And are conservation groups moving into the business of giving investment advice?

It seems an unlikely path for environmentalists to take, but this WWF commissioned report warning that failure to take carbon risk into account could knock pension fund returns raises some interesting points.

"Carbon Risks in UK Equity Funds" by Mercer and Trucost "outlines how fund manager complacency on corporate carbon performance could put pension fund assets at risk as carbon-intensive companies face rising carbon costs and their company valuations fall in the short-term in anticipation of future carbon risk".

The report argues that fund managers "could dramatically reduce the carbon footprints of their funds through stock selection without the need to alter sector weightings or their overall investment strategy".

It also encourages them to engage with companies in their portfolios and calls on them to support mandatory reporting requirements for corporate greenhouse gas emissions.