chapter 6. weather and climate weather refers to the day to day conditions of the atmosphere in a...
TRANSCRIPT
Weather and ClimateWeather refers to the day to day conditions
of the atmosphere in a specific areaClimate describes the weather conditions
that occur in a specific area over a long period of time.
Meteorologist is a weather specialistHumidity refers to the amount of moisture
in the air and is measured as a percentagePrecipitation is all the moisture that falls
from the sky
Weather and Its Influences
Weather affects our lives dailySometimes the conditions can be extreme
and cause natural disastersImpact of weather is not always dramaticPlants and animals are also influenced by the
conditions of the atmosphere
Humidex used to measure the combined effect of temperature and humidity
Wind Chill factor measures the chilling effect on human skin of the wind combined with cold temperatures
Ultraviolet (UV) rays can damage the eyes and burn deeply into unprotected skin
Health Indicators
Weather Patterns across Canada
Geographers search for patterns so that they can predict changes to the Earth’s surface
Identifying weather patterns make it easier to predict tomorrow’s weather
Weather patterns follow a general pattern
Weather Patterns across Canada (cont.)In Canada, places near Atlantic and Pacific
Oceanare wetterPrince Rupert, BC is the wettest, receives
precipitation for over 300 days a yearWinter weather is milderWest Coast temperatures rarely drop below
freezing
Weather Patterns across Canada (cont.)Interior of Canada and far North
Enjoy more hours of sunshineReceive less precipitationReal extreme in temperaturesHot summers and cold winters
How Air Masses Affect the WeatherAir masses are large bodies of air with
particular temperature and moisture characteristics
Warm front is when warm, moist air from the Gulf of Mexico moves north
Cold front is when cold, dry air from the Arctic moves southward
How Air Masses Affect the Weather (cont.)Communities near the Great Lakes have
changeable weatherDifferent types of air masses push into
regions from different directionsWarm front rides up over cooler air in front of
it causing clouds to form and is often followed by precipitation
Cold front pushes warm moist air upward and causes dark clouds to form and is often followed by powerful thunder and lightening storm.
Canada’s “Storm of the Century”Early 1998Eastern Ontario and Southern Quebec5 continuous days of freezing rainLarge warm air mass from Gulf of Mexico
swept northeastward by a high speed wind (jet stream)
In southern Canada, it met a cold air mass and rode up over it
Clouds and rain developed, and the water droplets froze wherever they landed
Canada’s “Storm of the Century”Weight of ice caused trees and hydro towers
to breakOver 2 million people left without power in
the middle of winter25 deathsAt least half a billion dollars damageWidespread environmental destruction
How the Oceans affect the WeatherEl Nino
Spanish for “boy child” Warm Pacific Ocean current that reaches the coast
of Peru during December Sometimes the water is warmer than usual and
causes great changes in weather over North and South America
Warm ocean water evaporates more quickly and results in more clouds and precipitation
During El Nino winters Canada has milder conditions and rain often replaces snow