Helping developing nations to adapt to climate change such as floods or heat waves can give bigger economic benefits than a focus on deep cuts in greenhouse gas emissions, a study indicated yesterday.

A total of US$10 trillion spent on adaptation, ranging from research into drought-resistant crops to measures to limit a spread of diseases such as malaria, would provide US$16 trillion of economic benefits over the coming century, the study suggested.

"We talk immensely about cutting carbon emissions, but there are many other ways to deal with climate change," said Bjorn Lomborg, Danish author of "The Skeptical Environmentalist" who commissioned the study by Italian researchers.

"Everyone pays lip service to adaptation but in reality we rarely talk as much about it as cutting carbon emissions," he said of the study, meant to provoke debate about a new UN climate treaty to be agreed in Copenhagen in December.

"The authors find that ... adaptation achieves more than mitigation in terms of reducing the damage from climate change," he said. Mitigation means curbing emissions of greenhouse gases and often gets most attention at UN climate negotiations.

The study said that the highest economic benefits would come if adaptation went hand in hand with moderate curbs on emissions. In the best case, US$9 trillion spent would give US$19 trillion of benefits.

"The optimal strategy to deal with climate change entails the adoption of both adaptation and mitigation measures," Carlo Carraro of the University of Venice and co-authors from the Fondazione Eni Enrico Mattei in Italy wrote.