Yahoo! News reposted this Space.com news report about how the Space Shuttle's exhaust plume created a 1300 square mile cloud formation over the South Pole. Before these clouds, called noctilucent clouds in the report, had been used to judge the degree of global warming because it was believed these clouds "are thought to be sensitive to the temperature and humidity of the atmosphere."
"Because the brightness, occurrence, and range of the clouds have been increasing, some scientists have suggested that they are indicators of global climate change," said Xinzhao Chu from the University of Illinois at Urbana-Champaign. "That role needs to be reconsidered, however, because of the potential influence of water vapor in shuttle plumes."
It just strikes me as odd how often lately the Global Warming movements "scientific" basis for complaint against industrialization continues to not have a leg to stand on. Sorta like my command of the English language.