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Summary

Atmosphere Contents

2. Solar Energy

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Conclusion

The main source of radiation and the only external input to the Earth is from the sun. This solar radiation provides energy for the biosphere, atmospheric and oceanic circulation patterns and the weather systems. We can see only a small part of solar radiation - visible light. There is however a whole spectrum of light ranging from infrared radiation to ultraviolet radiation. Only 45% of the incoming radiation reaches the surface of the Earth, with 25% being reflected back into space by clouds and 25% being absorbed in the atmosphere. Radiation is extremely harmful to life and biological tissues and various processes in the atmosphere actually take out this potentially harmful ultraviolet radiation.

Questions and answers

1. How far is the sun from the Earth?

question 1 answers

2. What powers the sun and what is the average temperature of the photosphere?

question 2 answers

3. What are the crucial roles that solar radiation plays for life on Earth?

question 3 answers

4. What are the two theories of radiation?

question 4 answers

5. What are the four major regions of the radiation spectrum; and at what wavelength does visible radiation occur (i.e. stimulates the colour cones in the retina of the human eye)?

question 5 answers

6. What are the energies of the photons of kJmol at the extremes of visible radiation?

question 6 answers

7. How much of the sun's radiation reaches the surface of the Earth and in what wavelengths does this predominantly occur?

question 7 answers

8. What are the first and second Laws of Thermodynamics?

question 8 answers