44thth Grade Earth Grade Earth ScienceScience

Weeks 1 & 2Weeks 1 & 2

Effects of Sun on EarthEffects of Sun on Earth

The sun is a star. Our solar system has only one star.

Sun close-up. Paul Fuqua. (2005). Retrieved February 14, 2006, from unitedstreaming: http://www.unitedstreaming.com/

The outer visible layer of the sun has a temperature of 6,000°C (11,000°F).

Its light and heat travels through space to the earth.

http://www.spaceflightnow.com/ news/0003/02sunwarming

The Sun is the major driving force behind weather on our planet.

Sun over water. Paul Fuqua. (2005). Retrieved February 14, 2006, from unitedstreaming: http://www.unitedstreaming.com/

When the sun heats water, the water begins to evaporate. Approximately 80% of all evaporation is from the oceans, with the remaining 20% coming from inland water and

vegetation.

http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/hyd/evap.rxml

Because Earth is tilted on its axis, it does not get direct sunlight everywhere on its surface.

http://www.math.nus.edu.sg/aslaksen/gem-projects/hm/0102-1-phase/EARTHCLIMATE.htm

The sun’s heat warms the air. Warm air rises, and cool air sinks.

http://zebu.uoregon.edu/~soper/Earth/weather.html

http://zebu.uoregon.edu/~soper/Earth/weather.html

Because the earth spins (rotates) on its axis, the paths of winds bend clockwise north of the equator.

Hurricanes spin clockwise in the northern hemisphere.

Conditions of the earth's atmosphere at a given place and time are called weather.

Some of these conditions are:•Temperature•Wind speed•Precipitation•Humidity•Cloud cover

TemperatureTemperatureThe measure of how The measure of how much heat an object much heat an object has. has.

Heat is how much Heat is how much molecules in an object molecules in an object vibrate. vibrate.

The faster the The faster the molecules vibrate, the molecules vibrate, the hotter the object is.hotter the object is.http://schoolnet.gov.mt/physics/HeatEnergy2.htm

TemperatureTemperatureIn America we use In America we use the Fahrenheit and the Fahrenheit and Celsius scales for Celsius scales for measuring measuring temperature.temperature.

CelsiusCelsius is the is the temperature scale temperature scale that is used in that is used in science.science.

Fahrenheit

CelsiusImage from Pearson Prentice Hall, Inc. (2005)

http://physics.uoregon.edu/~jimbrau/BrauImNew/Chap03/FG03mp0101.jpg

Wind SpeedWind SpeedThe speed of the wind and the direction it is coming from are important for predicting weather.

Generally, fast winds coming from the north indicate a cold front.

Anemometers measure wind speed. Wind vanes measure direction. Some anemometers can do both.

Images From:http://www.earthsciweek.org/forteachers/windvane.jpg http://www.novalynx.com/200-1005-1010.html http://www.delta-education.com/images/products/0102453.jpg

PrecipitationPrecipitation

Any form of water that Any form of water that falls from clouds is falls from clouds is precipitation:precipitation:RainRainHailHailSleetSleetSnowSnow

Precipitation, illustration. Paul Fuqua. (2005). Retrieved February 14, 2006, from unitedstreaming: http://www.unitedstreaming.com

HumidityHumidityFoggy days are very humid. There is a lot of humidity in the Houston area each summer.Humidity, definition. Paul Fuqua. (2005). Retrieved February 14, 2006, from unitedstreaming: http://www.unitedstreaming.com

Cloud CoverCloud Cover

The weather forecast usually includes the The weather forecast usually includes the cloud cover. This is the amount of the sky cloud cover. This is the amount of the sky that is covered with clouds.that is covered with clouds.

Stratocumulus clouds. Paul Fuqua. (2005). Retrieved February 14, 2006, from unitedstreaming: http://www.unitedstreaming.com

Mostly cloudy, or overcast.

The Water CycleThe Water CycleThe process that water goes through The process that water goes through

from evaporation through precipitation.from evaporation through precipitation.

Water cycle. Paul Fuqua. (2005). Retrieved February 14, 2006, from unitedstreaming: http://www.unitedstreaming.com

precipitation

evaporation

condensation

Seasonal PatternsSeasonal PatternsWhat can you conclude from this chart of Houston’s average What can you conclude from this chart of Houston’s average

temperatures and rainfall?temperatures and rainfall?

Houston Jan Feb Mar AprMa

y June July AugSep

t Oct Nov Dec

Avg High◦F 61.5 65.2 72.4 79.2 84.8 89.9 92.3 92.3 88.1 81.4 72.4 64.7

Avg Low◦F 42.9 45.5 52.7 60.7 67 72.6 74.6 74.6 71.2 61.2 52.8 45.4

Avg Raininches 3.63 3.11 2.8 3.07 5.2 6.41 4.82 4.53 5.45 4.19 4.22 3.4

Avg Wind

mph 9.2 9.2 11.5 11.5 10.4 10.4 8.1 9.2 6.9 9.2 8.1 9.2

T-stormDays 2 2 4 3 7 8 11 10 7 4 3 2

http://web2.airmail.net/danb1/climate.htm