Forces of Nature

Snow is nothing more than frozen water, and water is clear, not white. But snow is bright white. How?

By Allison Loudermilk

What is "wind chill"? Does it have any effect on inanimate objects?

They're an odd enough sight in the sky to make you do a double take. Ready for the "super cool" explanation behind hole-punch clouds?

By Allison Troutner

Iceland? The North Pole? Antarctica? There are a lot of super cold places on this planet, but which one can claim bragging rights as the coldest place on Earth?

By Mark Mancini

You’ve heard the warnings about thunderstorms: Stay out of the tub, unplug your TV and don’t call people from your land line. But can you really get struck by lightning while you’re inside?

The raging wildfires in southern California have claimed lives and destroyed hundreds of homes. Learn how wildfires start and spread, and find out what firefighters do to battle the blaze.

By Kevin Bonsor

Around 1,800 thunderstorms are occurring on the Earth at any given time. But how do they form, and what causes them?

We hear about humidity in just about every weather report on the nightly news. There are several different ways meteorologists measure humidity, but relative humidity is the most common measurement. What is relative humidity, though?

By Nathan Chandler

Flooding has claimed more lives than any other natural disaster. Find out how a gentle stream becomes a raging torrent.

By Tom Harris

Volcanoes are some of nature's most awe-inspiring displays, with everything from exploding mountaintops to rivers of lava. Learn how all the different types of volcanoes work.

By Tom Harris

An earthquake is one of the most terrifying phenomena that nature can dish up. We generally think of the ground we stand on as "rock-solid" and completely stable. An earthquake can shatter that perception instantly, and often with extreme violence.

By Tom Harris & Patrick J. Kiger

There's often a strong, quite pleasant, smell right after a rain shower. What accounts for petrichor, the 'smell of rain'?

By Kathryn Whitbourne & Desiree Bowie

How does the aurora borealis (the Northern Lights) work? What causes it? Why can you only see it in the North? Are the myths about it producing sound true?

By Austin Henderson

Do scientists really think a massive earthquake could break California in two?

Every night on the news, the weatherperson reports the UV index. What is the UV index and how is it calculated?

What causes the seasons? Why are the seasons reversed in the Northern and Southern Hemispheres? And if the Earth moves in an elliptical orbit around the Sun, why don't we have two summers and two winters every year?

By Sascha Bos

You may have heard that you can figure out how far away lightning is by how long it takes for the thunder to arrive after you see the flash. Is this true? How do you calculate it?

Why is it colder at the top of a mountain than it is at sea level? Heat rises, and the top of a mountain is closer to the sun, so shouldn't it be hotter at the top of a mountain?

By HowStuffWorks.com Contributors

Precipitation can vary from rain to snow when the temperature is below freezing. Why does precipitation not always fall as snow when it's below freezing?

We can usually see rainbows right after a rainstorm on a warm Spring day. These giant colorful arcs stand out against the dark rain clouds. Have you ever wondered what causes this phenomena? Find out how rainbows are created in this article from HowStuffWorks.

By Austin Henderson

A tornado is one of those amazing, awesome acts of nature that simply leaves you dumbfounded -- a huge, swirling, 200-mph beast of a storm that appears to have a mind of its own.

By Marshall Brain, Robert Lamb & Yara Simón

How often have you watched a weather forecaster point to a spiral-shaped cloudy mass with a sense of dread and fascination? What fuels these ferocious storms?

By Marshall Brain, Craig Freudenrich, Ph.D. & Robert Lamb

Lightning is an incredible force of nature. And like many natural phenomena, lightning is not always what it seems. Go behind the mystery and learn what's really going on when lightning strikes.

By John Zavisa & Jesslyn Shields

Tornado chasers generally stay about a mile away from the tornado itself -- but not IMAX cinematographer Sean Casey. He has built a Tornado Intercept Vehicle and hopes to withstand a direct hit. Check it out.

By Tracy V. Wilson

Learn how avalanches form, how long you can stay alive while buried under an avalanche and what steps you can take to survive.

By Tracy V. Wilson