Seasons of Change

equinox

Either of two times of the year when the sun crosses the plane of the earth's equator and day and night are of equal length

Albedo

Ability of a surface to reflect light (the reflectivity of a surface).

Summer Solstice

On June 21, it is the longest day in the Northern Hemisphere due to the fact that the sun is directly over the tropic of Cancer

Vernal Equinox

On March 21-22, it is when there is an equal number of hours of day and night due to the fact that the sun is directly over the equator., Occurs in March and marks the beginning of spring in the Northern hemisphere

Autumnal Equinox

The equinox that occurs on September 22 or 23 in the Northern Hemisphere and on March 21 or 22 in the Southern Hemisphere

Winter Solstice

The solstice that occurs on December 21 or 22 in the Northern Hemisphere and on June 21 or 22 in the Southern Hemisphere (tropic of Capricorn)

Differential Heating

Unequal heating that occurs across earth's surface and when combined with the earth's rotation becomes the engine that drives earth's weather.

Equator

an imaginary line around the Earth forming the great circle that is equidistant from the north and south poles

When do the solstices and equinoxes occur?

b. Summer solstice- june 21/22 b. winter solstice- december 21/22 a. vernal equinox- march 20/21 d. autumnal equinox- september 22/23

diurnal

daily

solstice

either of the two times of the year when the sun is at its greatest distance from the celestial equator

How does the tilt of the Earth's axis affect the intensity of the sun's rays?

if the northern hemisphere is pointed toward the sun, the rays will be direct if it is tilted away from the sun, the rays will be indirect

Insolation

incoming solar radiation

indirect rays

light rays that do not hit the Earth straight on

How are the seasons in the Northern and Southern hemispheres related to each other?

opposite seasons

direct rays

rays or sunlight (insolation) that strike EArth at an angle 90 degrees, also called vertical rays

Where do the sun's rays fall on the solstices and equinoxes?

solstices- tropics equinoxes- equator

zenith

the point above the observer that is directly opposite the nadir on the imaginary sphere against which celestial bodies appear to be projected

What are the seasons like at the poles?

24 hours of daylight or 0 hours on solstices 12 hours everywhere in the world on equinoxes

Tropic of Cancer

A line of latitude located at 23°30' north of the equator. The Sun is directly overhead the Tropic of Cancer on the summer solstice in the Northern Hemisphere (June 20 or 21). It marks the northernmost point of the tropics, which falls between the Tropic of Cancer and the Tropic of Capricorn.

Tropic of Capricorn

A line of latitude located at 23°30' south. The Sun is directly overhead the Tropic of Capricorn on the summer solstice in the Southern Hemisphere (Dec. 20 or 21). It marks the southernmost point of the tropics.

What are 2 reasons for seasons?

1. Tilt of Earth 2. Revolution around the sun