Tens of millions of trees in California are now at risk because of sustained drought, according to new research. And a different study in a different journal foresees a parched future for the evergreen forests not just in the Golden State but in the entire US southwest.
Gregory Asner of the Carnegie Institution for Science in Stanford, California and colleagues used airborne, laser-guided imaging instruments to measure, for the first time, the full impact of California’s four-year drought, and combined their measurements with satellite data going back to 2011. What they were looking for, precisely, were the levels of water content in the forest canopy.
They report, in the Proceedings of the National Academy of Sciences, that 58 million Californian trees – pines, firs, hemlocks, juniper, sequoia and so on – are now suffering losses “extremely threatening” to long-term health.