US: Developing countries are facing a “double whammy” of growing population and an increase in climate change impacts, according to an article in Nature Climate Change. But local-level information about who the most vulnerable are and where they live is either lacking or lying unanalysed. Hence, some researchers are combining demographic data — which includes information on population size, birth and death rates, migration and age structures — with geographic and spatial data to identify where climate change might hit the hardest.
Deborah Balk, a population and climate researcher at the City University of New York, US, put together the GRUMP (Global Rural–Urban Mapping Project) dataset, by collecting population data from regional censuses and land elevation information from satellites, and by looking for regions that are most illuminated at night to identify urban areas.
Her results revealed that cities in low-lying coastal areas are growing the fastest. In Asia, “one in ten people, and one out of every eight urban dwellers, lives on the coast no more than ten metres above sea level, and that number is increasing,” said Gordon McGranahan, Balk’s colleague. “People are running towards risk, particularly in China, but also in other parts of the world such as Bangladesh, where more than 40 per cent of the land area is within ten metres of sea level.”
Meanwhile, many areas in Africa are facing water shortage, and climate change may stir conflicts and mass migration.
Mark Montgomery, an economics professor at the State University of New York, United States said that having reliable data on where people are at risk might help populations adapt and speed up disaster relief efforts. Social scientists may be able to tell relief agencies where to go, who lives there and what makes them vulnerable, he added.