Julia Steinigeweg—Agentur Focus/Redux

Sweden has produced two of the most important figures in the fight to save the planet’s climate. If most of the world knows Greta Thunberg, the scientific community is just as familiar with Johan Rockstrom. Director of the Potsdam Institute for Climate Impact Research, Rockstrom helped pioneer the concept of “planetary boundaries,” environmental guidelines and limits that people need to operate within in order to keep humanity safe. His team has identified nine we shouldn’t cross, including not just heating the earth, but also acidifying its oceans and degrading its ozone layer. Currently, we’re crashing quickly through these red lines, which, according to Rockstrom, merits the urgent need to create “new business models that focus on circularity, regeneration, and justice.” His work is crucial to understanding the interconnected crises facing our planet and is shaping the path forward, guiding leaders on how to turn complex science into clear, quantifiable actions.

McKibben is an author and an environmentalist

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