Answer:
1. In spite of the enormous transfers of energy into and from the Earth, it maintains a relatively constant temperature because, as a whole, there is little net gain or loss: Earth emits via atmospheric and terrestrial radiation (shifted to longer electromagnetic wavelengths) to space about the same amount of energy as it receives via solar insolation (all forms of electromagnetic radiation).
2. The Sun is 93 million miles away, so sunlight takes 8 and 1/3 minutes to get to us.
3. Thus, about 71 percent of the total incoming solar energy is absorbed by the Earth system. Of the 340 watts per square meter of solar energy that falls on the Earth, 29% is reflected back into space, primarily by clouds, but also by other bright surfaces and the atmosphere itself.
4. The main greenhouse gases are Water vapor, Carbon dioxide, Methane.
5. Albedo is a measure of the reflectivity of the Earth's surface. Ice-albedo feedback is a strong positive feedback in the climate system. Warmer temperatures melt persistent ice masses in high elevations and upper latitudes. Ice reflects some of the solar energy back to space because it is highly reflective.
6. Water vapor and clouds are the major contributors to Earth's greenhouse effect, but a new atmosphere-ocean climate modeling study shows that the planet's temperature ultimately depends on the atmospheric level of carbon dioxide. To get a complete picture of Earth's temperature, scientists combine measurements from the air above land and the ocean surface collected by ships, buoys and sometimes satellites, too. A 'positive' anomaly means the temperature is warmer than the long-term average, a 'negative' anomaly means it's cooler.
7. Some clouds form due to the heating of the Earth's surface. First, the Sun heats the ground, which then heats the air. This warm air is lighter and less dense than the surrounding air, so it begins to rise. When this air rises, it expands because of the lower pressures that exists at higher levels in the atmosphere.
