Start Date
23-10-2023 3:45 PM
End Date
23-10-2023 5:00 PM
Access Type
Open Access
Abstract
Volcanic ocean islands are well suited for studying climatic controls on erosion because they typically have relatively homogeneous bedrock, dramatic rainfall gradients, and remnant surfaces that constrain their age, initial topography, and vertical motions relative to sea level. In this talk, I’ll examine the influence of rainfall and discharge variability on bedrock river incision on the Hawaiian Island of Kaua‘i. I’ll also present a new compilation of basin-averaged cosmogenic erosion rates measured on ocean islands worldwide, as well as >800 million year-scale basin-averaged erosion rates inferred from eroded canyon volumes and lava flow ages across the Azores, Hawaiian, Cape Verde, and Canary Islands. These erosion rates increase with mean annual rainfall over nearly the full range of rainfall rates experienced on Earth. Yet, the scalings between rainfall and erosion rates vary over millennial vs. million-year timescales and between island chains. I’ll discuss some possible explanations for these discrepancies in climatic control and consider the implications on couplings between orogeny and orography.
Biography
Kim Huppert earned a B.S. in Civil Engineering from Massachusetts Institute of Technology in 2011 and a PhD in Earth and Atmospheric Sciences from MIT in 2017. She is currently an assistant professor in the Department of Earth and Atmospheric Sciences at CUNY City College of New York and Graduate Center, where she teaches courses in geomorphology and geographic information systems. Dr. Huppert and her research group study how the Earth's surface changes over time and how it is shaped by erosion, tectonics, and climate.
Additional Links
ORCID
Islands in the rain: Isolating the influence of rainfall on erosion on volcanic ocean islands
Volcanic ocean islands are well suited for studying climatic controls on erosion because they typically have relatively homogeneous bedrock, dramatic rainfall gradients, and remnant surfaces that constrain their age, initial topography, and vertical motions relative to sea level. In this talk, I’ll examine the influence of rainfall and discharge variability on bedrock river incision on the Hawaiian Island of Kaua‘i. I’ll also present a new compilation of basin-averaged cosmogenic erosion rates measured on ocean islands worldwide, as well as >800 million year-scale basin-averaged erosion rates inferred from eroded canyon volumes and lava flow ages across the Azores, Hawaiian, Cape Verde, and Canary Islands. These erosion rates increase with mean annual rainfall over nearly the full range of rainfall rates experienced on Earth. Yet, the scalings between rainfall and erosion rates vary over millennial vs. million-year timescales and between island chains. I’ll discuss some possible explanations for these discrepancies in climatic control and consider the implications on couplings between orogeny and orography.