The surface layer of ground is turf. It is a layer of earth that is covered with grass. Turf is very noticeable because it's the only thing that one sees when one looks at the ground, unless there has been some digging.
turf
The Troposphere. M. West
STRATOSPHERE
the layer of rock that comprises 67% of earths mass
half of earths layer
The earth thinnest layer is the crust.
The crust is the thinnest layer of the Earth.
The original bookies, or people who handle bets, worked at horse races, where the ground is called turf. Thus, they are accountants because they handle money, and since they work on the turf, they are turf accountants.
Actually, the Troposphere Layer can be considered as Earth's first protective layer, because its well-the atmosphere's first layer. You can think of it that way to remember which is Earths first layer.
The layer below the earth's outer layer is mesosphere. It is the 3rd layer.
The earths crust is a part of the outermost layer.
mesosphere