Weather Unit

1. Weather Unit 13.1 - A Closer Look at the Earth 13.2 – Earth’s Energy Balance 13.3 – Seasons & the Angle of Sunlight http://youtube.com/watch?v=s76Qn7bpCsQ&feature=related

2. Weather and Climate • Weather… What is It? • Day to day environmental conditions • Examples: • Rainy / snowy • cloudy / sunny • Windy / calm • Climate • Environmental condition averaged over many years • Examples: • Average rainfall • Average daily temperature

3. Variables used to describe weather and climate: • Temperature • Wind Speed and Direction • Visibility • Cloud cover • Atmospheric Pressure • Dew Point • Humidity

4. Formation of Weather and Climate • Is the weather is the same here as it is in Saint John? Why or not? • Geographically, how is Saint John different than Fredericton? • Would any of these geographical features affect the weather in that area? If so which ones and how? Here are the facts: Components that influence weather and climate include: • Latitude and Longitude • Atmosphere • Oceans • Land Masses

5. Components that influence weather and climate include: Latitude and Longitude Atmosphere (later) Oceans (later) Land Masses (later) Latitude & Longitude Influences on Weather and Climate and Latitude/Longitude

6. Longitude (Meridians) • Angle of measure east or west of the Prime Meridian • Imaginary vertical lines Label on Your Map • Prime Meridian 0o (Greenwich, England) • International Dateline 180o

7. Latitude (Parallels) • Angle of measure north or south of the Equator • Imaginary horizontal lines Label on Your Map: (BLM 13.1A) • Equator 0o • North Pole 90oN • South Pole 90oS • Arctic Circle 67.5oN • Antarctic Circle 67.5oS • Tropic of Cancer 23.5oN • Tropic of Capricorn 23.5oS

8. Mapping Activity • Short Worksheet – • Part A: students to determine latitude and longitude of a location • Part B: students to determine location based on latitude and longitude.

9. 13.2 – Energy Systems Energy (heat or light) is transferred in one of the following ways: • Radiation • Convection • Advection • Conduction

10. Radiation • Where does it come from? • produced by nuclear fusion reactions in the sun • How does Solar Energy reach Earth? • Radiant energy travels in waves of different energy levels, collectively known as the Electromagnetic Spectrum • In order from lowest to highest frequency: • Radio • Microwave • Infrared • Visible • Ultraviolet • X-rays • Gamma

11. Advection • Transfer of energy through the collision of particles in a liquid or gas • Energy moves horizontally

12. Conduction • the transfer of energy which occurs when a particle with high energy hits a particle with lower energy • thus energy is passed through an object from atom to atom • only occurs in solids, since the particles must be close together for frequent collisions to occur readily

13. Heat Capacity • a measure of how much heat a substance must absorb to increase its temperature by 1 o C • if a substance absorbs a lot of heat, yet its temperature rises slowly, then it has a high heat capacity (e.g. water) • if a substance absorbs a lot of heat, and its temperature rises rapidly, then it has a liow heat capacity (e.g. metals) • See Figure 5 p.506.

14. Heat Sinks • an object which absorbs large amounts of energy • substances with high heat capacities make a good heat sink • e.g water, concrete

15. Absorption and Reflection • solar energy entering the atmosphere can be either absorbed or reflected • approximately 70% in total is absorbed • 44% heat the Earth’s land surface and air • 25% heat the water and evaporate some water • 1% creates wind • Less than 1% is used for photosynthesis • approximately 30 % is reflected (air 6%, clouds 20%, earth 4%)

17. Why is Solar Energy Important? • all forms of life on earth are dependent on solar energy for life • needed for plants to grow and to keep earth warm enough for survival • Reminder: less than 1% is used by Photosynthesis. • PHOTOSYNTHESIS – The process by which green plants use sunlight to produce sugar. CO2 + 2H2O + sunlight ---> O2 + C6H12O6 + H2Oor...carbon dioxide + water + sunlight ---> oxygen + carbohydrate + water

18. 13.3 – Seasons and the Angle of Sunlight • Video: Bill Nye (Seasons) • Handout: Seasons Worksheet (24 min)

19. 13.3 - Reason for the Seasons • The average tilt, 23.5o, of the Earth is the reason for the seasons) • As the Earth revolves around the Sun, the seasons in the northern and southern hemispheres are opposite. http://geovideos.fliggo.com/video/NY5Lxu6q

20. Earth’s Rotation and Revolution • Rotation (24 hours) • The Earth rotates on its axis • The axis (imaginary line) runs North to South • 23.5o angle • One Earth rotation takes one day • Rotate East to West • Revolution (365 Days) • The Earth revolves around the Sun • The movement of one object traveling around another • It takes the earth one year to revolve (travel) around the Sun counter clockwise Any ideas as to how earth’s tilt towards or away from the sun can effect the 4 season’s we experience here in Canada??

21. Earth’s Seasons • Tilt of the Earth’s axis towards or away from the sun creates the seasons SUMMER (Northern Hemisphere) When the north pole tilts toward thesun, it gets more radiation – more warmth during the summer North Pole Equator Earth South Pole When the north pole tilts toward thesun, the south pole tilts away So when it’s summer in the north, it’s winter in the south WINTER (Southern Hemisphere)

22. Earth’s Seasons • Tilt of the Earth’s axis towards or away from the sun creates the seasons WINTER (Northern Hemisphere) When the north pole tilts away from the sun, it gets less radiation – So it’s colder during the winter North Pole Equator Earth South Pole When the north pole tilts away from thesun, the south pole tilts toward it… When it’s winter in the north, it’s summer in the south SUMMER (Southern Hemisphere)