Penn State researchers mapped microplastics in three Pennsylvania watersheds, Raystown Lake, Conemaugh River Lake and the John Heinz National Wildlife Refuge near Philadelphia, and found them almost everywhere. Sediment cores showed that microplastic concentration has roughly doubled about every 20 years since 1950, closely tracking global plastic production, which now exceeds 500 million tons a year. Surprisingly, the rural forested Raystown watershed had levels similar to the urban Philadelphia site, so land use alone could not predict contamination. The most common types were polypropylene, polyurethane and tire rubber, many from single-use products. The team dated sediment layers using lead-210 and cesium-137, the latter marking the 1964 peak of nuclear weapons testing. Estuaries trap some plastic, but not enough to explain the ocean's so-called missing plastic. The study also found a small decline in concentration in the most recent layers, which the authors suggest may reflect better recycling and greater public awareness. The findings show that plastic accumulates in rivers and lakes long before it reaches the sea, and that the trend is at least partly responsive to human b…

Israeli reports also say the cabinet directed the military to prepare for a possible new attack on Iran.

Angkor, near Siem Reap in northern Cambodia, was the capital of the Khmer Empire, which ruled much of mainland Southeast Asia between roughly the 9th and 15th centuries. At its height the city spread across about 3,000 square kilometres, making it the largest pre-industrial city on Earth by area. Its growth depended on water: huge reservoirs called barays, along with canals and embankments, stored monsoon rain and carried it to rice fields. That system let farmers harvest more than once a year and fed a very large population through the dry season. The temple complex of Angkor Wat, built in the early 12th century, is the best-known monument and still stands at the heart of the park.