The findings "suggest that adaptation measures to reduce heat effects should be adopted widely if severe economic impacts from labour productivity loss are to be avoided if heat waves become as frequent as predicted," wrote the authors.

Negative impacts from heat can include accidents due to concentration lapses, and lower productivity due to impaired decision-making or fatigue.

Already one of the warmest continents, Australia is particularly at risk of more frequent heat waves as a result of global warming.

It is also one of the world's top per capita emitters of planet-warming greenhouse gases.

The world's nations are negotiating a global pact to limit carbon emissions from fossil fuel burning. The agreement is meant to be sealed at a global summit in Paris in December, and take effect from 2020.