Amy East
I study how landscapes change over time, focusing on response to hydroclimatic and anthropogenic disturbances. These studies inform resource management as well as fundamental understanding of earth-surface processes. I am also interested in how sediment moves from source to sink, and how the sedimentary record reflects changes in sediment supply and transport.
Research Topics
Landscape Response to Climate Change
Climatic changes associated with modern global warming have been documented widely, but physical landscape responses are poorly understood. Landscape signals of modern climate change relate to human health and safety, infrastructure, water security, and ecosystems. Our project investigates landscape responses to modern climate change, primarily in the western US, focusing on slope failures, watershed sediment yields, river morphology, and aeolian (wind-blown) sediment mobilization.
Post-Fire Sediment Mobilization
Watershed sediment yields increase after fire, but by how much and with what driving factors is not well understood for some regions. Our group studies several CA wildfires, monitoring sediment yield and related processes. We have studied landscape change after seven California fires spanning 2016 to 2022.
Effects of Large Dam Removal
Colleagues and I have studied river response to large dam removals on the Elwha River, WA, and Carmel River, CA, and study the Klamath River (CA and OR) preparing for dam removals there. I helped lead a USGS Powell Center working group on the state of dam-removal science.
Landscape Response to Hydroclimatic Extremes
Western US landscapes export large sediment fluxes, due to steep terrain, tectonic activity, and potential for extreme rain. I study landscape response to hydroclimatic disturbances—drought and extreme rain. We studied sediment export from the San Lorenzo River, CA, from record rainfall in 2017; and debris flows caused by intense rain in 2018 over the Tuolumne basin. Understanding such disturbances is critical to constraining effects of extreme events on landscapes and sediment budgets.
Landscape Evolution in the Colorado River Ecosystem
From 2003 to 2017 I studied connectivity among fluvial, aeolian, and hillslope processes in the Colorado River corridor, AZ. Since 1963, dam operations have altered flows and sediment supply in the Colorado River, Grand Canyon National Park. Loss of sandbars in the dammed river reduces windblown sand supply to aeolian dunes, affecting archaeological-site stability and ecosystem properties.
Aeolian Landscape Stability
Our work quantified sediment accumulation and landscape stability in areas of the California desert considered for solar-energy projects. I also studied aeolian landscapes on the Navajo Nation, where during drought wind-blown sand mobility has destabilized ground surfaces, endangering housing and transportation, jeopardizing grazing lands, and impacting air quality.
Professional Experience
Research Geologist, 2006-present: USGS Coastal and Marine Hazards and Resources Program, Santa Cruz, CA, Principal Investigator of Landscape Response to Disturbance project
Editor-in-Chief, January 2019-present: Journal of Geophysical Research, Earth Surface
Postdoctoral Researcher, 2003-2006: USGS/UC Santa Cruz
Education and Certifications
Ph.D., Geology and Geophysics, 2003: MIT/Woods Hole Oceanographic Institution
B.S., Geological Sciences, 1997: Tufts University
Science and Products
Vegetation, substrate, and eolian sediment transport at Teesto Wash, Navajo Nation, 2009-2012
Influence of the Amlia fracture zone on the evolution of the Aleutian Terrace forearc basin, central Aleutian subduction zone
During Pliocene to Quaternary time, the central Aleutian forearc basin evolved in response to a combination of tectonic and climatic factors. Initially, along-trench transport of sediment and accretion of a frontal prism created the accommodation space to allow forearc basin deposition. Transport of sufficient sediment to overtop the bathymetrically high Amlia fracture zone and reach the central A
Effects of river regulation on aeolian landscapes, Colorado River, southwestern USA
Channel evolution on the dammed Elwha River, Washington, USA
Arc-continent collision and the formation of continental crust: A new geochemical and isotopic record from the Ordovician Tyrone Igneous Complex, Ireland
Sedimentation processes in a coral reef embayment: Hanalei Bay, Kauai
Supply and dispersal of flood sediment from a steep, tropical watershed: Hanalei Bay, Kauai, Hawaii, USA
Channel Evolution on the Lower Elwha River, Washington, 1939-2006
Application of sedimentary-structure interpretation to geoarchaeological investigations in the Colorado River Corridor, Grand Canyon, Arizona, USA
The role of aeolian sediment in the preservation of archaeological sites in the Colorado River corridor, Grand Canyon, Arizona: Final report on research activities, 2003-2006
Sedimentary processes in modern and ancient oceanic arc settings: evidence from the Jurassic Talkeetna Formation of Alaska and the Mariana and Tonga Arcs, western Pacific
Stratigraphic and geochemical evolution of an oceanic arc upper crustal section: The Jurassic Talkeetna Volcanic Formation, south-central Alaska
Non-USGS Publications**
ISSN: 0197-9337 , 1096-9837 (online) , 1096-9837; DOI: 10.1002/esp.5561
Draut, A.E., and Clift, P.D., 2001, Geochemical evolution of arc magmatism during arc-continent collision, South Mayo, Ireland: Geology v. 29 (6): 543–546. doi: 10.1130/0091-7613(2001)029<0543:GEOAMD>2.0.CO;2
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Vegetation, substrate, and eolian sediment transport at Teesto Wash, Navajo Nation, 2009-2012
Influence of the Amlia fracture zone on the evolution of the Aleutian Terrace forearc basin, central Aleutian subduction zone
During Pliocene to Quaternary time, the central Aleutian forearc basin evolved in response to a combination of tectonic and climatic factors. Initially, along-trench transport of sediment and accretion of a frontal prism created the accommodation space to allow forearc basin deposition. Transport of sufficient sediment to overtop the bathymetrically high Amlia fracture zone and reach the central A
Effects of river regulation on aeolian landscapes, Colorado River, southwestern USA
Channel evolution on the dammed Elwha River, Washington, USA
Arc-continent collision and the formation of continental crust: A new geochemical and isotopic record from the Ordovician Tyrone Igneous Complex, Ireland
Sedimentation processes in a coral reef embayment: Hanalei Bay, Kauai
Supply and dispersal of flood sediment from a steep, tropical watershed: Hanalei Bay, Kauai, Hawaii, USA
Channel Evolution on the Lower Elwha River, Washington, 1939-2006
Application of sedimentary-structure interpretation to geoarchaeological investigations in the Colorado River Corridor, Grand Canyon, Arizona, USA
The role of aeolian sediment in the preservation of archaeological sites in the Colorado River corridor, Grand Canyon, Arizona: Final report on research activities, 2003-2006
Sedimentary processes in modern and ancient oceanic arc settings: evidence from the Jurassic Talkeetna Formation of Alaska and the Mariana and Tonga Arcs, western Pacific
Stratigraphic and geochemical evolution of an oceanic arc upper crustal section: The Jurassic Talkeetna Volcanic Formation, south-central Alaska
Non-USGS Publications**
ISSN: 0197-9337 , 1096-9837 (online) , 1096-9837; DOI: 10.1002/esp.5561
Draut, A.E., and Clift, P.D., 2001, Geochemical evolution of arc magmatism during arc-continent collision, South Mayo, Ireland: Geology v. 29 (6): 543–546. doi: 10.1130/0091-7613(2001)029<0543:GEOAMD>2.0.CO;2
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.