PCB pollution threatens to wipe out killer whales

More than 40 years after the first initiatives were taken to ban the use of PCBs, the chemical pollutants remain a deadly threat to animals at the top of the food chain. A new study shows that the current concentrations of PCBs can lead to the disappearance of half of the world’s populations of killer whales from the most heavily contaminated areas within a period of just 30-50 years.

In pictures: Millions mark World Cleanup Day 2018

Cleanups were organised in 152 countries around the world, with results from just 75 countries on Saturday night already confirming the participation of more than 14.5 million people. Full results of the day, including the amount of waste collected, were set to be released on Sunday.

Summer Ship Tracks in the Pacific

The large number of ships traversing the North Pacific, combined with all of the low clouds, make ship tracks more common here than anywhere else in the world. Roughly two-thirds of the world’s ship tracks are found in the Pacific.