It raised the obvious problem that if tree rings were not detecting the modern warming trend, they might also have missed comparable warming episodes in the past. (steynonline.com)
Global climate is a good example — not today's global warming episode, but long - term climate changes on the scale of many millions of years. (realclimate.org)
In the current warming episode, it is clear that CO2 and other human - induced heat - trapping gases are driving the warming. (climatecommunication.org)