The meeting, which runs until Dec. 9, is the latest in a series to consider follow-up action to the 1997 Kyoto Protocol, which obligated industrialized countries to reduce greenhouse gas emissions by a specific amount. The Kyoto Protocol expires at the end of 2012, and the Durban encounter is considered crucial in forging an additional commitment period.
The goal of the talks organized by the U.N. Framework Convention on Climate Change is to cut greenhouse gases by 50 percent by 2050 and prevent temperatures from rising more than 2 degrees Celsius.
Honduran Cardinal Oscar Rodriguez Maradiaga, president of Caritas Internationalis, was leading a 20-person Caritas delegation to the Durban talks to press for an agreement on behalf of poor countries that have been severely impacted by climate change.
"Our climate is changing. Caritas organizations are responding to increasing unpredictability and extreme weather conditions experienced around the world. This year we saw floods in Central America, South and Southeast Asia and drought across East Africa," Cardinal Rodriguez said in a statement released by Caritas.
"Urgent action is necessary. Climate negotiators in Durban must not further delay agreeing to international legislation to curb the threat of climate change and set the world on a path to a more just and sustainable future," he said.
In 2011, East Africa suffered the worst drought in half a century. Caritas noted that drought was not new in East Africa, but said changes in weather patterns combined with lack of investment, competition for land and water have eroded the capacity of local people to cope.
"The whole world is vulnerable to climate change, but poor countries are affected more," Cardinal Rodriguez said. "Africa is one of the most vulnerable continents to the impacts of climate change. Africans are taking a stand in Durban; it is time for the world to stand with Africa."
Before leaving for Durban, Cardinal Rodriguez took several thousand young Italian members of a Franciscan environmental group to the Vatican for a lively encounter with the Pope.
The Pope told them that the church's teaching on the environment follows from the principle that men and women are collaborators with God and his creation. The lessons of responsible stewardship over natural resources are increasingly important, he said.
"In fact, it is by now evident that there is no good future for humanity or for the earth unless we educate everyone toward a style of life that is more responsible toward the created world," he said.
He said education toward environmental responsibility must begin in families and schools and must reflect the church's teaching that respect for the human being -- in all stages of life -- goes hand in hand with respect for nature.