Climatic control of bedrock river incision

摘要: Bedrock river incision drives the development of much Earth's surface topography, and thereby shapes structure mountain belts modulates habitability through its effects on soil erosion, nutrient fluxes global climate. Although it has long been expected that rates should depend strongly precipitation rates, quantifying bedrock proved difficult, partly because are difficult to measure non-climatic factors can obscure climatic at sites where have measured. Here we present measurements across one steepest rainfall gradients, which show do indeed influence long-term rates. We apply a widely used empirical law for series rivers Hawaiian island Kaua'i, mean annual ranges from 0.5 metres 9.5 (ref. 12)-over 70 per cent range-and averaged over millions years be inferred depth canyons age volcanic bedrock. Both time-averaged analysis numerical modelling transient reveal efficiency Kaua'i is positively correlated with upstream-averaged provide theoretical context this result by demonstrating our consistent linear dependence stream power, rate energy expenditure flow riverbed. These observations rare evidence long-proposed coupling between climate incision, suggesting previously proposed feedbacks among tectonics may occur.