NCAR National Center for Atmospheric Research
Participate in a weather experiment to understand convection.
Learn that tornadoes are formed because of differing air pressures in the sky and on the ground.
Thunderstorms happen when a convection cell of rising and falling warming and cooling air creates clouds and condensation. Lightning accompanies these storms because as water crystals fly up into the cloud, it becomes polarized, with the top of the cloud positively charged and the bottom negative. An electron stepladder is expelled from the cloud and attracted to the earth below it.
Snowstorms require below-freezing temperatures, moisture in the air, and warm air rising above cold air to form.
Explore the cloud exhibit, in which condensed water vapor pools into the large basin. What kind of shapes can you make? What is happening to the water vapor as new shapes are made, and what does this have to do with the electrical bonds between the water molecules?