CHAPTER 2 SECTION 1Weather and Climate

Weather and Climate

Weather- the condition of the bottom layer of the earth’s atmosphere in one place over a short period of time- descriptions of weather include: temperature, moisture/precipitation, wind- example: cold, snowy, windy- almost in constant state of change- may influence other areas/regions

Weather and Climate

Climate- weather patterns that an area typically experiences over a long period of time- factors of climate: elevation, latitude, location to landforms/water

The Sun and the Earth

The Sun- the ultimate source of the earth’s climate and of life on earth

The Sun and the Earth

The Greenhouse Effect- solar radiation

- small amount reaches earth’s atmosphere

- some reflected back to space- some remains to warm earth’s land

and water*atmosphere prevents heat from escaping back into space too quickly

The Sun and the Earth

Rotation - rotation- the spinning motion of the earth as it travels through space

- axis- invisible line through the center of the earth from pole to pole (23 ½ tilt)

- one rotation completed in 24hrs.

- Earth spins from west to east

The Sun and the Earth

Revolution- orbit- the earth moves around the sun in a nearly circular path- revolution- one complete orbit around the sun

- one revolution completed every 365 ¼ days- length of a year

- Tropic of Cancer (23 ½ N) and the Tropic of Capricorn (23 ½ S) receive the most direct sunlight

The Sun and the Earth

Solstices- June 21 and December 21- the days when the sun appears directly overhead at the Tropics of Capricorn and Cancer

Equinoxes- March 21 and September 23- the lengths of day and night are nearly equal everywhere on the earth

The Sun and the Earthpage 65

Latitude and Climate- The sun’s rays always fall most directly at or near the Equator- the rays grow less direct as they fall closer to the poles

Tropical Zones Temperate Zones Polar Zones

Other Influences on Climate

Nearby Bodies of Water- large bodies of water affect the surrounding climates- winds that blow over water take on the water’s temperature- milder climates

Elevation

Nearby Landforms

World Climate Regionspage 72

Climate Regions- tropical- dry- moderate- continental- polar/highlands

Changing Climatespage 73

Global warming