Unit D

Energy Flow in Global Systems


  Conclusion

Solar energy supports life and creates the climates on Earth.


DC.1 The sun and Earth
In this unit, we started out learning about what climate is and how it interacts with the biosphere. We looked at how the sun’s energy is used once it reaches Earth and the net radiation budget. We then looked at climate and how climate affects the different species living on Earth. We learned the difference between weather and climate as well.

Once we finished learning what climate is and how the sun’s energy is used, we learned how the sun’s energy creates climates. We looked at the different factors that create climate, including albedo, insolation, angle of inclination and incidence, length of daylight, and cloud cover, and the different biomes climate creates.

We then took a closer look at thermal energy, learning how it is transferred around the globe by both the atmosphere (the global wind patterns) and the hydrosphere (ocean currents). We learned about specific heat capacity and how it helps the hydrosphere with thermal energy transfer.

Finally, we looked at what climate change and the enhanced greenhouse effect are and their impacts. We learned how human activity is contributing to climate change and the different perspectives we use when assessing human activities.  Strategies for reducing climate and environmental change were explored, and topics of further research outlined.   
DC.2 Protecting Earth

  Review Questions

Complete the following review questions to check your understanding of the concepts you have learned. Make sure you write complete answers to the review questions in your notes. After you have checked your answers, make corrections to your responses (where necessary) to study from.

  1. What is the net radiation budget, and what should it be equal to?

    The net radiation budget is the difference between the amount of incoming solar radiation and outgoing radiation re-emitted from the biosphere. The net radiation budget should always be equal to 0. If it is not equal to 0, then the Earth will either heat up or cool down so that it equals 0 again.
  2. What is the source of the majority of energy on Earth?

  3. What are the three parts of the biosphere?

    The atmosphere, lithosphere, and hydrosphere
  4. What is the difference between weather and climate?

    Weather is the conditions you see at a specific location at a specific time. Climate is the average temperature, precipitation, and amount of sunlight seen over a minimum of 30 years.
  5. Complete the following chart about the different factors affecting climate.

    Factor Effect on Climate and Why
    angle of inclination
    angle of incidence
    time of year
    length of daylight
    cloud cover and atmospheric dust
    albedo
    thermal energy transfer


    Factor Effect on Climate and Why
    angle of inclination
    		As you travel away from the equator, you get more defined and extreme seasons because the solar radiation reaching Earth decreases depending on the time of year. The tilt of Earth affects which hemisphere is facing the sun and receiving more solar radiation.
    angle of incidence
    		As the angle of incidence increases, the average temperature of the area decreases because as you travel away from the equator, this angle increases, decreasing the strength and amount of solar radiation an area receives.
    time of year
    		The time of year affects the angle of incidence, length of daylight, albedo and the amount of solar radiation a location receives.  As you travel farther away from the equator, the time of year as more of an effect on the climate. 
    length of daylight
    		As you travel away from the equator, the average temperature drops during winter months due to less solar radiation because the amount of daylight and solar radiation received varies greatly depending on the season.
    cloud cover and atmospheric dust
    		These can create more precipitation and cooler or warmer temperatures depending on other factors because both reflect incoming solar radiation. They also reflect thermal energy radiated from Earth back to the surface.
    albedo The higher the albedo, the cooler the temperatures. The albedo can vary depending on the season because the higher the albedo, the more solar radiation is reflected and the less that reaches Earth’s surface. Dark colours cause a lower albedo and warmer temperatures, while light colours cause a higher albedo and cooler temperatures.
    thermal energy transfer
    		This transfer can help even out temperatures around Earth. It can also cause colder or warmer climates depending on global wind patterns and ocean currents.

  6. What biomes is Alberta part of?

    The taiga and grassland biomes
  7. How does specific heat capacity affect climate?

    Water has a relatively high specific heat capacity, so it takes lots of thermal energy for water to heat up or cool down. This means it can transfer or absorb lots of thermal energy from the air and land around it without changing its temperature very much. This makes the land and air around water have less variation in temperature. It also means cooler water makes cooler climates, while warmer water makes warmer climates.
  8. A house contains 159 kg of dry air. The furnace has broken and the temperature of the air has fallen from 20 ˚C to 5.0 ˚C. How much energy has been released if the air has a specific heat capacity of 1.00 J/g•˚C?

    Step 1: List your variables.

    «math xmlns=¨http://www.w3.org/1998/Math/MathML¨» «mi»Q«/mi» «mo»=«/mo» «mo»?«/mo» «mspace linebreak=¨newline¨»«/mspace» «mi»m«/mi» «mo»=«/mo» «mn»159«/mn» «mo»§#160;«/mo» «mi»kg«/mi» «/math»

    Note: The mass must be converted to grams to be used in the formula.

    «math xmlns=¨http://www.w3.org/1998/Math/MathML¨» «mtable columnspacing=¨0px¨ columnalign=¨right center left¨» «mtr» «mtd» «mn»1«/mn» «mo»§#160;«/mo» «mn»000«/mn» «mo»§#160;«/mo» «mi mathvariant=¨normal¨»g«/mi» «/mtd» «mtd» «mo»=«/mo» «/mtd» «mtd» «mn»1«/mn» «mo»§#160;«/mo» «mi»kg«/mi» «/mtd» «/mtr» «mtr» «mtd» «mfrac» «mrow» «mn»1«/mn» «mo»§#160;«/mo» «mn»000«/mn» «mo»§#160;«/mo» «mi mathvariant=¨normal¨»g«/mi» «/mrow» «mrow» «mn»1«/mn» «mo»§#160;«/mo» «mi»kg«/mi» «/mrow» «/mfrac» «/mtd» «mtd» «mo»=«/mo» «/mtd» «mtd» «mfrac» «mo»?«/mo» «mrow» «mn»159«/mn» «mo»§#160;«/mo» «mi»kg«/mi» «/mrow» «/mfrac» «/mtd» «/mtr» «/mtable» «/math»

    Now cross-multiply and divide.

    «math xmlns=¨http://www.w3.org/1998/Math/MathML¨» «mtable columnspacing=¨0px¨ columnalign=¨right center left¨» «mtr» «mtd» «mn»1«/mn» «mo»§#160;«/mo» «mn»000«/mn» «mo»§#160;«/mo» «mi mathvariant=¨normal¨»g«/mi» «mo»§#215;«/mo» «mn»159«/mn» «mo»§#160;«/mo» «mi»kg«/mi» «/mtd» «mtd» «mo»=«/mo» «/mtd» «mtd» «mn»159«/mn» «mo»§#160;«/mo» «mn»000«/mn» «/mtd» «/mtr» «mtr» «mtd» «mn»159«/mn» «mo»§#160;«/mo» «mn»000«/mn» «mo»/«/mo» «mn»1«/mn» «/mtd» «mtd» «mo»=«/mo» «/mtd» «mtd» «mn»159«/mn» «mo»§#160;«/mo» «mn»000«/mn» «mo»§#160;«/mo» «mi mathvariant=¨normal¨»g«/mi» «/mtd» «/mtr» «/mtable» «/math»

    Please click here for a refresher on how to do unit conversions.

    «math xmlns=¨http://www.w3.org/1998/Math/MathML¨» «mtable columnspacing=¨0px¨ columnalign=¨right center left¨» «mtr» «mtd» «mi»c«/mi» «/mtd» «mtd» «mo»=«/mo» «/mtd» «mtd» «mn»1«/mn» «mo».«/mo» «mn»00«/mn» «mo»§#160;«/mo» «mi mathvariant=¨normal¨»J«/mi» «mo»/«/mo» «mi mathvariant=¨normal¨»g«/mi» «mo»§#8226;«/mo» «mo»§#176;«/mo» «mi mathvariant=¨normal¨»C«/mi» «/mtd» «/mtr» «mtr» «mtd» «mo»§#8710;«/mo» «mi»t«/mi» «/mtd» «mtd» «mo»=«/mo» «/mtd» «mtd» «mn»20«/mn» «mo»-«/mo» «mn»5«/mn» «mo»=«/mo» «mn»15«/mn» «mo»§#160;«/mo» «mo»§#176;«/mo» «mi mathvariant=¨normal¨»C«/mi» «/mtd» «/mtr» «/mtable» «/math»
    Step 2: Rearrange the formula.

    Q = mcΔt
    Step 3: Substitute the values into the formula.

    Q = mcΔt
    Q = (159 000 g)(1.00 J/g•˚C)(15 ˚C)
    Step 4: Calculate the answer.

    Q = (159 000 g)(1.00 J/g•˚C)(15 ˚C)
    Q = 2 385 000 J

    The energy needs to be rounded to two significant digits, as two digits is the smallest number of digits found in the question. To round this answer to two significant digits, we need to convert it to scientific notation.

    Q = 2.4 x 106 J

    The air in the house has released 2.4 × 106 J of thermal energy.


  9. How does the hydrologic cycle move thermal energy around Earth?

    The hydrologic cycle moves energy around Earth through water evaporating into the atmosphere; as this happens, it is breaking bonds and absorbing thermal energy. It then moves to a different area of Earth and changes back to a solid or liquid state in the form of precipitation. As water moves back into a solid or a liquid, bonds are being formed; this releases thermal energy into the surrounding area. In this way, thermal energy from one area of Earth was moved to a different area.
  10.  Does water change temperature when it changes state?

    No, water does not change temperature as it changes state because the thermal energy is being used to change state rather than raise the temperature of the water.
  11. What is the Coriolis effect, and how does it affect thermal energy transfer in both the atmosphere and hydrosphere?

    The Coriolis effect is when the rotation of Earth causes anything above Earth’s surface to be deflected to the west. This includes wind and ocean currents. Instead of the convection currents in the air or ocean running directly north–south, they run southwest or northwest. It also causes the ocean currents to circle clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere. This affects the thermal energy transfer in both the atmosphere and the hydrosphere as thermal energy does not travel directly from high thermal energy to low thermal energy, instead it is deflected.
  12. How do land and sea breezes differ? What makes them different?

    Land breezes blow from the land to the ocean, while sea breezes blow from the sea to land. In a land breeze, the land is warmer than the body of water, so the convection current runs from the land up, out over the water, down, and back to land as it cools. In a sea breeze, the body of water is warmer, so the convection current runs from the water up, toward the land, down, and back out to the water as it cools. Land tends to be warmer during the day, as it warms up faster in the sun, and the water tends to be warmer at night, as it takes longer to cool down.
  13. What tool would you use to compare two different climates?

    A climatograph
  14. What factors are thought to create natural climate change?

    Earth’s tilt and orbit, continental drift, and feedback loops
  15. What is the greenhouse effect? What are the greenhouse gases?

    The greenhouse effect is when the thermal energy emitted by Earth is reflected back to the surface by greenhouse gases. This helps to keep Earth in a habitable temperature range. Greenhouse gases are those gases that have a higher ability to absorb and re-emit thermal energy. These include water vapour, carbon dioxide, nitrous oxide, and methane.
  16. How do we know human activity is affecting climate change?

    Using climate models, the climate change seen up to 1950 can be explained by natural causes. After 1950, the only way to interpret the climate change we are currently seeing is to include human activity. Climate change has occurred 10 times faster in the last 100 years than any point before. This matches with when the industrial revolution occurred and human activity started to increase drastically.
  17. What international organizations and agreements is Canada part of?

    Canada is part of the UNFCCC and the Paris Agreement. We were part of the Montreal Protocol until its completion, and we have withdrawn from the Kyoto Protocol.
  18. What are the potential impacts of climate change?

    The potential impacts of climate change are an increase in global temperature, changing and unpredictable weather patterns, including an increase in storms and natural disasters, and a decrease in biodiversity. Each of these potential impacts creates more impacts of their own, such as farmers being forced to change the crops they grow and an increase in disease-spreading insects.
  19. What are two things you could change in your life to reduce your greenhouse gas emissions?

    Your answer will be a variation of the following. There are lots of examples, so if you are unsure if your idea is an example or not, please contact your teacher to check! Some examples are

    • taking public transportation
    • buying locally to reduce transportation of goods
    • walking or biking when possible
    • turning off lights in rooms not being used
    • turning down your furnace
    • unplugging appliances not in use
    • turning off the water when not in use


  Unit D Project

Complete the following Unit D Project to wrap up this unit. You will find a project like this one at the end of every unit in the course. These projects are meant to help you put the concepts you have learned in the unit together. There are two options for this project. Please choose only one to complete. Once you have chosen the one you wish to complete, please make sure you read the instructions carefully and follow the rubric. Make sure you ask your teacher if you have any questions.

Congratulations! You only have this project, the Final Review Assignment and the Final Exam left!