Erosion and landslides along the Rio Coca in Ecuador, February 9, 2023. (Amy East, USGS).
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
Post-Fire Sediment Research at the Pacific Coastal and Marine Science Center
Assessing River Erosion and Sedimentation in Ecuador
Klamath Dam Removal Studies
Sediment Transport in Coastal Environments
Landscape Response to Disturbance
Coastal watershed and estuary restoration in the Monterey Bay area
Coastal and Marine Geohazards of the U.S. West Coast and Alaska
USGS science supporting the Elwha River Restoration Project
Dam removal: synthesis of ecological and physical responses
Bathymetry and Acoustic Backscatter data for Jenkinson Lake, California collected during three USGS field activities, 2022-604-FA, 2022-649-FA, and 2023-634-FA
Suspended-sediment concentration and grain size in the San Lorenzo River, coastal California
Digital Surface Models and orthomosaic images from UAS surveys of Jenkinson Lake, El Dorado County, CA
Radiocarbon age dating of biological material from cores collected off British Columbia, Canada and southeastern Alaska, U.S. along the Queen Charlotte-Fairweather fault zone
Lead, Radium, Cesium, and Thorium isotope activity in sediment samples from Los Padres reservoir, Carmel River watershed, California
Topographic survey data and digital elevation model of Oxbow Reservoir, Placer County, California, October 2022
Grain-size data for sediment samples collected in Whiskeytown Lake, northern California, in 2018 and 2019
Sediment grain-size data from the Klamath estuary, California
Rain measurements in and near the Dolan Fire Area, Los Padres National Forest, California, 2022 to 2023
Grain size and charcoal abundance in sediment samples from Los Padres reservoir, Carmel River watershed, California
Field-verified inventory of postfire hydrologic response for the 2020 CZU Lightning Complex, River, Camel, and Dolan Fires following a 26-29 January 2021 atmospheric river storm sequence
Aeolian and drainage classification data for various archaeological sites in Grand Canyon National Park along the Colorado River from 1973 to 2022
Colored shaded-relief bathymetric map and surrounding aerial imagery of Whiskeytown Lake, California
Erosion and landslides along the Rio Coca in Ecuador, February 9, 2023. (Amy East, USGS).
In the aftermath of the 2018 Carr Fire, northern California, sediment has eroded from burned hillslopes and accumulated in some areas of Whiskeytown Lake. A recent sediment deposit is shown here in the Whiskey Creek section of the lake.
In the aftermath of the 2018 Carr Fire, northern California, sediment has eroded from burned hillslopes and accumulated in some areas of Whiskeytown Lake. A recent sediment deposit is shown here in the Whiskey Creek section of the lake.
Carmel River channel in the former reservoir above San Clemente Dam in Monterey, California.
Carmel River channel in the former reservoir above San Clemente Dam in Monterey, California.
Postfire sediment mobilization and its downstream implications across California, 1984 – 2021
Remote sensing large-wood storage downstream of reservoirs during and after dam removal: Elwha River, Washington, USA
Post-fire sediment yield from a central California watershed: Field measurements and validation of the WEPP model
Major fluvial erosion and a 500-Mt sediment pulse triggered by lava-dam failure, Río Coca, Ecuador
Shifted sediment-transport regimes by climate change and amplified hydrological variability in cryosphere-fed rivers
A watershed moment for western U.S. dams
Postfire hydrologic response along the central California (USA) coast: Insights for the emergency assessment of postfire debris-flow hazards
Archaeological sites in Grand Canyon National Park along the Colorado River are eroding owing to six decades of Glen Canyon Dam operations
Six years of fluvial response to a large dam removal on the Carmel River, California, USA
Midwinter dry spells amplify post-fire snowpack decline
Warming-driven erosion and sediment transport in cold regions
Measuring and attributing sedimentary and geomorphic responses to modern climate change: Challenges and opportunities
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
Post-Fire Sediment Research at the Pacific Coastal and Marine Science Center
Assessing River Erosion and Sedimentation in Ecuador
Klamath Dam Removal Studies
Sediment Transport in Coastal Environments
Landscape Response to Disturbance
Coastal watershed and estuary restoration in the Monterey Bay area
Coastal and Marine Geohazards of the U.S. West Coast and Alaska
USGS science supporting the Elwha River Restoration Project
Dam removal: synthesis of ecological and physical responses
Bathymetry and Acoustic Backscatter data for Jenkinson Lake, California collected during three USGS field activities, 2022-604-FA, 2022-649-FA, and 2023-634-FA
Suspended-sediment concentration and grain size in the San Lorenzo River, coastal California
Digital Surface Models and orthomosaic images from UAS surveys of Jenkinson Lake, El Dorado County, CA
Radiocarbon age dating of biological material from cores collected off British Columbia, Canada and southeastern Alaska, U.S. along the Queen Charlotte-Fairweather fault zone
Lead, Radium, Cesium, and Thorium isotope activity in sediment samples from Los Padres reservoir, Carmel River watershed, California
Topographic survey data and digital elevation model of Oxbow Reservoir, Placer County, California, October 2022
Grain-size data for sediment samples collected in Whiskeytown Lake, northern California, in 2018 and 2019
Sediment grain-size data from the Klamath estuary, California
Rain measurements in and near the Dolan Fire Area, Los Padres National Forest, California, 2022 to 2023
Grain size and charcoal abundance in sediment samples from Los Padres reservoir, Carmel River watershed, California
Field-verified inventory of postfire hydrologic response for the 2020 CZU Lightning Complex, River, Camel, and Dolan Fires following a 26-29 January 2021 atmospheric river storm sequence
Aeolian and drainage classification data for various archaeological sites in Grand Canyon National Park along the Colorado River from 1973 to 2022
Colored shaded-relief bathymetric map and surrounding aerial imagery of Whiskeytown Lake, California
Erosion and landslides along the Rio Coca in Ecuador, February 9, 2023. (Amy East, USGS).
Erosion and landslides along the Rio Coca in Ecuador, February 9, 2023. (Amy East, USGS).
In the aftermath of the 2018 Carr Fire, northern California, sediment has eroded from burned hillslopes and accumulated in some areas of Whiskeytown Lake. A recent sediment deposit is shown here in the Whiskey Creek section of the lake.
In the aftermath of the 2018 Carr Fire, northern California, sediment has eroded from burned hillslopes and accumulated in some areas of Whiskeytown Lake. A recent sediment deposit is shown here in the Whiskey Creek section of the lake.
Carmel River channel in the former reservoir above San Clemente Dam in Monterey, California.
Carmel River channel in the former reservoir above San Clemente Dam in Monterey, California.
Postfire sediment mobilization and its downstream implications across California, 1984 – 2021
Remote sensing large-wood storage downstream of reservoirs during and after dam removal: Elwha River, Washington, USA
Post-fire sediment yield from a central California watershed: Field measurements and validation of the WEPP model
Major fluvial erosion and a 500-Mt sediment pulse triggered by lava-dam failure, Río Coca, Ecuador
Shifted sediment-transport regimes by climate change and amplified hydrological variability in cryosphere-fed rivers
A watershed moment for western U.S. dams
Postfire hydrologic response along the central California (USA) coast: Insights for the emergency assessment of postfire debris-flow hazards
Archaeological sites in Grand Canyon National Park along the Colorado River are eroding owing to six decades of Glen Canyon Dam operations
Six years of fluvial response to a large dam removal on the Carmel River, California, USA
Midwinter dry spells amplify post-fire snowpack decline
Warming-driven erosion and sediment transport in cold regions
Measuring and attributing sedimentary and geomorphic responses to modern climate change: Challenges and opportunities
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.