The Sun’s Effect on Weather

Contents The Sun’s Key Roles The Sun’s Key Roles n Effects on Earth’s weather n Moving Air: The Wind n Evaporation n Hurricanes

What is the Sun?? n The Sun is a star, the closest star to planet earth. n It is the largest object in the solar system, contains 99.8% of the total mass. n It is estimated to be about 4.5 billion years old / Let’s take a look!!

The Sun’s Key Roles n The sun supplies light and heat to our solar system. n The sun is the Earth’s major source of heat energy. n The Sun’s heat sustains life and controls our climate.

The Sun’s Key Roles n The Sun keep the temperature of most of the Earth’s surface at 51 to 49 degrees Celsius. –Most living things can only survive at 0 to 49 degrees Celsius. n Did You Know: If the amount of sunlight reaching the Earth was cut by 1/10th, the oceans would turn to ice and life on Earth would cease to exist.

Sun’s Effect on Weather n The Sun is a major contributor to the world’s weather. n The Sun’s heat warms the Earth’s land and water surfaces. n The Earth absorbs the heat and releases it into the atmosphere, which heats the air above, and causes moving air. n The movement of air causes winds which lead to weather changes.

Sun’s Effect on Weather

The Wind n The absorption and release of heat energy into the atmosphere results in moving air, also known as Wind. n The air moves, because the surface is unevenly heated. (some surfaces absorb heat faster than others) n With movement, the air pressure (weight of air pressing on everything around it) changes, these changes affect weather.

The Wind: Sea Breeze n n On a Beach: When land heats up faster than water, air above land becomes warmer than air above water. n n The warm land air rises, and is replaced by cool moving air from above the water. n n This is known as a breeze (or Sea Breeze) n n This type of air movement can happen anywhere where the surfaces are unevenly heated.

The Wind: Sea Breeze

Evaporation n One factor that affects air and weather is water vapor. –Creates Air Moisture n Evaporation is the process of changing liquid to gas. When Earth’s liquid water (oceans etc…) evaporates, it releases gas called water vapor. n Heat from the Sun speeds up evaporation

Evaporation n The water vapors are held in the atmosphere, as air cools, the vapors become condensation (tiny droplets of water that form clouds) n When the droplets grow larger and get too heavy, they fall back to Earth as precipitation: – rain, snow, hail, or sleet.

Evaporation n Water vapors in the air causes humidity. n Humidity and temperature combined causes moving air masses, which results in weather front. –Cold Front – moving mass of cool air –Warm Front – moving mass of warm air –

Evaporation and Air Movement Let’s take a look at this process, click on the umbrella!!!  Water vapors in the air cause humidity. Humidity and temperature combined causes moving air masses, which results in weather fronts.  A front refers to the “front or leading” edge of a moving air mass: Cold Front – leading edge of a mass of cool air Warm Front – leading edge of a mass of warm air

Hurricanes n Weather Fronts can lead to severe weather, such as Hurricanes. n Hurricanes are large, violent tropical storms with wind speeds greater than 117km/hr n Hurricanes begin as thunderstorms over warm water, the heat from the water, wind, and moisture help fuel the storm.

Hurricanes n Hurricane winds move counterclockwise, while the eye of the storm (middle) remains calm. n Let’s take a look at the movement of a hurricane. – urricane_Ike_by_3D_Weather_Globe&video_id= urricane_Ike_by_3D_Weather_Globe&video_id=49 703http:// urricane_Ike_by_3D_Weather_Globe&video_id=49 703

Lesson Recap: The Sun’s Key Roles The Sun’s Key Roles n Effects on Earth’s weather n Moving Air: The Wind n Evaporation n Hurricanes

Online Resources n atrina.com atrina.com atrina.com n n n s.org/sol.html s.org/sol.html s.org/sol.html n s2universe.org/sun/ solar_atmosphere.h tml s2universe.org/sun/ solar_atmosphere.h tml n st.com/Local/WxM ap.aspx?weather=h dVisSatIRBlend st.com/Local/WxM ap.aspx?weather=h dVisSatIRBlend