Rather, he provided some simple information on water vapor and clouds in the atmosphere and outlined some of the difficulties so-called Global Atmospheric Models have encountered. His remarks, and questions he hoped the audience would raise, may spark a new approach to the modeling difficulties, he said. Randall likened the event to bringing together the great mathematician John von Neumann and popular television weatherman Willard Scot to discuss water vapor, clouds and how to represent them in numerical form. For example, water tends to be very lumpy. As soon as air enters a cloud its motion becomes turbulent, and that, too, is a real problem-causer for mathematical modeling.
Water is crucial in energy absorption and transfer.
Evaporating a kilogram of water takes about the same amount of energy as burning 25,000 100-watt light bulbs for one second. Meanwhile, water condenses into clouds, warming up the atmosphere. Thunderstorms in particular, Randall said, move water and energy around in the troposphere, the five to 10 miles of air above the earth's surface in which weather takes place. A thunderstorm is like an express elevator, and thunderstorms have a tremendous effect on the flow of energy through the atmosphere. Clouds reflect sunshine back to space, cooling the planet off, but by trapping infrared, clouds can heat the planet.