Scientists fear warming is driving a collapse in the ocean currents that shape climate far and wide. The ice-choked waters off Greenland might hold the key.
Scoresby Sound, a fjord in eastern Greenland, as seen from the research ship.
Blooms of yellowish-brown seaweed along the Equator are breaking records and defiling beaches, while a centuries-old patch farther north is disappearing.
ยฉ Paola Chiomante/Reuters
Mexican National Guard members during a sargassum seaweed cleanup event in Cancun, Mexico, in June.