Climate

The Dead Sea, a landlocked lake bordered by Israel, Jordan and Palestine, is nearly 10 times saltier than the ocean. And it’s getting saltier. Since the beginning of the 20th century, the water level has dropped by nearly 30 meters, largely because of diversions of the Jordan River, the lake’s primary tributary and the arid region’s main source of fresh water.

Some large meteorite strikes leave obvious craters on Earth’s surface, while others that hit water or ice or explode in the air may only leave subtle markers in the soil, such as exotic minerals or elevated levels of rare elements like platinum or iridium. In a new study, researchers report spikes of platinum in sediments at archaeological sites across North America, offering new evidence, they suggest, of a major meteorite strike about 12,800 years ago, just before the onset of a global cold period known as the Younger Dryas. The lack of a telltale crater dating to this time, however, has left scientists debating for years whether an impact actually occurred and what, if any, role it had in setting off the cold snap and affecting some of Earth’s human and animal populations.

Rapid, climate-driven shifts in monsoon patterns may have shaped ancient Chinese societies, according to new research. And their history could be our future.

The A.D. 1257 eruption of the Indonesian volcano Samalas sent an ash plume an estimated 43 kilometers into the sky in one of the most sulfur-rich eruptions of the last 7,000 years. A new study using tree rings, ice cores and historical records investigates how this colossal eruption impacted climate across the Northern Hemisphere, finding that the eruption triggered severe cold in some regions, while other areas were less affected. The pattern could be explained by the behavior of sulfate particles in the atmosphere, researchers suggest.