Weather - How did weather get started? Why does it rain and snow? Why does the wind blow?
Welcome to Quatr.us Study Guides!

Weather

Thunderstorm
A thunderstorm in South Africa

The weather on Earth happens because of the evaporation and condensation of water, and because of the spinning of the earth and the tilt of the earth on its axis. Does it seem strange that such quiet things could cause big thunderstorms and huge waves and blizzards? Here's why.

Because the Earth is tilted on its axis, the northern and southern parts of the Earth are sometimes closer to the Sun and sometimes farther away. This causes the seasons - spring, summer, winter, and fall. In the winter, if you are far enough north or south, it gets cold enough for rain to fall as snow. In the summer, if you are close to the equator, it gets warm enough to warm up the ocean and cause hurricanes and typhoons.

Because the Sun's rays hit the Equator straight on, and only hit the North and South Poles at a slant, the Earth was always colder up near the North Pole and down near the South Pole, and it was always warmer near the Equator, just as it is today. Near the Equator, the hot air rises, because hot air is lighter than cold air. As the hot air rises, there's an empty area near the surface of the land or ocean. So cold air from the North and South Poles flows to the Equator to fill in that empty area. This movement of air is what we call "wind".

Because the Earth is spinning at the same time, the air doesn't flow straight north or south, but twists to the east or west. Air that is going towards the Equator twists to the west. Sailors call these winds the Trade Winds, and they're the winds that Columbus used to sail to North America.

Further north, or further south, the winds blow mainly to the east, instead: sailors call these winds the "westerlies", because they come from the west. Sailors used these westerlies to sail back to Europe from North America, or from Europe to Australia and New Zealand. Then at the North Pole and the South Pole, the winds blow mainly to the west again, and sailors call them "easterlies."

Bibliography and further reading about the atmosphere:

Learn by Doing - Clouds
More about clouds
More about Thunderstorms
More about Weather
Quatr.us home


Celebrating Black History Month with the pharaoh Hatshepsut, the queen Shanakdakhete, the poet Phillis Wheatley, the medical consultant Onesimus, the freedom fighters Toussaint L'Ouverture, Denmark Vesey, Yaa Asantewaa, and Samora Moises Machel, and the civil rights leader Martin Luther King, Jr.
Please help other teachers and students find us: link to this page from your class page.
Karen Carr is Associate Professor Emerita, Department of History, Portland State University. She holds a doctorate in Classical Art and Archaeology from the University of Michigan. Follow her on Instagram or Twitter.
Cite this page
  • Author: K.E. Carr
  • Title:
  • Site Name: Quatr.us Study Guides
  • Publisher: Quatr.us
  • Date Published:
Proud of your class page, homework page, or resource page? Send it in and win a Quatr.us "Great Page!" award!
Sign up for more free articles and special offers in Quatr.us' weekly newsletter:
We will never share your e-mail address unless you allow us to do so. View our privacy policy. Easy unsubscribe links are provided in every email.
Comment on This Article

Cool stuff we've been enjoying: Looking for birthday gifts? Check out these new Chromebooks - all the computer you need for only $229.00!. Then study in peace with these Beats wireless headphones - for the exact same price! When you're done, show off your presentation or watch a movie with this excellent smartphone projector for only $39.99!


Does your class page honor diversity, celebrate feminism, and support people of color, LBGTQ people, and people with disabilities? Let us know, and we'll send you a Diversity Banner you can proudly display!
Looking for more?
ADVERTISEMENT
Quatr.us is loading comments...
(Comments will appear after moderation, if they are kind and helpful. Feel free to ask questions, and we'll try to answer them.)
Cite this page
  • Carr, K.E. . Quatr.us Study Guides, . Web. 27 February, 2017
ADVERTISEMENT