Below is a section of the introduction from A Bishops’ Letter about the Climate, which covers a multitude of critical environmental issues, from the 2014 Bishops' conference:
"We have lived with reports and forecasts of climate change since the 1980s. Our climate is the result of the interaction of complex systems and there is often a great distance between cause and effect in terms of both space and time. There are uncertainties and a lack of clarity. However, the knowledge we possess today does not allow us to postpone until tomorrow
what needs to be done now. Our human climate impact must decrease for the sake of the earth, for the sake of the world that God so loves that God gave us Jesus Christ."
The United States Government approved a rule that added regulations for NEPA and the United Conference of Catholic Bishops supports this change. The reason for the support is that they believe NEPA is vital for ecological and societal safety.