This is because the air gets funneled into a smaller and smaller path. As it does so, its flow rate increases. In the Northern Hemisphere, this makes the air flow to the right with increasing speed. This swirling action is known as the Coriolis force. This affects everything. A football tossed from one end of a stadium to another will naturally deflect 1. Closer to the mid-latitudes, they howl. This is how the jet stream forms. This current of air snakes around the planet at speeds greater than kilometers miles per hour.
The more rapidly it moves, the more the northern jet stream curves east. But as the air moves poleward, it never actually gets to the poles. As a result, the jet stream meanders as it circles the Earth in each hemisphere. In the North, it moves air west to east in a circle around the mid-latitudes and the opposite in the Southern Hemisphere , changing its path from season to season.
Poleward of the jet stream, the atmosphere is turbulent. Along this temperature boundary, a fierce atmospheric battleground develops. Colliding air masses of different temperatures spin up cyclones and other severe weather. The position of the jet stream influences the type of weather a region encounters. Consider the Northern Hemisphere, for instance. This allows an extensive dome of super-cold air to bank up nearby. Atmospheric scientists refer to this flowing pool of cold air and low pressure as the polar vortex.
It swells in size during winter. And when this flow of cold air surges southward, it pushes the jet stream into southern Canada and the northern United States. That can bring seemingly endless snowstorms to the upper Midwest and Northeast during the dead of winter. In summer, the poles warm. This weakens the temperature gradient between these zones and the equator.
Anemometers are used with tornado data collectors, which measure the velocity , precipitation, and pressure of tornadoes. The scale has six categories that designate increasing damage. In , the Enhanced Fujita Scale was established in the U.
The Enhanced Fujita Scale has 28 categories, with the strongest cataloging damage to hardwood and softwood trees. Hurricanes are measured using the Saffir-Simpson scale. In addition to tropical depressions and tropical storms, there are five categories of hurricanes. The most powerful, Category 5, is measured by winds whipping at kph mph. Impact on Climate Wind is a major factor in determining weather and climate. Wind carries heat, moisture, pollutants, and pollen to new areas.
Many daily weather patterns depend on wind. A coastal region, for instance, undergoes changes in wind direction daily. The sun heats the land more quickly than the water.
Warm air above the land rises, and cooler air above the water moves in over the land, creating an inland breeze. Coastal communities are usually much cooler than their inland neighbors. Rain shadow s are created as wind interacts with a mountain range. As wind approaches a mountain, it brings moisture with it, which condense s as rain and other precipitation before coming over the crest of the mountain. Winds also help drive ocean surface currents around the world.
The Antarctic Circumpolar Current transports cold, nutrient-rich water around Antarctica. Due to the Gulf Stream, Northern Europe enjoys a much warmer, milder climate than other areas at similar latitudes, such as the U.
Impact on Ecology Wind has the power to move particles of earth—usually dust or sand—in great quantities, and over far distances. Dust from the Sahara crosses the Atlantic to create hazy sunsets in the Caribbean. Winds transport volcanic ash and debris for thousands of kilometers.
The massive eruption of Krakatoa, an island volcano in Indonesia, had even more dramatic atmospheric results. Winds carried volcanic ash and debris high in the atmosphere across the globe. Europe endured years of cold, damp summers and pink sunsets. In some cases, this takes places in the desert, as sand dune s migrate and change shape over time. The Altiplano region of South America has dramatically shaped ventifact s—rocks carved by the wind-driven sand and ice.
Loess , a sediment that can develop into one of the richest soils for farming, is easily swept up by wind. Even when farmers take precautions to protect it, the wind can erode up to 2. The most famous example of this devastating windstorm is probably the Dust Bowl of s North America. Dust Bowl storms could reduce visibility to a few feet, and earned names like "Black Blizzards. However devastating to the economy, wind is an important way plants disperse seed s.
This form of seed dispersal is called anemochory. Plants that rely on anemochory produce hundreds and even thousands of seeds. Some of the most familiar seeds dispersed by the wind are those of the fuzzy dandelion. Wind Energy Wind has been used as a source of energy for more than a thousand years—it has pushed ships around the globe and been captured in windmill s to pump water; it has turned giant stones to grind grains, make paper, saw logs, and crush ore. Today, most wind energy is used to generate electricity for homes, businesses, hospitals, schools, and industry.
Wind is a renewable resource that does not directly cause pollution. Wind energy is harnessed through powerful turbine s. Wind turbines have a tall tubular tower with two or three propeller-like blades rotating at the top. When the wind turns the blades, the blades turn a generator and create electricity. Often, wind turbines are collected in windy areas in arrays known as wind farm s.
Many wind farms have been established on mountains, in valleys, and offshore, as the air from the ocean interacts with land-air. Some people think wind turbines are ugly and complain about the noise they make. The slowly rotating blades can also kill birds and bats—but not nearly as many as cars, power lines, and high-rise buildings. The economic drawback to wind farms, however, is the wind itself. If it's not blowing, there's no electricity generated. Still, use of wind energy has more than quadrupled between and Germany has the most installed wind energy capacity, followed by Spain, the United States, India, and Denmark.
Development is also growing quickly in France and China. Kamikaze Like the Protestant Wind, kamikaze were specific historical winds. Kamikazetranslated as divine windswere major typhoons that destroyed the invading Mongolian Navy off the coast of Japan in the late s.
In the 20th century, kamikaze became the informal name for suicide attacks during World War II. The official name for kamikaze strategy is tokktai. Protestant Wind The Protestant Wind refers to the lucky weather encountered by the British Navy of the 16thth centuries. Britain had just become a Protestant nation. Anemoi Deities representing the winds play an important role in mythologies around the world. In Europe, ancient Greek myths refer to the Anemoi , or wind gods, as Boreas north wind , Eurus east wind , Notus south wind , and Zephyrus west wind.
In Aztec mythology, the four wind gods were Mictlanpachecatl north wind , Tlalocayotl east wind , Vitztlampaehecatl south wind , and Cihuatecayotl west wind.
Many people were confined to their homes for a week. The devastation and inconvenience led urban leaders to invest in the creation of the first subway system in the U. Age of Sail The ability of ships to sail with powerful trade winds helped determine the political and engineering history of the Age of Exploration, sometimes nicknamed the Age of Sail.
Spanish, Portuguese, and British ships were quick, relatively easy to maneuver, and their large, complex series of sails exploited trade winds and southern westerlies to travel across the ocean.
Chicago is a lakeside city that experiences cool breezes coming off Lake Michigan. It is not, however, any windier than most other cities. The nickname most likely came from Chicagos relationship with Cincinnati, Ohio, in the 19th century.
Their industrial economies, as well as their baseball teams, were fiercely competitive. Cincinnati leaders dismissed Chicago baseball players and businesses as being insubstantial and meaninglesswindy and full of hot air. Extraterrestrial Winds The same forces that cause winds on Earthuneven heating by the sun and the planets rotationcause other planets to develop strong winds. Jupiters famous Great Red Spot is actually a centuries-old hurricane-like storm, swirling at around kph mph.
The strongest winds in the solar system, however, belong to its outermost planet, Neptune. Neptunian winds whip at speeds up to 2, kph 1, mph. Extrasolar planets those outside our solar system have even faster winds. The extrasolar planets of 51 Pegasi have winds that blow 14, kph 9, mph! Gone with the Loo There are dozens of names for winds that blow through specific regions.
Some, like the noreasters that blow from the northeast down the East Coast, are not creatively named. Here are some others: barber : cold, moisture-laden wind that freezes on contact with hair and beards. Coromuel : strong, warm wind that blows from afternoon to early morning through La Paz, Baja California, Mexico. The wind was named after British sailor Samuel Cromwell, whose name the locals could not pronounce. Hawk : strong, cool breeze blowing westward through Chicago from Lake Michigan.
The Levant, the Mideast region in the eastern Mediterranean, does not experience the levant. Loo : strong, hot summer wind that blows across northern India from the arid deserts to the west, and is only stopped by the arrival of the monsoon. The Loo is such a powerful ecological and cultural force that ice creams and sherbets are consumed to combat Loo-induced fatigue.
November witch : hurricane-force winds that develop as cold Arctic air masses meet warm air from the Gulf over the Great Lakes. Pembrokeshire Dangler : area where prevailing winds converge and cause a line of cold rain and snow to dangle north-south across the Irish Sea.
Santa Anas : hot, dry winds that blow from the deserts and mountains of inland California to the coast. Santa Anas are often responsible for spreading Southern Californias destructive wildfires, earning them the nickname murder winds. Siroccos carry tons of dust and sand throughout northern Africa, and contribute to wet weather as they reach Europe. Also called the West Wind Drift. The Coriolis effect makes storms swirl clockwise in the Southern hemisphere and counterclockwise in the Northern Hemisphere.
The gases that make up our atmosphere do interesting things as the temperatures change. When gases warm up, the atoms and molecules move faster, spread out, and rise.
When air is colder, the gases get slower and closer together. Colder air sinks. The sun warms up the air, but it does so unevenly. Because the sun hits different parts of the Earth at different angles, and because Earth has oceans, mountains, and other features, some places are warmer than others.
Because of this, we get pockets of warm air and cold air. The polar easterlies form when the atmosphere over the poles cools. This cool air then sinks and spreads over the surface.
As the air flows away from the poles, it is turned to the west by the Coriolis effect. Again, because these winds begin in the east, they are called easterlies.
What is a sea breeze? On a warm summer day along the coast, this differential heating of land and sea leads to the development of local winds called sea breezes. As air above the land surface is heated by radiation from the Sun, it expands and begins to rise, being lighter than the surrounding air. To replace the rising air, cooler air is drawn in from above the surface of the sea.
This is the sea breeze, and can offer a pleasant cooling influence on hot summer afternoons. What is a land breeze?
A land breeze occurs at night when the land cools faster than the sea. In this case, it is air above the warmer surface water that is heated and rises, pulling in air from the cooler land surface.
How is wind helpful to Earth? Wind is the fastest growing source of electricity in the world. It's often one of the least expensive forms of renewable power available. Some experts say it can sometimes be the cheapest form of any kind of power.
Generating power from the wind leaves no dangerous waste products behind. Best of all, its supply is unlimited. How do windmills work? Windmills work because they slow down the speed of the wind. The wind flows over the airfoil shaped blades causing lift, like the effect on airplane wings, causing them to turn. The blades are connected to a drive shaft that turns an electric generator to produce electricity. What are some different types of wind names? Many local wind systems have their own names.
Here's a few! The scale was created by the British naval commander Sir Francis Beaufort around Beaufort number. Wind motion visible in smoke.
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