ENV221H1 Lecture Notes - Lecture 7: Ipcc Second Assessment Report, Permafrost, United Nations Environment Programme
Document Summary
Co2 in the atmosphere - glacial and interglacial periods. How do we currently understand the climate paradigm. Earth"s climate system is inherently chaotic, sensitively balanced, and threshold-laden . Can be stable for one time and then suddenly over the edge. The latest peer-review paleoclimatic studies suggest that current temperatures are not the warmest in earth"s history. Globally derived best estimates (ipcc) project a change of 1. 4 c - 5. 8 c over the next century. Such a change could cool down selective areas of the globe by 3-5 c , while simultaneously causing drought on other parts. The current pattern & rate of warmeth is unique in that it cannot be explained by any natural-focusing mechanism. Example: distance / angles between earth and the sun. The earth"s position and orientation relative to the sun (our orbit) varies, bringing us closer and farther away in predictable cycle. Variation in the 3 cycles are believed to cause the glacial cycles.
