Companies are failing to disclose sufficient detail about how exposed they are to the potential risks of climate change, a global task force said in a report on Wednesday.

Many investors have called on companies to provide better communication on how climate change could impact their businesses, amid concerns that assets are being mispriced because the full scale of the risk is not being factored in.

"Given the speed at which changes are needed to limit the rise in the global average temperature – across a wide range of sectors – more companies need to consider the potential impact of climate change and disclose material findings," the report said.

The Task Force on Climate-related Financial Disclosures (TCFD), set up by the G20's Financial Stability Board, found in its report that climate related disclosure had improved since 2016 but only about a quarter of companies disclosed information aligned with more than five of the TCFD's 11 recommendations.

The TCFD launched a voluntary framework in 2017 that calls on companies to provide climate-related financial disclosures in their public annual financial filings.

Other recommendations include disclosing metrics companies use to set internal climate targets and describing processes for managing climate-related risks.

The task force published its second status report on Wednesday, showing 785 companies and organisations, with a combined market capitalisation of more than $9.2-trillion, had committed to supporting the TCFD framework, a more than 50% increase from the first status report published in September.

Companies supporting the framework include insurance groups AXA and Aviva, oil majors Royal Dutch Shell and Total and mining companies Anglo American and BHP.

Climate scientists said last year that keeping the Earth's temperature rise to 1.5 °C, a level that would stave off the worst effects of climate change, required rapid changes in the way people used energy, eat, lived and travelled.

But Wednesday's report said there was only a 3% increase from 2016 to 2018 in the number of firms disclosing information on the resilience of their strategies, taking into consideration different climate-related scenarios, including a 2 °C scenario or lower.

The Paris climate agreement, adopted by almost 200 nations in 2015, set a long-term goal to limit global warming to "well below" a rise of 2 °C above pre-industrial times while "pursuing efforts" for the tougher goal of 1.5 °C.

More than 200 of the world's largest listed companies have forecast that climate change could cost them a combined total of almost $1-trillion, a report by charity group Carbon Disclosure Project showed this week.