Timothy M. Lenton

TL;DR: In this article, the authors proposed a new approach to global sustainability in which they define planetary boundaries within which they expect that humanity can operate safely. But the proposed concept of "planetary boundaries" lays the groundwork for shifting our approach to governance and management, away from the essentially sectoral analyses of limits to growth aimed at minimizing negative externalities, toward the estimation of the safe space for human development.

TL;DR: Identifying and quantifying planetary boundaries that must not be transgressed could help prevent human activities from causing unacceptable environmental change, argue Johan Rockstrom and colleagues as discussed by the authors, who identify and quantify planetary boundaries.

TL;DR: It is explained how, in principle, early warning systems could be established to detect the proximity of some tipping points, and critically evaluate potential policy-relevant tipping elements in the climate system under anthropogenic forcing.

TL;DR: The risk that self-reinforcing feedbacks could push the Earth System toward a planetary threshold that, if crossed, could prevent stabilization of the climate at intermediate temperature rises and cause continued warming on a “Hothouse Earth” pathway even as human emissions are reduced is explored.