Pope Francis
Stop killing our 'sister,' says Pope Francis in draft encyclical Getty

The "bulk of global warming" is caused by human activity and people must reduce consumerism and change dependence on fossil fuels to save "sister Earth," says an astounding, far-reaching leaked draft encyclical from Pope Francis.

The draft encyclical, or papal teaching letter, was supposed to be released Thursday, but was printed in full online by Italian publication L'Espresso.

Although Francis states that there may be some natural reasons for climate change, he blasts those who claim it is unrelated to human activity, saying "plenty of scientific studies point out that the last decades of global warming have been mostly caused by the great concentration of greenhouse gases (carbon dioxide, methane, nitrogen oxide and others) especially generated by human action," states a translation of a part of the 192-page encyclical Laudato Si or Praised Be by the Washington Post.

Francis cites "a very considerable consensus that we are now facing a worrisome warming of the climate."

The pontiff also decries the "attitudes hindering the paths toward a solution, even among believers [that] go from negating the problem to indifference, to an easy resignation, or to a blind faith in technical solutions."

He refers to the earth as "sister." This "sister protests the harm that we cause her. We've been raised to think that we were her owners and dominators, that we were entitled to plunder her," he writes.

Francis blames global warming in part on "the intensive use of fossil fuels," and he calls for "urgent action" to develop policies to reduce greenhouse gases, including "substituting fossil fuels and developing renewable energy sources."

The Vatican pleaded with reporters to honor the Thursday embargo, and a spokesman said the draft released was only an "intermediate" document.

Observers are awaiting an official Vatican translation into English and are eager to examine any changes between the draft and a final version.

Depending on what the final version says, it could have a huge influence on how the world addresses climate change — and could impact the upcoming American election among Catholic voters.

The Vatican has never before issued an encyclical devoted solely to the environment.