United Nations

The world will see mass migration, destabilized countries and starving people in the next 12 to 18 months without billions of dollars more funding, the U.N. World Food Program chief warned.

The U.N.'s humanitarian aid and refugee agencies are seeking $5.6 billion to help millions of people in Ukraine and countries that have taken in fleeing Ukrainians in the wake of Russia's invasion.

The ozone layer is a thin shield in the stratosphere that protects humans and the environment from harmful levels of the sun's ultraviolet radiation.

The most significant part of the U.N. pact is a commitment to protect 30% of land and water considered important for biodiversity by 2030, up from 17% of terrestrial and 10% of marine areas.

About half the world isn't covered by early warning systems that send alerts for weather emergencies. The worst is in developing countries, which have been hit hardest by global warming.

Secretary-General Antonio Guterres warning that the world is "on a highway to climate hell" and urged the two biggest polluting countries, China and the United States, to work together to avert it.

"The world had its say," Ukrainian President Volodymyr Zelenskyy said, calling Russia's push for annexation "worthless."

As leaders gather for the first all-in-person General Assembly since the pandemic, the war in Ukraine is a major focus. Secretary-General António Guterres has warned this is a time of "great peril."

U.N. Secretary-General Antonio Guterres appealed to the world to help Pakistan after arriving in the country Friday to see climate-induced devastation from months of deadly record floods.

It's not the first time for such a dire warning. Here's a brief look at why Guterres and others are raising the alarm now.