KUALA LUMPUR: The potential for a global tree-planting drive to curb climate-change risks has been overestimated, scientists warned, flagging issues with maps and data used in a recent study and urging greater efforts to cut heat-trapping emissions by other means.

In July, researchers at the Crowther Lab, based at Swiss university ETH Zurich, published a study suggesting the best way to keep climate change in check would be to replant trees on destroyed forest areas the size of the US.

But in a response letter published in the same journal Science, scientists at the University of Bonn and Nairobi-based research centre World Agroforestry said there were limits on the number of trees that could be grown on lands included in the initial study.

Eike Luedeling, a professor at the University of Bonn’s Institute of Crop Sciences and Resource Conservation, said that reforestation should not be seen as a substitute for curbing emissions from using fossil fuels. “Yes, we can all plant trees ... and if we still keep emitting carbon dioxide like crazy, we will not have solved anything — we just bought a little bit of time,” he said. “If we want to control climate change, there is really only one answer ... we have to cut emissions,” he added by phone.

Crowther Lab scientists this year published what they said was the first study of how many trees the world could support, where they could be grown, and how much carbon they could store. The study analysed the maximum amount of carbon that could be captured if all available degraded forest areas not used by humans were replanted and allowed to mature.

Published in Dawn, October 23rd, 2019