Presentation on theme: "Climates of the Earth Pgs.55-69"— Presentation transcript:
1 Climates of the Earth Pgs.55-69 Chapter 3Climates of the EarthPgs.55-69
2 Section 1: Earth- Sun Relationships Weather= The condition of the atmosphere in one place during a limited period of time.Climate= Term for weather patterns that an area typically experiences over a long period of time.
3 Section 1: Earth- Sun Relationships Earth’s Tilt & RotationAxis= an Imaginary line running from the North Pole to the South Pole through the planet’s center. Currently an angle of 23 ½ *.Temperature= the measure of how hot or cold a place is. Common temperature scales: Fahrenheit (*F) or Celsius (*C).Rotates every 24 hrs, west to east, 1st one hemisphere & then the other toward the sun, alternating the light of day & the dark of night.
4 Section 1: Earth-Sun Relationships Earth’s RevolutionRevolution= 1 complete trip around the sun.Seasons are reversed North & South of the equator. Around March 21st the sun’s rays fall directly on the equator.Equinox= “equal night” daylight & nighttime hrs are equal. This day marks the beginning of spring in the northern hemisphere.
5 Section 1: Earth-Sun Relationships The Tropics of Cancer & CapricornTropic of Cancer=23 ½* N. latitude, northern most point on the Earth to receive direct rays of the sun.Summer Solstice= June 21st; making this the longest day of sunlight in the northern hemisphere & marking the 1st day of summer.Tropic of Capricorn=23 ½* S. latitude, southern most point on the Earth to receive direct rays of the sun. This equinox marks the beginning of fall in the northern hemisphere.Winter Solstice= December 22nd. Shortest day of shortest daylight, begins the winter season in the N. hemisphere.
7 Section 1: Earth-Sun Relationships 6 months a yr 1 pole is tilted toward the sun & receives continuous sunlight while the other pole is tilted away from the sun & receives little or no sunlight.North Pole= sun never sets from March 20th- September 23rd.South Pole receives continuous daylight from September 23rd – March 20th. This is a phenomenon known as the Midnight Sun.
8 Section 1: Earth-Sun Relationships The Greenhouse EffectGreenhouse Effect= the capacity of certain gasses in the atmosphere to trap heat, thereby warming Earth.Global Warming= a rise in atmospheric CO2 levels along with a general rise in global temperatures.
9 Section 2: Factors Affecting Climate Latitude & ClimateLow Latitudes: Area between the Tropics of Cancer & Capricorn. (includes the equator) receives direct sun rays all yr. Warm, hot climates, these are know as the Tropics.High Latitudes: Earth’s polar areas.Arctic Circle= latitude 66*N, continuous but indirct sunlight or twilight March 20th- September 23rd.Antarctic Circle= latitude 66*S, continuous but indirect sunlight or twilight September 23rd -March 20th.Mid-Latitudes= Between the Tropic of Cancer & the Arctic Circle & the Tropic of Capricorn & the Antarctic Circle. Temperate climates, fairly hot-fairly cold w/ dramatic seasonal changes.
11 Section 2: Factors Affecting Climate Elevation & Climate: At all latitudes elevation influences climate due to the relationship between the elevation of a place & its temperature.Wind & Ocean Currents: Air moving across Earth’s surface is wind. Rising Warm Air=Low Pressure. Falling Cool Air= High Pressure.Prevailing Winds= wind in a region that blows in a fairly constant directional pattern, determined by latitude & Earth’s movement.Coriolis Effect= an effect that causes the prevailing winds to blow diagonally rather than along strict north-south or east-west lines.
12 Section 2: Factors Affecting Climate Doldrums=At the Equator, global winds are diverted north & south leaving a narrow, generally frequently windless area near the Equator.Currents= cold or warm stream of seawater that flows in the oceans, generally in a circular pattern. Coriolis Effect is present here as well, causing the currents to move in a clock-wise motion in the N. Hemisphere & counter-clock-wise in the S. Hemisphere.El Nino= periodic change in the pattern of ocean currents & water temperatures in the Mid-Pacific region.
13 Section 2: Factors Affecting Climate Windward= the side of the mountain range facing the wind.Leeward= facing away from the direction from which the wind is blowing.Rain Shadow= dry area of land found on the leeward side of a mountain range.
14 Section 3: World Climate Patterns Natural Vegetation= The plant life that grows in an area where the natural environment is unchanged by human activity.The Tropics= hot & wet weather all yr. Avg. temp. 80* F. avg. rainfall 80 inches a yr!Dry Climates: Desert & SteppeDesert: sparse plant life, avg. rainfall less than 10 inches a yr. occur in less than 1/3 of Earth’s total land area. The Sahara extends over 1/3 of Africa.Oasis= area of lush vegetation.Steppe= treeless grasslands avg. rainfall: in.
16 Section 3: World Climate Patterns Mid-Latitudes: variable weather patterns & seasonal changes.Coniferous =Trees that have cones and needle-shaped leaves, keep their foliage year round.Deciduous= Trees that have broad leaves that change color & drop in the fall.Mixed forests= both kinds of trees.Costal latitudes are known as Mediterranean Climates; mild rainy winters, hot & sunny summers. Vegetation includes Chaparrals, thickets of woody bushes & short trees.
17 Section 3: World Climate Patterns High latitudes: freezing temperatures all year due to lack of sunlight.Subarctic Climate Region: bitterly cold winters, short cold winters.Permafrost= permanently frozen subsoil.Tundra: bitter cold for 6 months, located in N. Hemisphere. Low bushes, short grasses, & lichens.Highland Climates: The higher the elevation the colder the climate.Climate changes: human interaction. Burning of fossil fuels releases gases that fall in rain & snow.Smog= visible chemical haze