Scientists Say They've Figured Out What Turned the Sun BlueThe Zavaritskii volcano caused significant global cooling in 1831, identified through ash analysis from polar ice cores.
Ancient Plant, Insect Bits Confirm Greenland Melted in Recent Geologic PastThe Greenland Ice Sheet melted in the past, causing a tundra landscape, showing it's more fragile than thought, and implying future risk from human-caused climate change.