Some argue that we have a moral responsibility for future generations, but others ask: how do we know what they would want? Writer Charles Mann explores the confusing ethics of acting on global warming.

While some world leaders resist global cooperation, city leaders are working across borders to tackle big issues like global warming, immigration and terrorism, says urban expert Robert Muggah.

Not every conversation with a climate denier has to lead to raised voices and hurt feelings. Here’s how to do it constructively.

The loss of polar ice may seem like an abstract concern, but it’s one that will affect all of us, no matter where we live, says glaciologist and TED Fellow Michele Koppes.

How can you protect crops against global warming? One answer: find the secrets of plants that already thrive in the most punishing climates, says microbiologist Rusty Rodriguez.

How two Australian sisters channeled their love of STEM and coral reefs into the most glorious participatory art project.

Cities are the the 21st century’s dominant form of civilization — and they’re where humanity’s struggle for survival will take place. Robert Muggah and Ben Barber spell out the possibilities.