The Canadian prime minister argued in a UN speech that COVID-19 is a "wake-up call" that current global systems simply don't work anymore.
The Swedish climate activist has responded to two controversies as she travels home to Sweden for the holidays.
The president mocked the teen activist on Monday: “She seems like a very happy young girl looking forward to a bright and wonderful future.”
"You have stolen my dreams and my childhood with your empty words," the 16-year-old told the United Nations gathering.
Presidents Donald Trump and Jair Bolsonaro have forged a nationalist alliance based on the idea that climate change is a hoax.
Iran’s president Hassan Rouhani separately promised to unveil a regional peace plan at this week's upcoming high-level meetings at the United Nations.
The day of protest precedes the United Nations summit on how to rein in the worst effects of climate change.
World population could reach a peak of nearly 11 billion around the end of the century.
Their answers are terrifying.
China, India and the U.S. rank among the biggest contributors to the problem.