Rivers and glaciers erode the landscape at similar rates, according to a study published online in Nature Geoscience. Previous studies held that glaciers eroded the Earth's surface at a faster rate.
Michele Koppes and David Montgomery compiled data on rates of erosion from rivers and glaciers around the world. They found that once they accounted for differences in the relative areas covered by glacial catchments and river basins, the amount of the surface eroded by glaciers and rivers fell into the same range ? from less than 1 to over 10 mm per year. The authors also report that the highest rates of erosion were found to occur in landscapes that have recently been disturbed, either through volcanic eruptions or the rapid retreat of glaciers along the coast.
The high end of erosion rates from rivers and glaciers is comparable to the rates of erosion reported from agricultural lands, suggesting that farming has a substantial impact on the landscape.