US insurers have been too slow to recognise the impact of climate change on their business models, according to a new report by ethical investment researcher Ceres.

It says only 11 of the 88 major insurers had formal policies to deal with climate change risks.

In a touch of irony, the report was to have been delivered at the National Association of Insurance Commissioners conference that had to be cancelled due to Hurricane Irene.

Ceres President Mindy Lubber says the findings were both “illuminating and disillusioning”.

“While the survey revealed a broad consensus among insurers that climate change will have an effect on extreme weather events, only a few insurers were able to articulate a coherent plan to manage the risks and opportunities associated with climate change,” she said.

On a more positive note, the survey found property and reinsurance companies are investing considerable resources in understanding the risks and developing strategies to drive more climate-resilient underwriting.

But small insurers are doing nothing. Ms Lubber says these insurers are often in the retail segment of the industry.

“While the survey reveals that most insurers are focused on the coastal impacts of climate change, this year’s events have revealed that climate risks extend far inland,” she said.

“According to the National Weather Service, before a single hurricane made landfall this year the US had already broken its yearly record for billion-dollar weather disasters and the cumulative tab from floods, tornadoes and heat waves has eclipsed $US35 billion ($33 billion).”

Ms Lubber says these trends have implications for the industry’s financial viability.

“If insurers don’t respond in a timely way to the business impacts of climate change, insurance availability and pricing could be affected – and with it the ability of consumers, businesses and government to productively employ capital.”