Weather on the Earth

When the Voyager spacecraft passed Neptune in 1989, it had taken pictures of the 4 gas giant planets (Jupiter, Saturn, Uranus, and Neptune). These planets are huge rotating balls of gas and liquid that all rotate faster than Earth. Jupiter and Saturn spin in 10 hours! What the planetary scientists learned from the Voyager mission is that the spin of the planet is the all-important feature that determines and organizes weather. As I sit at my computer, putting this material together, the sky to the west looks threatening. Mammatus clouds on the horizon hint at stormy weather ahead, and the lightning off to the distance promises some excitement. I took my camera outside to get some pictures of the local weather, and have included them below. I enter them into my course because they are initerestng, and open the door to a discussion on weather.

Why is it that one night, the storm hits with a fury, and the next night the sky is beautiful? The bolt of lightning hit just a block away from our house, and the next evening the sunset showed beautiful crepuscular rays. In the image pair below, the sunset was spectacular, and got even better as the sun sunk further to the west. The sky turned ugly during another evening, winds came up from what seemed like nowhere and blew rain and sleet all over the place. This storm blew boats right out of the water and over a differenc cabin on another lake, depositing them deep in the woods 150 away! The winds were estimated at 100 miles per hour.


What causes lightning? What causes beautiful sunsets? Where does the wind come from? How can hail fall down in summer? If these questions plague you, then I hope these pages will bring some answers. Have fun learning some of the basic information about weather. The material contained in this section of the course is from the University of Illinois.

Air Masses & Fronts

Clouds & Precipitation

El Nino

Forces & Winds

Severe Storms

Weather Forecasting

You can go ahead to Air Masses and Fronts now, or return to the Earth-Science Introduction.

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