Murdoch’s tweet is sure to raise the ire of environmentalists, many of whom take it as a given that rising concentrations of carbon dioxide in our air have been horrible for the environment.

Indeed, the U.S. Environmental Protection Agency classifies rising carbon dioxide emissions as a “pollutant.”

But that wasn’t the media mogul’s only shot at the environmentalists today. He criticized another green sacred cow: government investment in renewable energy.

He later clarified that not all renewable energy projects are uneconomic, just some of them:

Update: Murdoch cites his source:

The article Murdoch is referring to was published in the January 4, 2013, edition of the Wall Street Journal.

Did you know that the Earth is getting greener, quite literally? Satellites are now confirming that the amount of green vegetation on the planet has been increasing for three decades. This will be news to those accustomed to alarming tales about deforestation, overdevelopment and ecosystem destruction.

The inescapable if unfashionable conclusion is that the human use of fossil fuels has been causing the greening of the planet in three separate ways: first, by displacing firewood as a fuel; second, by warming the climate; and third, by raising carbon dioxide levels, which raise plant growth rates.