Friday, March 13, 2009

A little extra- What is used to measure wind?



How do you measure winds?

A wind vane measures wind direction. An anemometer, which is to the left, measures wind speed. An aerovane measures both wind speed and direction. A radiosonde is a weather ballon that measures everything.

Thursday, March 12, 2009

Winds Aren't So Sweet


Wind can become extremely dangerous if you aren't prepared. For example Tornadoes and thunderstorms. Thunderstorms reach up to raging winds at 100 mph, but if you think thats bad tornadoes are worse. They can reach up to 250 mph or more. Tornadoes can be a mile long and up to 50 feet wide. Although tornadoes usually seem to be much more dangerous,thunderstorms cause much more damage and occur more frequently.

- So, how do we make sure we're safe?
We can start out with these guidlines from FEMA.gov :

1) Don't make your property a weapon against you.
If you have a garbage can, a grill, a shed, or things of this sort winds can pick them up and destroy other propety of yours or hurt you. Make sure anything that is outside is securely bolted, chained, or secure from high speed winds.

2) Trees
You should make sure trees on your property are no taller when full gorwn than the height of your home. This will help prevent trees hitting and damaging your home. Continue on to the bottom link to find more information on safety guidelines.


Details from:
http://www.fema.gov/news/newsrelease.fema?id=43741


More Sites: http://www.lacoa.org/PDF/ESP%2008/Nov.pdf

Winds aren't so sweet


Wind can reach high speeds and height within a few hours or even minutes. In tornadoes, for example, winds reach up to 250 mph or higher. Tornadoes can be one mile long and fifty miles wide. Tornadoes are one of the worst types of wind and can cause many deaths. Thunderstorms, which often occur before tornadoes, can reach winds up to 100 mph. Although tornadoes are much more dangerous, thunderstorms occur more frequently and cause more damage.
















Details from:


www.weathersafety.ohio.gov/TornadoDangersOfOverpasses2007.aspx - 13k

5 Most Common Wind Types in North America

There are many types of wind, beleive it or not because of the earths rotation.
- One type of wind in Canada is Barber. The wind is actually called 'Barber' because it, oddly enough, freezes everything it touches including hair. This is a very cold and moist storm.
- One other common wind is in Southwest US. It is called 'Haboob' it occurs from May to September. It is a dust storm that travels up to 50 miles per hour and can reach up to 3000 feet high. These storms can last up to three hours and are caused by thunderstorms.
- In hawaii there is a very strong wind called Pali. It runs through Pali Pass and above Honolulu.
- The next wind type is Bayamo which is in Cuba. It blows over the Bight of Bayamo and is extremely violent.
- The Chocolatero wind blows in the Gulf of Mexico. It is a warm wind and is name after the wind it carries.
These five types are in different regions of North America.


Important Winds

1) Global Winds: This is wind that blows over the surface of the ocean and pushes the water. These winds cover large areas of the Globe at a time. Circulations cells are an example of global winds. There are three cells in the southern and northern hemispheres: polar, ferrel, and Hadley.
2) Local Winds: These winds cover small regions. There are four types: thermal circulations, monsoons, mountain and valley breezes, and Chinook wind.
3) There are three types of directional global winds:
a) Trade winds – winds meet at the equator forming the intertropical convergence zone.
b) Westerlies – Dominantly westerly winds that blow on the pole ward side.
c) Polar Easterlies – These are shallow winds from the northeast that are located at low pressure regions of the polar cell.
4) Jet Streams – this is a fast flowing air in the upper atmosphere. Winds are moving at 200 to 250 mph. It effects us in the winter if winds are stronger it dips farther south. If it is north of you, you have warmer temperatures. If it is south of you, you have colder temperatures.




Details from: http://mediatheek.thinkquest.nl/~ll118/en/development/types.list.html

What is wind anyway?

Wind is air in natural motion as that moving horizontally at any velocity along the earth's surface; It can also be defined as a storm, or a stream of air. Wind blows from areas of high to low pressure. The pressure gradient and the Corriolis effect determine which direction the winds blows. The pressure gradient is the force of air moving from high to low. It is greater if the difference in air pressure is greater. The corriolis effect is an apparent force due to the earths rotation. It causes wind in the northern hemisphere to be deflected to the right. The stronger the winds the stronger the deflection will be.