Greenhouse Effect Questions

1a) Three forms of radiation from the sun are infrared radiation, ultraviolet radiation and visible light.
1b) Infrared radiation has the longer wavelengths while ultraviolet radiation has the shorter wavelenghts.
2a) Most of the sunlight that reaches Earth is scattered through the atmosphere. The sunlight is scattered by the gas molecules in the atmosphere.
2b) About 25% of the incoming sunlight is reflected back into space by clouds, dust and gases in the atmosphere.
2c) When the sunsets, the sky looks red because the sunlight has to pass through a thicker part of the atmoshpere. As the light is scattered through the atmosphere, more of the blue end of the spectrum is removed so the result is more reds and oranges. Scattering causes the differences in colors when the sun is at different points in the sky.
3a) The energy that is absorbed by the Earth is radiated back into the atmosphere as infrared radiation. This radiation can't travel all the way through the atmosphere, so it is absorbed by different gases in the atmosphere. As the radiated energy heats the gases, they form a "blanket" around the Earth holding heat to the ground.
3b) If the Earth didn't have the greenhouse effect, we would all be dead. As humans, we need the greenhouse effect to survive. It provides us with heat and allows many of the substance we need to survive to prosper. Although we need the effect to live, to much of it can hurt us. There is a great increase in greenhouse gases in the atmosphere and the increase is whats harmful, not the original greenhouse effect. Without the greenhouse effect, there would be barely any life on Earth.