Earth is (mostly) flat: Apportionment of the flux of continental sediment over millennial time scales: COMMENT

Recent synthesis of ¹⁰Be-derived denudation rates by Willenbring et al. (2013) suggests that the “flat” areas of the world, those with average slopes of <∼100 m/km and representing ∼90% of Earth’s land surface, have adequately high rates of denudation to produce most of the sediment transported to the world’s oceans. This finding is based on the product of interpolated denudation rates (L/T) over the world’s drainage areas (L²) using landscape slope as the controlling variable. We suggest that these findings are incorrect on several grounds.