| Observations from the North and South American Cordillera show that mean and maximum elevations decrease with latitude. A correlation between maximum elevation and ELA has been the impetus behind the glacial 'buzzsaw' hypothesis, which states that glaciers limit the elevation of mountain peaks. However, the expected latitudinal trend in topography in the absence of glacial processes is unknown. We use the CHILD model and NCEP/NCAR precipitation data along the Andes to predict trends in topography. Elevation trends vary along latitude by 2-30 fold, depending on the erosional and hydrological model parameterization. Trends generated using stochastic storm generation vary significantly from those generated using mean annual precipitation (MAP) suggesting that MAP may not capture the true geomorphic efficiency of the modern climate system. Geomorphic efficiency varies across the orogen as a result of orographic effects. Our results provide further evidence in support of climate's control on erosion processes and topography. |
