Re:Investing Prophet Jeremy Grantham Takes Aim at Climate Ch...
by tfehring on Friday January 18, 2019 @02:33PM
(#18942191)
> Topsoil should properly be measured in volume, not distance.
Presumably topsoil generation is proportional to land area, and volume per unit area reduces to distance. 3 cm per 1000 years is equivalent to 30 m^3 per km^2 per year.
That said, the number still seems wrong. Table 5.2 in [0] indicates that regeneration rates range from 0.25 mm/year to 2.0 mm/year. 3 cm per 1000 years is equivalent to 0.03 mm per year, almost an order of magnitude lower than the lowest rate in that table.
Presumably topsoil generation is proportional to land area, and volume per unit area reduces to distance. 3 cm per 1000 years is equivalent to 30 m^3 per km^2 per year.
That said, the number still seems wrong. Table 5.2 in [0] indicates that regeneration rates range from 0.25 mm/year to 2.0 mm/year. 3 cm per 1000 years is equivalent to 0.03 mm per year, almost an order of magnitude lower than the lowest rate in that table.
[0] http://www.fao.org/docrep/009/t0733e/T0733E06.htm