Victoria must prepare for increasingly devastating bushfires as climate change takes hold, according to the Climate Council.

A new report on the state – already the most fire-prone in Australia – warns record-breaking heatwaves caused by global warming will lead to longer, more severe fire seasons.

The economic cost of bushfires in Victoria this year is estimated at $172 million, and this figure is projected to double by 2050.

By 2030 twice as many professional firefighters will be needed in the state than were employed in 2010, the Climate Council says.

Population growth around Melbourne, encroaching into surrounding bushland, will increase risk.

“Melbourne’s rural-urban fringe is among the most vulnerable in the world to the bushfire hazard,” the report says.

“Already fire-prone regions are becoming more fire-prone and risks to lives and property continue to increase in parts of Victoria.

“Hard decisions will have to be made about the ongoing liveability of those regions, as they become increasingly dangerous to live in.”

The Climate Council says this is a critical decade for action to restrict global warming to the internationally agreed two-degree target.

The ABC says a draft CSIRO discussion paper it has obtained finds the cost of damage caused by extreme weather in Australia could reach $1.4 trillion by 2100. The paper warns climate change and poor planning is leaving the nation increasingly exposed.