Feed Science Daily: Polar Ice Clouds May Be Climate Change Symptom (sciencedaily.com)
As the late summer sun sets in the Arctic, bands of wispy, luminescent clouds shine against the deep blue of the northern sky. To the casual observer, they may simply be a curiosity, dismissed as the waning light of the midnight sun. But to scientists, these noctilucent ice clouds could be an upper-atmospheric symptom of a changing climate.