The bottom layer of the atmosphere. 6 miles high
Treaty/protocol that deals with stopping the production of ozone depleting chemicals
Heating of a planet's atmosphere that occurs when outgoing infra-red radiation is trapped by certain gases.
Changes in the shape earth's orbit and tilt that cause glacial periods and interglacial periods.
a reservoir that uptakes a chemical element or compound from another part of its cycle.
How reflective a surface is.
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