Winds

1. Winds Created by: Peter D. Joe G. Matt B. Chaz M.

2. Dust Storms -Dust storms form when particles of dirt are loosely bound to the surface. Grains of sand lofted into the air by the wild fall back to the ground within a few hours, but smaller particles remain suspended in the air for a week or more and can be swept thousands of kilometers downwind. -Between June and August, the deserts surrounding the Arabian Sea are the dominant source of dust aerosols, which are carried to the northeast towards India and Asia by the Indian monsoon winds. -Dust storms are common in dry windy places, such as deserts. They are least likely to occur in northern, forested areas. -They are never here in Ontario because of not enough flat dry sandy land-There have not been any recent dust storms in our area. -Dust storms cannot cause damage by destroying buildings but can cause harm to your lungs by dust and soil. -They can take place between June and August. -The weather factors that interact to produce dust storms are: wind, dust particles, and sand. -Approximately half of the dust in today’s atmosphere may be the result of changes to the environment caused by human activity, including agriculture, overgrazing and the cutting down of forests.

3. Chinook Winds - The Chinook Winds are caused by moist weather coming from the Pacific coast, cooling as they climb the western slopes, and then rapidly warming as they drop down the eastern side of the mountains. - The Chinook Winds occur from November to April or May. - They are most common in Alberta. They would least likely occur in places without mountains, like Saskatchewan. - Chinook Winds have not been in our area. - The Chinook Winds come in Alberta every year, so there have been recent occurrences - They can reach high speeds and can break trees, and also melt snow, which interrupted the Olympics in Alberta. - The Chinook winds come once every year, for 20 to 30 days. - Condensation Level, Cooling air, Warming Dry Air, Warm Front, Rain, and Snow are all factors of weather that effect the Chinook Winds. Exciting Details or Facts -  The Chinook winds are between 25 and 50 miles per hour, and can reach tree bending and breaking speeds of 100 miles per hour.

4. Sirocco • Sirocco forms as a result of surface and upper level depressions moving eastward across the southern Mediterranean Sea or North Africa. The air flows northward from the Sahara desert, south of Tunisia, as well as from Libya and Egypt, producing hot, dry and dusty conditions over the northern African coast, resulting in poor visibility and damage to instruments and equipment. • It may blow at any time of the year. It blows mainly from March to June in northern Adriatic and it blows from autumn until the end of winter in the southern Adriatic. • It occurs in the northern Mediterranean Sea and the Adriatic Sea. • These winds are unlikely to occur in our area because it originates from the hot, dry air masses over Libya and Egypt. • The Sirocco winds are highly unpredictable. They can occasionally bring with them extremely high temperatures that can cause heatstroke, exhaustion and forest fires. • A good example of this occurred in early July 1998 in the countries around the Mediterranean. • The Factors of Weather that take place to produce Sirocco winds are a result of surface and upper level depressions moving eastward across the southern Mediterranean Sea or north Africa • The Sirocco is a warm, humid wind blowing from the east-southeast to the south-southeast that blows with a constant force, of usually about 15-20knots.

5. Katabatic • -They are formed when air in high pressure systems sits over an elevated, snow covered plateau. The air over the snow cools down by convection, creating a shallow dome of cold air. The high density of the cold air causes it to begin to descend from the highlands, into the valley. The landscape can channel and force the airflow to converge, causing it to strengthen. The winds are driven down the slopes by gravity. • -They can occur at any time of the year, but they require winter like conditions. • -They are common in cold areas with mountains, plateaus, and hills. They are unlikely to occur in flat areas, but they occur almost anywhere in the world. • -They cannot occur in our area because Essex county has a flat topography. • -They are occurring all the time, around the world. • -Katabatic winds with their freezing temperatures can occasionally have speeds up to 20m per second which could easily cause serious damage. • -High pressure systems, convection, and gravity interact to create katabatic winds

6. Mistral • -         The Mistral Winds is a cold, northerly katabatic wind flowing into the Gulf of Lion from the Southern Coast of France. • -         Mistrals are most common during the winter and Spring. • -         Mistrals often develop when cyclogenisis occurs over the Gulf of Genoa • -         Mistral winds are also considered the most dangerous of all Mediterranean winds because of there high speed and persistence. • Interesting Facts • - In the winter, wind speeds can reach over 100 knots offthe south coast of France.