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
River-channel topography, grain size, and turbidity records from the Carmel River, California, before, during, and after removal of San Clemente Dam (ver. 2.0, March 2022)
Polycyclic aromatic hydrocarbons (PAHs) and suspended sediment concentrations in the San Lorenzo River, Santa Cruz, California, USA
Rain measurements in and near the CZU Lightning Complex Fire area, Santa Cruz Mountains, California, 2020 to 2021
Sediment grain-size data from the Klamath estuary, California
Luminescence, weather, and grain-size data from eastern Chuckwalla Valley, Riverside County, California
Bathymetry, topography and orthomosaic imagery for Whiskeytown Lake, northern California (ver. 2.0, July 2021)
Grain-size data for sediment samples collected in Whiskeytown Lake, northern California, in 2018 and 2019
Chirp sub-bottom data collected in 2019 in Whiskeytown Lake, California during USGS field activity 2018-686-FA
Field, geotechnical, and meteorological data of the 22 March 2018 narrow cold frontal rainband (NCFR) and its effects, Tuolumne River canyon, Sierra Nevada Foothills, California
Floodplain data from the Hoh, Elwha, Queets, and Quinault Rivers in Olympic National Park, 1939-2013
River Valley Sediment Connectivity Data, Colorado River, Grand Canyon
River-channel topography and sediment grain size on the Elwha River, Washington, 2006 to 2017
Watershed sediment yield following the 2018 Carr Fire, Whiskeytown National Recreation Area, northern California
Flooding duration and volume more important than peak discharge in explaining 18 years of gravel–cobble river change
Landscape evolution in eastern Chuckwalla Valley, Riverside County, California
Geomorphic and sedimentary effects of modern climate change: Current and anticipated future conditions in the western United States
Linking mesoscale meteorology with extreme landscape response: Effects of narrow cold frontal rainbands (NCFR)
Commentary: Variability in shelf sedimentation in response to fluvial sediment supply and coastal erosion over the past 1,000 Years in Monterey Bay, CA, United States
Case study: Thomas Fire
Refining the Baseline Sediment Budget for the Klamath River, California
Four dams in the Klamath River Hydroelectric Project (KHP) in Oregon and California (Figure 1) are currently scheduled to be removed over a period of a few weeks or months, beginning in January 2021. The Klamath dam removal will be the largest in the world by almost all measures, and is an unprecedented opportunity to advance science of river responses to such events. The KHP contains approximatel
Conceptualizing ecological responses to dam removal: If you remove it, what's to come?
Geomorphic evolution of a gravel‐bed river under sediment‐starved vs. sediment‐rich conditions: River response to the world's largest dam removal
Understanding river response to sediment pulses is a fundamental problem in geomorphic process studies, with myriad implications for river management. However, because large sediment pulses are rare and usually unanticipated, they are seldom studied at field scale. We examine fluvial response to a massive (~20 Mt) sediment pulse released by the largest dam removal globally, on the Elwha River, Was
A regime shift in sediment export from a coastal watershed during a record wet winter, California: Implications for landscape response to hydroclimatic extremes
Quantifying and forecasting changes in the areal extent of river valley sediment in response to altered hydrology and land cover
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
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River-channel topography, grain size, and turbidity records from the Carmel River, California, before, during, and after removal of San Clemente Dam (ver. 2.0, March 2022)
The San Clemente Dam, built in the 1920s on the Carmel River in Monterey County, California, was removed during 2014 and 2015. The dam-removal project was the largest in California to date, and one of the largest in the U.S. This USGS data release presents data collected before, during, and after the removal of the dam. The data were collected to study how the river channel's topographic profilesPolycyclic aromatic hydrocarbons (PAHs) and suspended sediment concentrations in the San Lorenzo River, Santa Cruz, California, USA
Water from the San Lorenzo River in Santa Cruz, California, was sampled to analyze for polycyclic aromatic hydrocarbons (PAHs) and suspended sediment concentrations (SSC) during the rainy seasons from 2008 to 2019 following drought conditions. The samples were collected using a US D-95 depth-integrated water sampler deployed from a bridge-box platform beneath a pedestrian bridge For each suspendeRain measurements in and near the CZU Lightning Complex Fire area, Santa Cruz Mountains, California, 2020 to 2021
The CZU Lightning Complex Fire (hereafter, "CZU Fire") ignited in the Santa Cruz Mountains, California, on August 16, 2020. By the time of full containment on September 22, 2020, the fire had burned 350 km2 (86,510 acres) in Santa Cruz and San Mateo Counties. The U.S. Geological Survey (USGS) installed four rain gages in and near the CZU Fire burn area to measure rainfall during the post-fire wetSediment grain-size data from the Klamath estuary, California
This data release includes grain-size measurements of sediment samples collected from the substrate surface and uppermost 10 cm of sediment deposits in the Klamath estuary, northern California. Samples were collected using a BMH-60 bed-material sampler deployed from a boat, or by hand trowel from subaerial or shallow-water (less than 0.5 m water depth) regions along the estuary margins and side chLuminescence, weather, and grain-size data from eastern Chuckwalla Valley, Riverside County, California
This data release contains luminescence, weather, and sediment grain-size data from eastern Chuckwalla Valley, Riverside County, California. This study investigates sedimentary and geomorphic processes in eastern Chuckwalla Valley, Riverside County, California, a region of arid, basin-and-range terrain where extensive solar-energy development is planned. The objectives were to (1) measure local weBathymetry, topography and orthomosaic imagery for Whiskeytown Lake, northern California (ver. 2.0, July 2021)
The Carr Fire ignited in northern California on July 23, 2018, and over the following six weeks burned almost 300,000 acres (approximately half on federal lands), resulting in a federal major-disaster declaration (DR-4382). Approximately 93 percent of the area within Whiskeytown National Recreation Area was burned extensively during the Carr Fire, including all of the landscape surrounding and draGrain-size data for sediment samples collected in Whiskeytown Lake, northern California, in 2018 and 2019
The Carr Fire ignited in northern California in July 2018, and ultimately burned almost 300,000 acres (approximately half on federal lands), resulting in a federal major-disaster declaration (DR-4382). Approximately 93% of the area within Whiskeytown National Recreation Area was burned extensively during the Carr Fire, including all of the landscape surrounding and draining into Whiskeytown Lake.Chirp sub-bottom data collected in 2019 in Whiskeytown Lake, California during USGS field activity 2018-686-FA
High-resolution chirp sub-bottom data were collected by the U.S. Geological Survey, Pacific Coastal and Marine Science Center in May of 2019 in Whiskeytown Lake, California using an Edgetech SB-512i sub-bottom profiler. These data were collected to measure possible debris flows into the lake during the 2018-2019 rainy season following the July-August 2018 Carr fire that burned vegetation around thField, geotechnical, and meteorological data of the 22 March 2018 narrow cold frontal rainband (NCFR) and its effects, Tuolumne River canyon, Sierra Nevada Foothills, California
This data release includes information used to support the manuscript "Linking mesoscale meteorology with extreme landscape response: effects of narrow cold frontal rainbands (NCFR)". The included datasets and supplement include information related to the 22 March 2018 NCFR and associated shallow landslides in the Toulumne Canyon triggered by this event. The three datasets and one supplemental infFloodplain data from the Hoh, Elwha, Queets, and Quinault Rivers in Olympic National Park, 1939-2013
Floodplain characteristics were quantified for four rivers in Olympic National Park, Washington, USA, using orthophoto imagery taken between 1939-2013.River Valley Sediment Connectivity Data, Colorado River, Grand Canyon
This workbook contains spatial data on the hydrology, sedimentology, and vegetation extent within the Colorado River corridor from 60 to 78 miles (97 to 125 kilometers) downstream from Glen Canyon Dam, Arizona. In combination with the accompanying MATLAB scripts, these data were used to generate the results within the accompanying manuscript (Kasprak et al., Quantifying and Forecasting Changes inRiver-channel topography and sediment grain size on the Elwha River, Washington, 2006 to 2017
The Elwha River, Washington, USA, was the site of the largest dam-removal project to date, in which two dams were removed between 2011 and 2014. Dam removal was made in stages over about a one-year period for the Elwha Dam (32 m high) and a three-year period for the Glines Canyon Dam (64 m high). This data release presents topographic and sediment grain size data collected by the U.S. Geological S - Maps
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Watershed sediment yield following the 2018 Carr Fire, Whiskeytown National Recreation Area, northern California
Wildfire risk has increased in recent decades over many regions, due to warming climate and other factors. Increased sediment export from recently burned landscapes can jeopardize downstream infrastructure and water resources, but physical landscape response to fire has not been quantified for some at-risk areas, including much of northern California, USA. We measured sediment yield from three watAuthorsAmy E. East, Joshua B. Logan, Peter Dartnell, Oren Lieber-Kotz, David B. Cavagnaro, Scott W. McCoy, Donald N. LindsayFlooding duration and volume more important than peak discharge in explaining 18 years of gravel–cobble river change
Floods play a critical role in geomorphic change, but whether peak magnitude, duration, volume, or frequency determines the resulting magnitude of erosion and deposition is a question often proposed in geomorphic effectiveness studies. This study investigated that question using digital elevation model differencing to compare and contrast three hydrologically distinct epochs of topographic changeAuthorsArielle Gervasi, Gregory Pasternack, Amy E. EastLandscape evolution in eastern Chuckwalla Valley, Riverside County, California
This study investigates sedimentary and geomorphic processes in eastern Chuckwalla Valley, Riverside County, California, a region of arid, basin-and-range terrain where extensive solar-energy development is planned. The objectives of this study were to (1) measure local weather parameters and use them to model aeolian sediment-transport potential; (2) identify surface sedimentary characteristics iAuthorsAmy E. East, Harrison J. Gray, Margaret Hiza Redsteer, Matthew BallmerGeomorphic and sedimentary effects of modern climate change: Current and anticipated future conditions in the western United States
Hydroclimatic changes associated with global warming over the past 50 years have been documented widely, but physical landscape responses are poorly understood thus far. Detecting sedimentary and geomorphic signals of modern climate change presents challenges owing to short record lengths, difficulty resolving signals in stochastic natural systems, influences of land use and tectonic activity, lonAuthorsAmy E. East, Joel B. SankeyLinking mesoscale meteorology with extreme landscape response: Effects of narrow cold frontal rainbands (NCFR)
Landscapes evolve in response to prolonged and/or intense precipitation resulting from atmospheric processes at various spatial and temporal scales. Whereas synoptic (large‐scale) features (e.g., atmospheric rivers and hurricanes) govern regional‐scale hydrologic hazards such as widespread flooding, mesoscale features such as thunderstorms or squall lines are more likely to trigger localized geomoAuthorsBrian D. Collins, N. S. Oakley, Jonathan P. Perkins, Amy E. East, Skye C. Corbett, Benjamin J. HatchettCommentary: Variability in shelf sedimentation in response to fluvial sediment supply and coastal erosion over the past 1,000 Years in Monterey Bay, CA, United States
A commentary on: Variability in Shelf Sedimentation in Response to Fluvial Sediment Supply and Coastal Erosion Over the Past 1,000 Years in Monterey Bay, CA, United States. by Carlin J., Addison J., Wagner A., Schwartz V., Hayward J., Severin V. (2019) Front. Earth Sci., 7:113. doi: 10.3389/feart.2019.00113AuthorsJonathan Warrick, Amy E. East, Curt D. Storlazzi, James E. ConradCase study: Thomas Fire
No abstract available.AuthorsJason R. Kreitler, Amy E. East, Joel B. Sankey, Christina (Naomi) TagueRefining the Baseline Sediment Budget for the Klamath River, California
Four dams in the Klamath River Hydroelectric Project (KHP) in Oregon and California (Figure 1) are currently scheduled to be removed over a period of a few weeks or months, beginning in January 2021. The Klamath dam removal will be the largest in the world by almost all measures, and is an unprecedented opportunity to advance science of river responses to such events. The KHP contains approximatel
AuthorsChauncey W. Anderson, Scott A. Wright, Liam N. Schenk, Katherine Skalak, Jennifer A. Curtis, Amy E. East, Adam BenthemConceptualizing ecological responses to dam removal: If you remove it, what's to come?
One of the desired outcomes of dam decommissioning and removal is the recovery of aquatic and riparian ecosystems. To investigate this common objective, we synthesized information from empirical studies and ecological theory into conceptual models that depict key physical and biological links driving ecological responses to removing dams. We define models for three distinct spatial domains: upstreAuthorsJ. Ryan Bellmore, George R. Pess, Jeffrey J. Duda, Jim E. O'Connor, Amy E. East, Melissa M. Foley, Andrew C. Wilcox, Jon J. Major, Patrick B. Shafroth, Sarah A. Morley, Christopher S. Magirl, Chauncey W. Anderson, James E. Evans, Christian E. Torgersen, Laura S. CraigByEcosystems Mission Area, Coastal and Marine Hazards and Resources Program, Species Management Research Program, Arizona Water Science Center, Forest and Rangeland Ecosystem Science Center, Fort Collins Science Center, Geology, Minerals, Energy, and Geophysics Science Center, John Wesley Powell Center for Analysis and Synthesis, Oregon Water Science Center, Pacific Coastal and Marine Science Center, Western Fisheries Research CenterGeomorphic evolution of a gravel‐bed river under sediment‐starved vs. sediment‐rich conditions: River response to the world's largest dam removal
Understanding river response to sediment pulses is a fundamental problem in geomorphic process studies, with myriad implications for river management. However, because large sediment pulses are rare and usually unanticipated, they are seldom studied at field scale. We examine fluvial response to a massive (~20 Mt) sediment pulse released by the largest dam removal globally, on the Elwha River, Was
AuthorsAmy E. East, Joshua B. Logan, Mark C. Mastin, Andrew C. Ritchie, Jennifer A. Bountry, Christopher S. Magirl, Joel B. SankeyA regime shift in sediment export from a coastal watershed during a record wet winter, California: Implications for landscape response to hydroclimatic extremes
Small, steep watersheds are prolific sediment sources from which sediment flux is highly sensitive to climatic changes. Storm intensity and frequency are widely expected to increase during the 21st century, and so assessing the response of small, steep watersheds to extreme rainfall is essential to understanding landscape response to climate change. During record winter rainfall in 2016–2017, theAuthorsAmy E. East, Andrew W. Stevens, Andrew C. Ritchie, Patrick L. Barnard, Pamela L. Campbell‐Swarzenski, Brian D. Collins, Christopher H. ConawayQuantifying and forecasting changes in the areal extent of river valley sediment in response to altered hydrology and land cover
In river valleys, sediment moves between active river channels, near-channel deposits including bars and floodplains, and upland environments such as terraces and aeolian dunefields. Sediment availability is a prerequisite for the sustained transfer of material between these areas, and for the eco-geomorphic functioning of river networks in general. However, the difficulty of monitoring sediment aAuthorsAlan Kasprak, Joel B. Sankey, Daniel Buscombe, Joshua Caster, Amy E. East, Paul E. GramsNon-USGS Publications**
East, Amy E; Harrison, Lee R; Smith, Douglas P; Logan, Joshua B; Bond, Rosealea M, Six years of fluvial response to a large dam removal on the Carmel River, California, USA: Earth surface processes and landforms : the journal of the British Geomorphological Research Group, 2023
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.
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