Scientists skeptical about catastrophic global warming have long argued that the Earth is merely recovering from a centuries- long cold spell, and that current warming has more to do with natural causes then man-made emissions. Now comes additional ammunition for this idea in the way of a scientific study that examined tree rings in the Alps mountains to reconstruct summer temperatures for the last millennium. The study found that indeed, the planet was considerably warm from about 950 to 1350 A.D., followed by an extended cold period that lasted until 1850. As evidence for these distinctive warm and cold periods continue to emerge from place around the world, it appears there’s mounting reason to cool off the global warming hysteria.