Leading companies are offering only minimal information to shareholders on how global warming might affect their bottom line, research shows

The world's major corporations are failing to provide a full account to investors of the risks and potential costs of climate change, a new report said today.

The report, from the Ceres network of green organisations and investors, and the Environment Defence Fund, found companies offered only minimal information to their shareholders last year on how global warming might affect their bottom line.

It arrives at a time when there is growing support among US corporations for a push by Congress to pass the first US law to reduce greenhouse gas emissions.

Fifty-nine of the 100 leading global firms surveyed made no mention of greenhouse gas emissions at all, while 28 did not discuss potential risks from rising sea levels or other aspects of climate change, and 52 provided no information on what steps they were taking to adapt to climate change.

"These findings are strong evidence that investors are not getting the information they need ... even from industries facing clear, immediate risks from climate change," the report said. Only a handful of the companies provided an adequate account of the potential costs, it found – despite growing demands from financial regulators to disclose the risks of climate change.

The study by the Corporate Library analysis firm was based on information provided by the firms to the US regulatory authority, the securities and exchange commission, in the first quarter of 2008.

The lack of disclosure was most striking in the insurance industry, the report found. Despite evidence of the increasing severity of tropical storms – and the huge spike in claims following Hurricane Katrina in 2005 – 18 of the 27 firms made no mention of climate change or related risk in their financial disclosure forms.

Twenty-four of the 27 companies failed to mention any actions taken to address global warming – even though the report said there were now opportunities for climate change-related insurance policies.

Oil and gas companies did not even provide the bare minimum of information on climate risk, the study found. All but one of the 23 firms surveyed received only a "poor" or "limited" grade in disclosing climate risks. Seventeen of the companies gave no information on their emissions or their positions on climate change. The report singled out the oil and gas companies Exxon Mobil, Apache and Anadarko for weak disclosure.

Electricity firms did only slightly better. Even so, only three of the 26 firms surveyed gave an adequate assessment of the risks posed by climate change. Two provided information about their attempts to address climate change.