1,000-Plus Years of Tree Rings Confirm Unprecedented Nature of 2021 Western North America Heat Wave
Lead author Karen Heeter takes a core sample from an old mountain hemlock near Crater Lake, Oregon, where at least one tree dated to the 1300s. Credit: Grant Harley/University of IdahoThe historic extremity of the event serves as a warning for other regions.During the summer of 2021, an unprecendented heatwave swept across western North America, affecting regions from British Columbia to Washington, Oregon, and beyond into other interior areas that typically experience a mild climate. Temperatures shattered records in…