sustainable Development Goals (SDGs) is not only important but also very challenging and shows the substantial importance of targeted poverty reduction that is required in some regions to reduce vulnerability,” said Keywan Riahi, IIASA Energy program director.
The research is part of a large ongoing partnership project, Integrated Solutions for Water Energy and Land (ISWEL), between IIASA, GEF, and UNIDO, who co-developed the research and are co-funders of the project.
As our May feature, Positioning for Peace, illustrates, Canada has a lot to offer the world in the journey to achieving global water security. Join the Canadian Water Summit on June 20th in Vancouver for a deeper discussion of Canada’s role in achieving global SDGs, particularly Goal 6 on water and sanitation.