1. Atmosphere and Change
Learning objectives: To be able to understand the external factors that affect the energy balance.

2. Recap
From memory sketch the global energy balance

3. What questions could you ask about this data?

4. Key terms Solar radiation Albedo Milankovich cycles
Global brightenning
Global dimming

5. External forcings Cause Description Impact on the energy balance
Change in eccentricity / obliquity / precision
Change in solar activity
Volcanic activity

6. Orbital oscillations –more or less sunlight reaching the Earth.

7. Eccentricity Cycle of about 100 000 years
Ranges from 0%- 5% eccentricity
Changes the distance the SW radiation must travel from the Sun to reach the Earth
This changes the amount of radiation at different seasons

8. Current tilt of the Earth is 23.5 degrees
Accounts for the seasons
A greater tilt = greater range in the seasons

10. Sun spot activity P147 Paul Guinness
Read and makes notes on the causes and effects of sunspot activity

11. Albedo of the atmosphere
The proportion of the solar energy reflected from the Earth back into space
Use p148 to consider the albedo at each biome

12. Volcanic activity

13. Changes in long wave radiation returned to space