climate connections. weather = short term day-to-day characteristics of atmospheric conditions...
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Climate ConnectionsClimate Connections
Weather = Short termWeather = Short term
• Day-to-day characteristics of Day-to-day characteristics of atmospheric conditionsatmospheric conditions
• http://video.google.ca/videoplay?docihttp://video.google.ca/videoplay?docid=-1701258125467416750&ei=tsr9d=-1701258125467416750&ei=tsr9SImnIqGI-gGGlYSJBA&q=bad+weatheSImnIqGI-gGGlYSJBA&q=bad+weather&hl=enr&hl=en
Climate = Long term Climate = Long term
• A long-term pattern of weatherA long-term pattern of weather– This can vary because of:This can vary because of:
•LatitudeLatitude
•ElevationElevation
•Coastal regionsCoastal regions
•Wind and pressure systems move from one Wind and pressure systems move from one part of the country to another. part of the country to another.
Latitude Latitude • This map shows average This map shows average
annual temperatureannual temperature• The distance from the The distance from the
equator is a key factor in equator is a key factor in whether a region is hot or whether a region is hot or cold.cold.
• The size of a landmass is The size of a landmass is also a key element.also a key element.
• Places closer to the North Places closer to the North and South poles experience and South poles experience colder temperatures than colder temperatures than those at the equator those at the equator because the same amount because the same amount of energy is spread over a of energy is spread over a larger area larger area
Relief and ElevationRelief and Elevation
• Mountain ranges act as barriers to Mountain ranges act as barriers to the movement of air massesthe movement of air masses
• Mountains cause precipitationMountains cause precipitation
• Temperature drops as elevation Temperature drops as elevation increasesincreases– As air rises, it expands because there is As air rises, it expands because there is
less air pressure. As the air expands, it less air pressure. As the air expands, it loses heat. loses heat.
ContinentalContinental
• Areas far from oceans and large Areas far from oceans and large lakes have continental climateslakes have continental climates– The temperature range is great because The temperature range is great because
there are no large water bodies to there are no large water bodies to moderate the hot temperatures. moderate the hot temperatures.
– Therefore, it is cold in the winter, hot in Therefore, it is cold in the winter, hot in the summer.the summer.
– Continental examples: __________, Continental examples: __________, ________, _____________________, _____________
Maritime EnvironmentsMaritime Environments
• Coastal locations have maritime Coastal locations have maritime climatesclimates– Because water holds heat very well, even Because water holds heat very well, even
in the winter, the temperatures are highin the winter, the temperatures are high
• There is very little change in summer There is very little change in summer and winter temperaturesand winter temperatures– Maritime examples: __________, ________, Maritime examples: __________, ________,
__________________________
Moderating Effect of Water Moderating Effect of Water
• Oceans and lakes heat up and cool down Oceans and lakes heat up and cool down more slowly than land masses.more slowly than land masses.
• In summer, a body of water remains cooler In summer, a body of water remains cooler than the land surrounding it. than the land surrounding it.
• In winter, bodies of water retain their heat In winter, bodies of water retain their heat and are warmer than the land. and are warmer than the land.
• Therefore, maritime locations near a large Therefore, maritime locations near a large body of water have cooler summers and body of water have cooler summers and milder winters than continental locations milder winters than continental locations
Ocean CurrentsOcean Currents
• The temperature of an ocean current The temperature of an ocean current affects the temperature of air that passes affects the temperature of air that passes over it.over it.
• Compare Scotland's temperature with Compare Scotland's temperature with Whitehorse’s tempWhitehorse’s temp
• http://www.pbs.org/wgbh/nova/sciencenowhttp://www.pbs.org/wgbh/nova/sciencenow/video/3204/w02-220.html/video/3204/w02-220.html
• http://videos.howstuffworks.com/hsw/8780http://videos.howstuffworks.com/hsw/8780-time-and-temperature-forecasting-hurrica-time-and-temperature-forecasting-hurricanes-video.htmnes-video.htm
Air MassesAir Masses
• A large volume of air with the climate A large volume of air with the climate conditions of the area where it is formed conditions of the area where it is formed
• See textbook page 131 figure 12-7See textbook page 131 figure 12-7
• As the air passes over land, the As the air passes over land, the moisture is released in some form of moisture is released in some form of precipitationprecipitation
• Therefore it is wetter in a maritime Therefore it is wetter in a maritime region than a continental regionregion than a continental region
Pressure SystemsPressure Systems
• Air pressure = Weight of the airAir pressure = Weight of the air
• Differences in air pressure are created Differences in air pressure are created when the earth is heated to different when the earth is heated to different temperatures. temperatures.
• Warm air is lighter than dense cool air.Warm air is lighter than dense cool air.
• WARM AIR RISESWARM AIR RISES– As the warm air rises, it cools. When it cools it As the warm air rises, it cools. When it cools it
falls toward the earth and creates an area of falls toward the earth and creates an area of high pressure. high pressure.
Winds – Differences in air Winds – Differences in air pressure produce windspressure produce winds
1.1. Heating of the ground by the sun Heating of the ground by the sun warms the air above it and causes warms the air above it and causes the air to rise. This produces a low-the air to rise. This produces a low-pressure area. pressure area.
2.2. The air cools and sinks. This The air cools and sinks. This produces a high pressure area.produces a high pressure area.
3.3. Air pressure at ground level moves Air pressure at ground level moves from high pressure to low pressure, from high pressure to low pressure, creating winds. creating winds.
Winds – drawn graphicallyWinds – drawn graphically
PrecipitationPrecipitation
NEED TO KNOWNEED TO KNOW
• Air cools as it rises.Air cools as it rises.
• As air cools, water vapour condenses As air cools, water vapour condenses more than it evaporates.more than it evaporates.
• Air rises for 3 main reasons…Air rises for 3 main reasons…
To move across an area of high To move across an area of high elevation: elevation: Relief Relief precipitationprecipitation• Mountain barriers create relief precipitationMountain barriers create relief precipitation• As moist air rises up the windward slope of a As moist air rises up the windward slope of a
mountain range, it expands and coolsmountain range, it expands and cools• As air cools, the rate of evaporation decreases As air cools, the rate of evaporation decreases
while the rate of condensation increaseswhile the rate of condensation increases• As more water vapour condenses, the cloud drops As more water vapour condenses, the cloud drops
become larger. When they are too heavy to become larger. When they are too heavy to remain suspended, they fall to the ground as remain suspended, they fall to the ground as precipitation. precipitation.
• On the leeward slope, air contracts and becomes On the leeward slope, air contracts and becomes warmer. More evaporation occurs. warmer. More evaporation occurs.
Convectional Precipitation – Convectional Precipitation – summer time precipitation summer time precipitation
• Common in the prairie provinces, Common in the prairie provinces, Ontario, and Quebec Ontario, and Quebec – Here the air heats the land very quickly Here the air heats the land very quickly
during the long summer days.during the long summer days.– Sometimes during the late summer Sometimes during the late summer
afternoons you may see these puffy afternoons you may see these puffy clouds forming into towering clouds with clouds forming into towering clouds with dark bases.dark bases.
Convectional PrecipitationConvectional Precipitation
Cyclonic PrecipitationCyclonic Precipitation
• Air masses do not easily mix; instead, a Air masses do not easily mix; instead, a boundary or Front forms between them. boundary or Front forms between them. This front is like a battlefield in the sky. This front is like a battlefield in the sky. It is here that cyclonic precipitation It is here that cyclonic precipitation developsdevelops
• A cyclonic storm is a large, low pressure A cyclonic storm is a large, low pressure system that forms when a warm air system that forms when a warm air mass and a cold air mass collide mass and a cold air mass collide
Cyclonic PrecipitationCyclonic Precipitation
• In North America, these low pressure storm In North America, these low pressure storm systems move from west to east throughout systems move from west to east throughout the year and spread precipitation over large the year and spread precipitation over large areas.areas.
• Most of the precipitation in the Prairies, Most of the precipitation in the Prairies, Ontario, Quebec and Atlantic Canada is Ontario, Quebec and Atlantic Canada is cyclonic. cyclonic.
• The ice storm of 1998 was a large cyclonic The ice storm of 1998 was a large cyclonic storm that stalled over eastern North storm that stalled over eastern North America. America.
Today’s weather Today’s weather
• http://www.theweathernetwork.com/index.php?product=weathermaps&pagecontent=weathehttp://www.theweathernetwork.com/index.php?product=weathermaps&pagecontent=weathermaps&maptype=sysrmaps&maptype=sys