On Monday, Pope Benedict XVI shook the world with news of his resignation. But during the course of his seven years as pope, he sought to affect the planet through conservation of its resources.
Deemed the "green pope" by many, Benedict, 85, has spoken often of the need for greater care for creation among Catholics, Christians and people of all faiths around the world.
His voice in the environmental movement has emphasized the environment as a gift from God, and that its protection in the present and conservation for the future are a moral requirement. Under Benedict, the Vatican has gone as far as declaring pollution among the "social" sins  impacting the modern world.
In its Feb. 13 newsletter, the Catholic Coalition on Climate Change highlighted Benedict's reaffirmation of many traditional ecological church teachings, including "the giftedness of creation, the vocation of stewardship and the universal destination of created goods." They also cited his advocating on issues such as an international climate treaty and renewable energy technologies, as well as attention to environmental refugees.
David Cloutier, an associate professor of theology at Mount St. Mary's University, in Emmitsburg, Md., said the foundation for Benedict's ecological vision is the idea of nature as an expression of love and truth.
As the pontiff developed his "theology of the earth," he viewed the environmental movement as an entry point for re-evangelizing secular society, Cloutier said, that the church and society share "a commitment to a moral order that precedes us."
"At the heart of Benedict's environmental theology is not simply a concern over actual harms, but of a pattern of life that violates the order inherent in creation," Cloutier wrote in a paper he presented at the November Catholic climate conference  in Washington.
Most notably, Benedict focused his 2010 World Day of Peace message specifically to the message of conservation as a moral requirement and a path to peace. Titled "If You Want to Cultivate Peace, Protect Creation," Benedict spoke of addressing the environment as a pivotal step toward ending human conflict:
"Respect for creation is of immense consequence, not least because 'creation is the beginning and the foundation of all God's works,' and its preservation has now become essential for the pacific coexistence of mankind. Man's inhumanity to man has given rise to numerous threats to peace and to authentic and integral human development — wars, international and regional conflicts, acts of terrorism, and violations of human rights. Yet no less troubling are the threats arising from the neglect — if not downright misuse — of the earth and the natural goods that God has given us. For this reason, it is imperative that mankind renew and strengthen 'that covenant between human beings and the environment, which should mirror the creative love of God, from whom we come and towards whom we are journeying."
In the address, the pontiff listed a variety of ecological problems: climate change, deforestation and desertification, polluting of rivers and aquifers, a loss of biodiversity and increased natural catastrophes. But to engage such issues, Benedict pointed toward first examining the relational ties among economic decisions, ecological stewardship and compassion for others.
While he didn't denounce technological advances and development, the pope said they must account for the environmental — and human — impact of such economic decisions.
"There is a need to act in accordance with clearly-defined rules, also from the juridical and economic standpoint, while at the same time taking into account the solidarity we owe to those living in the poorer areas of our world and to future generations," he wrote.
He called attention to the greater responsibilities of industrialized nations (to encourage low-waste lifestyles and help developing nations implement low-impact, sustainable solutions), and said the motivator for environmental action "must be the quest of authentic world-wide solidarity inspired by the values of charity, justice and the common good."
"God gave men rule as steward and administrator with responsibility over creation, a role which men must certainly not abuse, but also one which he may not abdicate," he said.
Aside from his writings, Benedict oversaw the implementation of numerous sustainable and energy-efficient projects during his pontificate. In Sept. 2008, the Vatican began installation of 2,700 solar panels  on the roof of the Paul VI auditorium. A year later, the city-state announced plans for building Europe's largest solar power plant, estimated to cost $660 million.
In 2010, the Vatican newspaper declared Vatican City as the world's greenest state , producing 200 watts of solar energy per inhabitant. No doubt that its minute population (900) and small geographic footprint (.2 square miles) aided its case; in comparison, Germany, second in solar per-capita at the time, produced 80 watts per inhabitant.
Benedict has also made a point of speaking or releasing statements before international climate and sustainability conferences convene, most recently in June before the Rio +20 Conference on Sustainable Development, held in Rio de Janeiro, Brazil.
Last year, an auto design contest asked student designers to create a popemobile that met low-emissions standards, in addition to safety and visibility requirements. While Benedict has made it known he wished to replace a gas-fueled popemobile with one powered by sunlight, the new model presented to him by Mercedes Benz in December lacked additional energy efficiency standards.
With two weeks remaining in his papacy, it's unlikely Benedict will oversee any additional eco-friendly upgrades at the Vatican. But perhaps his last green contribution will come by way of ensuring a greenhouse-gasless smoke announces his successor.
[Brian Roewe is an NCR staff writer. His email address is firstname.lastname@example.org.]