- Nov 30, 2006Two and a half billion years ago, photosynthetic organisms started releasing oxygen into the atmosphere, changing the balance of gases on Earth. But researchers have long been puzzled as to how the organisms could make that oxygen without poisoning themselves. Now, two groups of
- Oct 28, 2006What caused the Permian-Triassic extinction, the largest mass extinction in Earth's history? The most likely explanation for the disappearance of up to 90 percent of species 250 million years ago, said David Bottjer of the University of Southern California, is that "the earth got
- Mar 4, 2006New research into a missing link in climatology shows that the Earth was not overcome by a greenhouse period when dinosaurs dominated, but experienced rapid fluctuations in temperature and sea level change that resulted in a balance of the global carbon cycle. The study is
- Sep 17, 2005Open University researchers have uncovered startling new evidence about an extreme period of a sudden, fatal dose of global warming some 180 million years ago during the time of the dinosaurs. The scientists' findings could provide vital clues about climate change happening today and in
- Sep 11, 2005Using primitive meteorites called chondrites as their models, earth and planetary scientists at Washington University in St. Louis have performed outgassing calculations and shown that the early Earth's atmosphere was a reducing one, chock full of methane, ammonia, hydrogen and water vapor.
- Aug 30, 2005Scientists from the Australian Antarctic Division, the University of Western Ontario, the Aerospace Corporation, and Sandia and Los Alamos national laboratories found evidence that dust from an asteroid burning up as it descended through Earth's atmosphere formed a cloud of micron-sized particles.
- Aug 12, 2005A number of hypotheses have been used to explain how free oxygen first accumulated in Earth's atmosphere some 2.4 billion years ago, but a full understanding has proven elusive. Now a new model offers plausible scenarios for how oxygen came to dominate the atmosphere.