ESS200A
Prof. Jin-Yi Yu
Why Large Greenhouse Effect On Venus?
q Venus is too close to the Sun
è Venus temperature is very
high
è Very difficult for Venus’s
atmosphere to get saturated in water vapor
è Evaporation keep on bringing
water vapor into Venus’s atmosphere
è Greenhouse effect is very
large
è A “run away” greenhouse
happened on Venus
è Water vapor is dissociated into hydrogen and oxygen
è Hydrogen then escaped to space
and oxygen reacted with carbon to form carbon dioxide
è No water left on Venus (and no more chemical weathering)