What makes the wind blow

No notes for slide. What Makes the Wind Blow 1. What makes the wind blow? What Causes Differences in Air Pressure? On what part of your body would you first feel the cold? Near your feet. This is because cold air is dense and the air molecules are sinking. Coriolis Example Global Pattern of Prevailing Surface Winds Mid-latitude cyclones around the South Pole Total views 7, On Slideshare 0.

From embeds 0. Number of embeds The best protection against a tornado is early warning. In areas where tornadoes are common, many communities have tornado warning systems. In Minnesota, for example, tall towers throughout neighborhoods sound an alarm if a tornado is near. Measuring Winds Wind is often measured in terms of wind shear. Wind shear is a difference in wind speed and direction over a set distance in the atmosphere.

Wind shear is measured both horizontally and vertically. Wind shear is measured in meters per second times kilometers of height. Under normal conditions, the winds move much faster higher in the atmosphere, creating high wind shear in high altitudes.

Wind shear is higher near the coast, for example. The amount of force that wind is generating is measured according to the Beaufort scale. The scale is named for Sir Francis Beaufort, who established a system for describing wind force in for the British Royal Navy. The Beaufort scale has 17 levels of wind force. An anemometer is a device for measuring wind speed. 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. In areas of high pressure, the gases in the air are more crowded. In low pressure zones, the gases are a little more spread out.

You might think that the warm air would lead to a higher pressure area, but actually the opposite is true. Because warm air rises, it leaves behind an area of low pressure behind it. Gases move from high-pressure areas to low-pressure areas.

And the bigger the difference between the pressures, the faster the air will move from the high to the low pressure. That rush of air is the wind we experience. 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. The jet stream responds by retreating some 1, kilometers a thousand miles northward. Now, the weather in the lower 48 U. Sure, scattered thunderstorms erupt from time to time. But there are no huge storm systems spanning 1, kilometers or more to influence day-to-day events. Ordinarily, air would flow from high pressure to low pressure.

It would move across a pressure gradient. So the driving force would be known as the pressure gradient force. But the Coriolis force is still at play. These two forces cancel out. It just meanders slowly around large pressure systems. As a result, the air ends up circling around high- or low-pressure systems without moving toward or away from them.