BIOL 3450 Lecture Notes - Lecture 1: Water Cycle, Chemical Energy, Downwelling
Document Summary
Lecture 1 water world: where did our water come from, 2 theories: Volcanism: heat-driven chemical reactions in the mantle interior combined h and o2 to make water that continues to be released at the surface by volcanism: approximately 0. 1-0. 5% of mantle rick is water weight. This accounts for 3-16x the amount of water in the oceans right now: volcanoes (active or not) release 1000s of tons of gases into the atmosphere per day. Over 4 billion years, this could fill the oceans approximately 100 times. Comet hypothesis: ~ 20 comets of average 10kg mass hit out atmosphere each minute, equaling 10 million per year. 300,000 km3 moves between reservoirs per year: amount of water is approximately constant. Hydrological cycle must balance addition and removal: mixing, at the surface, wind causes horizontal mixing of waters, coriolis effect causes water to move clockwise and counter-clockwise in the northern and southern hemispheres respectively.