By Alex Emslie
California’s current drought is pretty exceptional — like the driest in about a millennium — according to an article published today in the journal Geophysical Research Letters by scientists with the University of Minnesota and Woods Hole Oceanographic Institution in Massachusetts.
But how could they know that? There weren’t a lot of rain gauges in California in 800 A.D. — at least, not the plastic kind.
So authors Daniel Griffin and Kevin Anchukaitis looked to tree-ring samples from California blue oaks.
“California’s old blue oaks are as close to nature’s rain gauges as we get,” said Griffin, a NOAA Climate and Global Change Fellow with Woods Hole Oceanographic Institution. “They thrive in some of California’s driest environments.”