The sub-categories are
Atmosphere: This category is about the air we and other beings breath, and where all weather happens. For current monitoring purposes, Atmosphere is sub-categorised according to types of green house gases — including Carbon dioxide, Methane, Carbon monoxide and Water vapour.
Biosphere: Where and the way the atmosphere, the soil and the water interact. This is the most important subject, but it is the one which is the most complex and of which people know the least.
Land: Forests, farmlands, prairies, savannas, mountains.
Species: Humans, bacteria, fungi, trees, algae — all of them in the end. But we are only just at the start so we are using a simple list at this point.
Water: Oceans, Rivers and lakes, Groundwater, Glaciers and snow.
TITLES:
