OUTCOME
By the end of the lesson you will be able to explain the Earth's energy budget. You will understand how certain molecules in the atmosphere contribute to the temperature of the Earth. You will also be able to describe what a positive feedback loop is.
The Earth's Temperature is in Thermal Equilibrium and is determined by the balance between Energy absorbed by the sun and energy radiated out into space
Greenhouses gases can absorb Infrared Radiation and Re-emit that radiation, reducing the amount of thermal radiation that emitted into space
LEARNING TASKS
Explain
What are the key features of Methane, Water and Carbon Dioxide that make them so effective at absorbing Infrared Radiation (compared to gases such as Oxygen and Nitrogen)
Describe an example of a positive feedback loop and a negative feedback loop. The runaway Greenhouse effect was caused by a positive feedback loop tipping over the edge.
Explore and Elaborate
After watching this screencast, redraw the diagram on page 37 of your text, showing some possible changes in the thermal radiation transfer values if the greenhouse gas component was increased. Justify your choices
Evaluate
Do the following Questions:
Ex 2.3