Forces of Nature

Mount Vesuvius, located near Naples, Italy, is one of the world's most iconic active volcanoes, renowned for its historic eruption that buried Pompeii. Discover its history, significance, and natural beauty.

By Cristen Conger

The birds stop chirping, and the wind chimes are silent. This eerie calm that's invaded your neighborhood is just a temporary pause before the shrills and shrieks of the incoming storm.

By Jessika Toothman

You might think of weather as something that happens around your life. It could prevent you from taking a bike ride or inspire you grab an umbrella on your way out. But there's more to weather than its ability to thwart the best-laid plans.

By Robert Lamb

We tend to think of the ground beneath our feet as terra firma, but sometimes it's as stable as a house of cards. What happens when the Earth opens up to swallow homes, cars and people?

By Jacob Silverman

Folks in Montana usually expect snow or rain to fall from the sky, not ash. But the 1980 eruption of Mount St. Helens in Washington flung ash across state lines. What is this gritty, gray stuff?

By Robert Lamb

Have you ever wondered how weather stations gather all of their data? Even though technology for predicting the weather has improved, simple weather balloons do a lot of the hard work every day.

By Tristin Hopper

Let's say a big one strikes the home planet. You, however, happen to be flying above the earthquake's epicenter when the natural disaster ripples through. Would you feel it?

By Robert Lamb

Smokejumpers are the men and women who specialize in fighting blazes their ground-bound peers can't reach. So who are they, and what's the "Mutilator"?

By Jessika Toothman

Whether you're planning an outdoor wedding or a Saturday morning tag sale, it's nice to know ahead of time what the sky is going to do. But does checking the 10-day forecast do any more good than praying for sunshine?

By Robert Lamb

Before barometers and thermometers, people looked to the land and local lore to predict rain or shine. Have sophisticated statistical models and measuring tools changed the art of forecasting the weather that much?

By Robert Lamb

We've all probably looked up and wondered why the sky is blue instead of, say, brown. The sky is blue because of the way Earth's atmosphere scatters light from the sun.

By Nicholas Gerbis

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

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

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

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 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

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