Evaluate evidence and uncertainty when discussing the Earth's early atmosphere.

In the subtopic The Earth's early atmosphere, this learning objective focuses on evaluate evidence and uncertainty when discussing the Earth's early atmosphere. Within The composition and evolution of the Earth's atmosphere, students should explain this idea in the exact curriculum context rather than as an isolated fact. Approved keywords for this objective include early atmosphere and evidence. early atmosphere means the composition of the Earth's atmosphere during its initial formation, likely rich in carbon dioxide and lacking oxygen. Avoid students often state that the Earth's early atmosphere contained significant amounts of oxygen; instead remember that the Earth's early atmosphere is believed to have mainly contained carbon dioxide with little or no oxygen. For exam answers, when evaluating evidence about the Earth's early atmosphere, consider the sources of information and the uncertainties involved.