Top emitters of carbon are not disclosing the full risks associated with climate change, reducing the chances of meeting global emissions targets, a study by Carbon Tracker and the Climate Accounting Project (CAP) said on Thursday.

The CAP is an informal team of accounting and finance experts drawn from the investor community and commissioned by the Principles for Responsible Investment (PRI), while Carbon Tracker is funded by around 30 charitable foundations.

Of 107 listed companies assessed in the study, across sectors including oil and gas, automobiles and aviation, more than 70% did not reflect the full risks resulting from climate change in their 2020 accounts, the report released on Thursday by Carbon Tracker said.

"Based on the significant exposure these companies have to transition risk, and with many announcing emissions targets, we expected substantially more consideration of climate matters in the financials than we found," Barbara Davidson, senior analyst at Carbon Tracker and lead author of the report, said.

"Without this information there is little way of knowing the extent of capital at risk, or if funds are being allocated to unsustainable businesses, which further reduces our chances to decarbonise in the short time remaining to achieve Paris goals," Davidson added.

Eight out of 10 audits also showed no evidence of assessing climate risk, for example testing the assumptions and estimates made about impairments on long-lived assets, before the accounts were signed off, the report added.

A lack of consistency between climate pledges made and their treatment in financial accounts was also a concern, the study said, adding that none used assumptions in line with the Paris Agreement, which aims to limit global warming to no more than 1.5 degrees Celsius.

The report follows high-profile investor campaigns for better disclosure and analysis of the risk at energy companies and other heavy emitters such as miners.

Global accounting and auditing standard setters have since said that climate risks should be not be ignored in accounts.

The report was released ahead of the next round of global climate talks in Glasgow in November, where countries are expected to accelerate efforts to limit global warming.