Australia's volatile climate, which experts warned will produce increasing weather extremes, has already contributed to a loss in farmland the size of Ukraine, a leading analyst warned.

Much of the land lost will have been of poor quality, used only for grazing, but in some areas, notably parts of Western Australia, extended dryness is threatening what have historically been arable farms too.

Australia's Climate Commission warned earlier this week of a high risk that the heatwaves, drought, wild fires and cyclones which have reached at least part of the country over the past few months will become more severe.

Yet already Australia's farmland is on the decline, with more than 60m hectares (600,000 square kilometres) - an area the size of Germany and the UK combined,, and equivalent to a 13% loss - falling out of production over the past two decades.