Changing demographics may alter climate vulnerability - researchers

Factors such as changing migration rates and life expectancy – beyond simple estimates of population increases – could help scientists predict more precisely how climate change will impact people in the future, researchers said Wednesday.

For instance, data suggests that life expectancy in Europe could rise by almost 20 years by 2100, while Asia's sex ratio, now skewed toward more boys, could almost even out over the same period, the scientists wrote in the journal Nature Climate Change.

Such differences will be important for assessing the vulnerability of populations to climate change and could help avoid misleading conclusions, said Raya Muttarak, a demographer with the International Institute for Applied Systems Analysis, based in Austria.

Scientists "tend to not concede the fact that the socioeconomic and demographic components will change in the future", Muttarak said in an interview with the Thomson Reuters Foundation. But "as demographers, we can forecast this".

Right now, when assessing vulnerability to climate change, many scientists use data solely based on future population sizes, she and colleague Wolfgang Lutz said. But more specific data could help better anticipate how the world will look and act 100 years down the road, the analysts said.

Their organisation has made predictions on the age, gender, population, and educational makeup of about 195 countries through 2100, including both developed and undeveloped countries. The data is available online.

Muttarak said the inclusion of demographic shifts in climate research has been "neglected" simply because many scientists do not know the data is available.

"We're saying that we know what the population composition will look like … who they are going to be," she said. The data exists "and can be used."

INEQUALITY AND CLIMATE CHANGE

Paul Routledge, who studies geopolitics and climate change at the School of Geography at the University of Leeds, said social and demographic sciences have taken a "significant backseat" in climate change research until recently.

"Some recent interventions have begun to open up what the social sciences of climate change would mean," he told the Thomson Reuters Foundation. "Those issues about vulnerability are absolutely critical."

Research such as IIASA's could help expand conversations on issues such as what growing income inequality might mean to climate change vulnerability, he said.

Muttarak said the data suggested that many people around the world will be healthier and more educated by the turn of the next century.

"When the society has a relatively highly educated group or population, we have shown that they have better adaptive capacity," she said. "The younger generation is not the same as the older generation."

Routledge warned, however, that climate change and its effects are impossible to predict 100 percent accurately.

"Prediction is highly problematic," he said. "There is this deep uncertainty … that is unfortunately endemic to the issue of climate change."