President Donald Trump has undone or renegotiated many of his predecessor’s environmentally friendly policies, removing climate change research from government websites and pulling out of the Paris climate agreement. Religiously inspired environmental activists have emerged as some of his loudest critics.

William Gail is a meteorologist and past president of the American Meteorological Society. He is the author of Climate Conundrums: What the Climate Debate Reveals About Us, which examines, in part, the objections of some religious groups to climate change science. He is co-founder and chief technology officer of Global Weather Corp. in Boulder, Colo.

The Pontifical Academy of Sciences is the scientific office of the Roman Catholic Church and is located at the Vatican. It has multiple goals, including promoting the progress of the mathematical, physical and natural sciences and the study of related epistemological questions and issues. Members include scientists, clergy and laypersons. Werner Arber is president.

Rachel Hart Winter is the director of the Siena Center at Dominican University in River Forest, Ill. Her research focuses on Catholic ecological ethics, particularly on access to clean water as a fundamental human right. Contact via Tina Weinheimer, assistant director of public relations and communications for the university.

The Catholic Church, environmentalists and many ecology activists have high hopes for the encyclical, but others worry that the pope’s approach will be misguided.

The Center for Earth Spirituality is a ministry of the School Sisters of Notre Dame in Mankato, Minn. The center promotes awareness and ways of living that support the interdependence of all life. Contact is Lisa Coons.

Environmental Ministries of Southern California is based in San Diego and works with local congregations to highlight the spiritual and religious aspects of environmental issues through outreach, political advocacy, networking and programs. Contact the Rev. Peter Moore-Kochlacs.

Michael Pasquier is an associate professor of philosophy and religion at Louisiana State University in Baton Rouge, where he specializes in the history of religion and culture in the U.S. He teaches courses on religion and cinema, religion in Louisiana and religion in Southern culture, as well as a course on American Catholicism.

Robin Globus Veldman is a visiting scholar at Texas A&M University. She studies the relationship between religion and the environment, with a focus on American evangelicalism.