One of the speakers slated for the Vatican rollout of the long-awaited Papal document on climate change once said the earth is overpopulated by at least 6 billion people.

The teaching document, called an encyclical, is scheduled for release on June 18 at Vatican City. Perhaps with the exception of the 1968 encyclical on contraception, no Vatican document has been greeted with such anticipation.

The political left is hoping for a document that ties belief in global warming to a religious obligation. Climate skeptics have already started criticizing the document.

The choice of Professor John Schnellnhuber, founding director of the Postdam Institute for Climate Impact Research, as one of three presenters may be giving the left added hope and giving giving skeptics severe heartburn. He has been described as one of the more aggressive scientists on the question of man-made global warming.

In a talk given to what’s described as the “failed” 2009 Copenhagen climate conference, reported in the New York Times, Schnellnhuber, who has advised German President Angela Merkel and is a visiting professor at Oxford, said of global warming: “In a very cynical way, it’s a triumph for science because at last we have stabilized something –- namely the estimates for the carrying capacity of the planet, namely below 1 billion people.”

Schnellnhuber is also author of what’s called the “two-degree target” that says governments must not allow the temperature to rise more than 2 degrees higher than at the start of the industrial revolution. Any higher, the theory holds, and much life on earth would either perish or be gravely harmed.

To deal with climate issues, he has also called for an “Earth Constitution that would transcend the UN Charter” along with the creation of a “Global Council…elected by all the people on Earth” and a “Planetary Court..a transnational legal body open to appeals from everybody, especially with respect to violations of the Earth Constitution.”

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