card
362

hurricanes

OLogy Series
geology
card
362

hurricanes

OLogy Series
geology

In satellite images of Earth's atmosphere, it's easy to spot the large, spiraling clouds of hurricane. These powerful storms are fueled by warm seawater, so they form over oceans near the equator. They can become larger and stronger as they cross the tropical seas. What you can't see in a satellite picture is the hurricane's incredible power. For a storm to be a hurricane, its winds must be blowing more than 74 miles (120 km) per hour .

One of the main threats from hurricanes is storm surge. What is storm surge?

swelling seawater pushed onto a coastline by high winds

powerful winds that can destroy trees and homes

rising floodwaters from heavy precipitation

Are you right?

Correct!

Storm surge can flood coastlines and completely submerge islands. Combined with a hurricane's high winds and flooding from heavy precipitation, storm surge can devastate coastal areas.

Meteorologists use satellite images to track a hurricane's path. They also rely on information from hurricane hunters who gather information by:

flying inside a hurricane

sailing underneath a hurricane

driving alongside a hurricane

Are you right?

Correct!

Instruments on their planes collect information on wind, rain, air pressure, and temperature. Data is sent to meteorologists who use it to forecast the storm's path and intensity. They also use data collected from ground stations, ocean buoys, and weather balloons.

How is global warming contributing to an increase in hurricane frequency and strength?

higher temperatures are warming the land

higher temperatures are warming the seas

higher temperatures are causing stronger winds

Are you right?

Correct!

Hurricanes feed off the warm waters at the surface of tropical oceans. Data shows that the top layer of the ocean has been warming for over a century. Most climate models project the warming will continue.

A large tropical storm is called "hurricane," "cyclone," or "typhoon" depending on its wind speeds.

Fact
or
Fiction
?

Fiction

The name depends only on where you are. What we call a "hurricane" in the U.S. is a "cyclone" in the South Pacific and a "typhoon" in Asia.

Hurricane Katrina, which destroyed New Orleans in 2005, was the strongest hurricane on record.

Fact
or
Fiction
?

Fiction

Katrina was only a category 3 hurricane, but it was one of the most devastating in U.S. history. Most of the city sits below sea level and the levees that normally hold back the water failed.

Definition: rotating storm with winds at least 74 miles (120 km) per hour
Cause: oceans warmed by the Sun and Earth's rotation
Measurement: The Saffir-Simpson Scale is a 1 to 5 rating based on a hurricane's wind speed (1 is the weakest and 5 is the strongest)
Deadliest U.S. hurricane: On September 8, 1900, some 8,000 people were killed in Galveston, Texas.
Cool Fact: Tree rings record hundreds of years of hurricane history.

Image credits: © AMNH.