Introduction to Introduction to EcologyEcology

Chapter 52 Chapter 52

ClimateClimate

►……is the average long-term weather of is the average long-term weather of an area; varies with differing amounts an area; varies with differing amounts of solar energy received by different of solar energy received by different places on Earth.places on Earth.

►Solar energy input determines Solar energy input determines temperature, precipitation, and air and temperature, precipitation, and air and ocean circulation patterns which leads ocean circulation patterns which leads to different climates and vegetation to different climates and vegetation patterns.patterns.

Uneven HeatingUneven Heating

► Regions near Regions near equator are hot due equator are hot due to more direct sun to more direct sun rays, concentrating rays, concentrating energy in a smaller energy in a smaller area.area.

► Regions near poles Regions near poles are cold due to the are cold due to the acute angle of rays.acute angle of rays.

► Regions in between Regions in between have intermediate have intermediate temps.temps.

Seasonal ChangesSeasonal Changes

► The 23.5 degree axis The 23.5 degree axis tilt causes regions to tilt causes regions to receive more direct receive more direct rays during certain rays during certain times of the year.times of the year.

► Our winter = Our winter = northern hemisphere northern hemisphere tilted away from sun.tilted away from sun.

► Our summer = Our summer = northern hemisphere northern hemisphere tilted toward sun.tilted toward sun.

Hadley CellsHadley Cells

►……vertical convection vertical convection cells that distribute cells that distribute heat and moisture heat and moisture over earth’s surface.over earth’s surface.

►Warm moist air rises, Warm moist air rises, dropping precip. dropping precip.

► Air moves N or S, Air moves N or S, then falls as cool dry then falls as cool dry air.air.

Global air circulationGlobal air circulation► Most precip tends Most precip tends

to fall at equator to fall at equator (rainforests), (rainforests), tapering off towards tapering off towards 30 degrees latitude.30 degrees latitude.

► Dry air descends at Dry air descends at 30 degrees 30 degrees (deserts).(deserts).

► Precip falls again at Precip falls again at 60 degrees (decid. 60 degrees (decid. and conif. forests).and conif. forests).

► Dry air descends at Dry air descends at poles.poles.

Coriolis Effect and WindsCoriolis Effect and Winds

► Due to the rotation Due to the rotation of the earth, air of the earth, air masses don’t just masses don’t just move N and S.move N and S.

► Air masses (winds) in Air masses (winds) in northern hemisphere northern hemisphere are deflected to the are deflected to the right.right.

► Winds in southern Winds in southern hemisphere hemisphere deflected to the left.deflected to the left.

MicroclimatesMicroclimates

►……local climates that differ from the local climates that differ from the general climate of a region due to local general climate of a region due to local topography.topography.

►……formed by:formed by: Rain shadow effect: more arid conditions on Rain shadow effect: more arid conditions on

leeward sides of mountain ranges.leeward sides of mountain ranges. Cities: buildings block wind, absorb and emit Cities: buildings block wind, absorb and emit

heat.heat. Land breezes/Sea breezes: day to night Land breezes/Sea breezes: day to night

differences in coastal areas.differences in coastal areas. Altitude: climate colder as elevation increases.Altitude: climate colder as elevation increases.

Rain Shadow EffectRain Shadow Effect

Aquatic BiomesAquatic Biomes

►Saltwater (marine):Saltwater (marine): OceansOceans Estuaries – semi-enclosed area; saltwater Estuaries – semi-enclosed area; saltwater

mixes with freshwater.mixes with freshwater. Coastal wetlands – land areas covered Coastal wetlands – land areas covered

with water at least part-time.with water at least part-time.

►Freshwater:Freshwater: Standing (lentic) – lakes, ponds, inland Standing (lentic) – lakes, ponds, inland

wetlands.wetlands. Flowing (lotic) – stream and river systems. Flowing (lotic) – stream and river systems.

Areas of ConcernAreas of Concern

►Coral reefs:Coral reefs:►High diversity and High diversity and

productivity.productivity.►Grow slowly, Grow slowly,

disrupted easily, disrupted easily, need certain temp need certain temp and nutrients.and nutrients.

►Problems: Problems: warming trends, warming trends, destruction.destruction.

► Inland wetlands:Inland wetlands:►Marshes, Marshes,

swamps, prairie swamps, prairie potholes, potholes, floodplains.floodplains.

►Vital breeding Vital breeding grounds.grounds.

►Water Water purification.purification.

►Flood control.Flood control.

Terrestrial BiomesTerrestrial Biomes►Have characteristic climate and plant Have characteristic climate and plant

life. life. ►Here is an incomplete list of biomes:Here is an incomplete list of biomes:►Temperate ForestTemperate ForestConiferous ForestConiferous Forest

Taiga Taiga Tundra TundraTemperate Grassland Temperate Grassland Savannas SavannasChaparral/Mediterranean Scrub Chaparral/Mediterranean Scrub Desert DesertTropical Rain ForestTropical Rain Forest