Global Warming - VenusDiscuss how the atmosphere of Venus can be used to illustrate the danger of extreme global warming.
Venus has an atmosphere that is 90 times that of Earth's. Consequently surface temperatures are considerably higher, hot enough to melt lead. Its dense carbon dioxide atmosphere acts as a greenhouse gas to keep temperatures high. The average surface temperature on Venus is 462°C compared to 14°C on Earth.
Understanding the conditions that led to Venus having such an atmosphere are important to some astronomers.
There are several reasons for this and can be discussed.
- Venus is 1/3 nearer the Sun than the Earth. This is a good reason why it is hotter.
- Very slow rotation spin
- Venus lacks a carbon cycle so that carbon is stored in the oceans , rocks and life.
- Lack of plate tectonics to vent internal heat.
- Radar mapping has detected large number of volcanoes (no evidence that these are active)
- Some have proposed that Venus once had a water surface but this was boiled up.
- Lack of a magnetic field allowed some atmospheric elements such as hydrogen to evaporate into space.
|AU from Sun||1 AU||0.72 AU|
|Km from Sun||149,600,000 km||108,000,000 km|
|Diameter||12,750 km||12,100 km|
|Rotation (Day)||23h,56m,4s||243 days|
|Orbit (Year)||365.25 days||224 days|
|No. of Moons||1||0|
|Tilt of Axis||23.5°||177°|
|Gravity Earth =1)||1||0.9|