According to PBS News Hour, California’s four-year drought has killed millions of trees in the Sierra Nevada mountain range and has scientists worrying about the region’s giant sequoias. The famous thousand-year-old trees require more water than any other species on Earth, but warm conditions during the past two winters have reduced the snowpack that provides their main source of water. Sequoias pull water from the soil all the way up to the tops of the trees, according to University of California, Berkeley researcher Wendy Baxter. Examining how much tension the water is under as it travels upwards and into each leaf tells researchers the level of stress each tree is experiencing. The greater the pressure required to push the water out, the more stressed the tree becomes.
Conditions are currently warming up in the Pacific, and the NOAA Climate Prediction Center expects a greater than 90 percent chance that El Niño will continue through the winter and most likely into the spring. This image shows the July 13-19, 2015 sea surface temperature departure from the 1981-2010 average. Image by NOAA
This week’s news roundup takes us to San Francisco, where Ira is joined by KQED science and environment reporter Lauren Sommer. As California’s historic drought continues, many Californians have pinned their hopes on a larger-than-usual El Niño to dump much-needed water on the West. But as Sommer explains, there’s a new climate player in town that could muck up that plan: the Blob–scientists’ name for a mass of warm water in the North Pacific—which could divert those long-sought winter storms around the thirsty state.