Atmosphere atmospheres were then modified over time by various complex factors, resulting in quite different outcomes. The atmospheres of the planets Venus and Mars are primarily composed of carbon dioxide, with small quantities of nitrogen, argon, oxygen and traces of other gases. The composition of Earth's atmosphere is largely governed by the by-products of the life that it sustains. Dry air from Earth's atmosphere contains 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and traces of hydrogen, helium, and other "noble" gases (by volume), but generally a variable amount of water vapor is also present, on average about 1% at
Migration of marine species in the Northern Atlantic Ocean Migration of marine species in the Northern Atlantic Ocean The world's oceans are warming due to climate change. Climate change is caused by three major factors which are the greenhouse effect, variation in the sun's energy that reaches Earth, and changes in reflectivity within Earth's atmosphere and its surface. The greenhouse effect is caused by greenhouse gases that absorb sunlight. Energy from the sun that reaches Earth is either retained or sent into space. Greenhouse gases in Earth's atmosphere such as carbon dioxide, methane, and water vapor absorb energy which cause a blanketing effect that warms the earth. Aerosols such