Some 500 religious leaders and climate scientists recently signed a joint appeal for climate action, noting that “climate change is an ecological and moral emergency that impacts all other aspects of our shared lives and requires us to work together to protect our common home.” This call for action follows the international recognition in the Paris Climate Agreement, ratified in 2015 by 175 countries, of the pending disaster that climate change poses for the planet and its people, especially the poor of all nations. It also emphasizes the need for a cooperative international effort to reduce green-house gases to safeguard the planet and its inhabitants. In this essay, we follow the “see, judge, act” model of Catholic social teaching to explore the issue of ecology and climate change.