ATM OCN 100 Study Guide - Midterm Guide: Ico, Altocumulus Cloud, Stratus Cloud
30 Oct 2014
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Midterm two review- weather and climate: precipitation- any liquid or solid water particle that falls from the atmosphere and reaches the ground. It"s too difficult for drops to condense together: 100% relative humidity needed for h2o drops to grow but rh is almost never 100, collision-coalescence process- cloud particles bump into each other and merge together or coalesce. This process is much quicker than condensation: water droplets in clouds with different sizes move at different speeds, as gravity and vertical motions act on them. The difference in speed increases the chance of collision: a large water droplet in motion can create an air current around it that can be strong enough to force tiny droplets to flow around it and not collide. This reduces the probability that the droplets will collide: once a droplet grows to a size where the downward force of gravity exceeds the updraft force of air currents, it falls downward through the clouds.
