Weather and Climate Part 1 - Introduction CGF3M Crescent School

Definitions Weather: all the atmospheric activities that occur at a given place at a given time. The condition of the atmosphere. Climate: atmospheric conditions a place has, averaged over a long period of time. The average of weather. Include: temperature, wind speed and direction, humidity, precipitation, pressure, cloud cover.

Weather: Short Term Small Scale Difficult to predict and forecast (Daily) Temperature, Precipitation, Humidity, Wind direction and speed, pressure Meteorology Climate: Long Term Large Scale Easy to predict (Seasonal) Climate is the averages of Temperature, Precipitation etc. Climatology

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Climatic Controls It is obvious that not all places on earth experience the same weather or climate. There are a number of factors that effect the weather or climate. They are called ‘Climatic Controls’. Remember Grade 9 and LOWER - Near Water! This year we will change it up a bit.

There are Four basic variables that influence climate: 1.Insolation: amount of solar radiation a place receives (amount of daylight & angle of suns rays - Latitude) 2.Elevation: Altitude (air pressure/heat released) 3.Proximity of water bodies: (moderates, continental areas with large lakes) 4.Ocean currents: movement of heat from the equator toward the poles (temperature & precipitation)

Microclimates Subtle variations in temperature, humidity and precipitation on a small scale. –Exposure: influence of wind on temperature and humidity –Albedo: surfaces convert solar energy into heat Walk (outside) around the school one day and you will notice surprisingly different conditions around the area that contains the school

Dark Pavement Natural cover - grass, trees etc. Strong Sun The Shade Buildings acting as barriers to the sun or wind

Exposure: Slopes - southern slopes receive more sun than northern slopes Wind Chill - how cold the temperature feels to people because of the wind. A surface that is heated by the sun will be cooled quickly if there is a strong wind that blows the heated air away quickly. This type of surface will also dry faster.

Albedo: Dark surfaces convert more of the available heat than light surfaces. Walk across black pavement with bare feet on a hot summer day, then walk on grass. Objects with low albedo are cooler than objects with high albedo

Urban Heat Island: Concrete Tall buildings - wind tunnels Cars, air conditioners Subways Pollutions - Inversions Increased levels of Carbon Dioxide, Carbon Monoxide, Nitrous oxide etc. Many cities that have large parks and ravines compensate this Urban Heat Island effect.

The End Go to Part 2 of the Weather and Climate slide shows