Climate is widely thought to regulate erosion rates, but the relationships
among precipitation, temperature, and erosion rate have remained speculativ
e, because long-term erosion rates have been difficult to measure. We used
cosmogenic nuclides to measure long-term erosion rates at climatically dive
rse sites in the Sierra Nevada, California, spanning 20-180 cm/yr in annual
precipitation and;4-15 degreesC in mean annual temperature. Average erosio
n rates vary by only 2.5 fold across these sites and are not correlated wit
h climate, indicating that climate only weakly regulates nonglacial erosion
rates in mountainous granitic terrain.