TED Radio Hour: The Big Five

What are the five biggest global challenges we face right now -- and what can we do about them? on this weeks show, TED speakers explore some radical solutions to these enduring problems.

To tackle climate change, geoengineer Tim Kruger is developing technology that could remove large quantities of CO2 from the atmosphere. But he says it takes unprecedented cooperation to make it work.

There are more refugees in the world today than at any other time since World War II. David Miliband says each of us has a moral obligation to help solve this crisis by turning empathy into action.



Political instability is on the rise. Political scientist Ian Bremmer argues it's because world powers like the U.S. are abandoning their leadership roles, and creating a power vacuum.


Data analyst Sara Menker believes we could be less than a decade away from a global food crisis. She says Africa can help meet the world's growing demand for food.




Historian Rutger Bregman says a lack of cash is the cause, not the symptom, of poverty. He proposes a simple but radical solution: give those in need a guaranteed basic income.