Banks and regulators around the world are grappling with how to measure and manage the consequences a warming climate and alterations to energy policy will have for the financial system.

Banks, like every other commercial entity under the sun, work for investors too. And to expect them to merely cover their costs is to ask them and their investors to provide something for nothing.

Commercial lending accounted for about 60% of banks’ loan portfolios in 1982. It now makes up about 25% of current loan books ...