Weather, Climate, & Seasons

http://youtu.be/zz_CRzcIT-Q

layer of gases that surrounds the Earth composition: 78% nitrogen, 21% oxygen

Troposphere Lowest layer of the atmosphere From sea level up to ~ 10 mi. Where weather occurs

Stratosphere From ~ 10-30 mi. out Where ozone layer is (filter for UV light)

Mesosphere Thermosphere

Weather - condition of the atmosphere at any one time. Ex. Rainy, hot, dry, cold, etc.

Climate – average weather conditions over a long period of time. Ex. Arid, temperate, tropical, etc.

Latitude zones (sunshine) Elevation Wind (direction and speed) Topographic barriers Ocean currents Precipitation Temperature Cloud coverage

Because of earth’s tilt, different areas receive different amounts of sun.

Low (Tropical)

Low (Tropical)

Mid (Temperate)

Mid (Temperate)

High (Polar)

High (Polar)

0˚ Equator

23.5˚S Tropic of Capricorn

23.5˚N Tropic of Cancer

66.5˚S Antarctic Circle

66.5˚N Arctic Circle

Tropical – hot and humid year-round, little seasonal changes, two seasons are wet & dry, little changes in daylight hours, average temps range between 72-90˚

Temperate – (moderate); has 4 distinct seasons each clearly marked by changes, temps are not extreme, but vary greatly by season, rainfall is moderate

Polar – characterized by extremely cold temps. in long winter seasons, very short summers with mild temps, during summer long hours of daylight, during winter very few hours of daylight

Refers to height at or above sea level

As you go up in elevation (mountains and high plateaus), the temperature drops

Known as vertical or highland climates

High elevation + high latitude = coldest climates

Low elevation + low latitude = warmest climates

Air movements caused by the sun heating Earth’s surface unevenly

Distribute heat and moisture around the world

Have global and seasonal patterns Ex. Monsoons

Movement of ocean water by forces such as wind and tides

Occur at the surface as well as deep under water; vary in temperature

Cause temperatures of nearby land to be more uniform and moderate

Seasonal change in the direction of prevailing winds, often bringing heavy rains. Affects mostly country of India, but also other SE Asian countries

Orographic (rain shadow) effect – the contrast in precipitation caused by a change in elevation, primarily due to mountains.

Windward side - gets the moisture, more abundant vegetation

Leeward side - faces away from the moisture and is dry, creates a rain shadow desert

Notable rain shadow deserts: Death Valley in California Eastern Costa Rica Hispaniola (Haiti & Dominican Republic) NW of Himalaya Mts.

Draw the following diagram in your notes.

Add: - cloud with precip.- vegetation- weather characteristics

Tropical storms that develop near the equator due to the very rapid evaporation of warm ocean waters Happen in the late summer months Winds of at least 74 mph Hurricanes in the Atlantic, typhoons in the

Pacific

Warm ocean current that starts in the Gulf of Mexico and travels along the east coast of the U.S.

Crosses North Atlantic Ocean and brings warm water to the British Isles & Norway, making them warmer than they normally would be

Also drives tropical storms and hurricanes to Gulf and east coasts of U.S.

ENSO – El Niño Southern Oscillation

A weather phenomenon in which rising temperatures of the Pacific Ocean brings heavier than usual rains to the Eastern Pacific

Causes extreme drought in the Western Pacific

Disrupts marine life as well

Normal Conditions

El Niño Conditions

Earth tilts at a 23.5˚ angle, perpendicular to the eclipticEcliptic – plane on which Earth orbits around the Sun

Rotation - one complete spin of the Earth on its axis - takes 24 hours.

Revolution - one complete orbit of earth around the sun - takes 365.25 days (leap year).

Spring, summer, autumn, winter caused by the tilt and revolution of the

Earth Duration of each season varies

according to latitude zones Seasons are opposite in the Northern

and Southern Hemispheres.

Are the first days of every season Solstice - longest or shortest day of the year

June 21 – summer solstice Dec. 22 – winter solstice

*for Northern Hem Equinox – equal day night

March 21 – Vernal equinox Sept. 22 – Autumnal equinox

*for Northern Hem Opposite for Southern Hemisphere

DATE_____ (solstice/equinox)

Northern Hemisphere Season

Southern Hemisphere Season

March 21

June 21

Sept. 22

Dec. 22

Draw this chart on your notes and fill it in.