New measurements show a dramatic decline in the health of glaciers and sea ice, perpetuating the cycle of warming.
Deadlock stymied a third East Antarctica protection plan. Only twice before has the panel created marine protected areas.
Droughts, floods and heatwaves drove food insecurity and mass migration as communities on every continent were hit by massive costs, the World Meteorological Organization said.
Scientists say the Arctic region is warming about twice as fast as the rest of the planet, but the Trump administration blocked a council statement from referring to that threat.
The Event Horizon Telescope pulled off one of astrophysicists' longtime dreams by documenting a supermassive black hole.
A new scientific assessment shows damage to the ozone layer from aerosol sprays and coolants started recovering in parts of the stratosphere with bans on ozone-depleting substances.
Concerns about climate change's rapid rate of advance in the far north drove three years of talks on commercial fishing.