How does solar energy cause wind?
2 Answers
Solar energy causes pressure differences at the atmosphere and this causes wind formation.
Explanation:
Because of the solar energy (incoming short wave radiation), earth surface heats up. Air near the ground tends to gain heat from the earth surface. When air is heated, it expands and starts to rise. When air rises pressure decrease at the surface.
At the same time at the higher levels cooled air tends to sink and at the sinking point pressure increases at the surface.
This horizontal pressure differences causes air to move from high pressure to low pressure. Therefore winds happen. :)
Solar energy causes wind due to it's affect on air pressure.
Explanation:
Wind is caused by air pressure gradient, basically air moving from an area of high pressure to low pressure. The Gay-Lussac's Law tells us that as heat increases pressure increases. Therefore areas that are heated more will have higher pressures. This is why the pressure at the Equator is higher than the pressure at the poles. This is what causes your prevailing winds.
If you have an air parcel that heats up faster within the air mass that it is in, it will expand. This is Charles' Law, volume and temperature are proportional. The difference between this situation and the general situation above is that in this cause the air parcel can expand because it heats more than the surround air whereas all the air at the equator is heated so it is all trying to expand increasing the temperature since the volume basically cannot change.
When the volume of an air parcel increases the pressure of that parcel will decrease. This is Boyle's Law, which states that pressure is inversely proportional to volume.
The processes that I described in the 2nd and 3rd paragraphs is what give us lows and highs, which affect the flow of winds on a synoptic scale but not planetary scale.
