Al Gore is warning you: Investing in fossil fuels will hurt your bottom line as countries begin to issue tougher regulations to fight global warming.

The Gore-founded Generation Investment Management put out a report saying that investing in fossil fuels will not be as profitable going forward because of political pressures to fight global warming.

In order to meet the United Nation’s target of limiting global warming to 2 degrees Celsius, Generation says that about two-thirds of unextracted fossil fuels — such as coal, oil and natural gas — must stay underground. This means that fossil fuel assets like coal mines or oil and gas wells must lower production, reducing revenues.