Schellnhuber also participated in the preparatory meeting entitled "Protect the Earth, Dignify Humanity – The Moral Dimensions of Climate Change and Sustainable Humanity", which was organized by the Pontifical Academy of Sciences in coordination with the Pontifical Academy of Social Sciences, the Sustainable Development Solutions Network, and Religions for Peace. The declaration signed by all organizers states: "The world should take note that the climate summit in Paris later this year (COP21) may be the last effective opportunity to negotiate arrangements that keep human-induced warming below 2°C (…) Political leaders of all UN member states have a special responsibility to agree at COP21 to a bold climate agreement that confines global warming to a limit safe for humanity (…)".
In its special report entitled "Climate Protection as a World Citizen Movement" published in 2014, WBGU already mentioned the increasing concern of the churches about the slow progress of climate negotiations and drew attention to their efforts, as a part of civil society, to influence climate policy.
The Pope is planning to address the UN General Assembly in New York in September, when the new Sustainable Development Goals (SDG) are to be adopted. In its current policy paper "Human progress within planetary guard rails – A contribution to the SDG debate", the WBGU makes the case for integrating the planetary guardrails into the SDGs in order to protect humanity’s natural life-support systems.