Joshua Caster
Joshua Caster is a Geographer with the USGS Southwest Biological Science Center (SBSC), and the Grand Canyon Monitoring and Research Center (GCMRC), in Flagstaff, Arizona.
Joshua has experience conducting scientific investigations across a wide range of disciplines, including hydrology, hydrogeology, archaeology, geoarchaeology, geomorphology, biogeomorphology, and quaternary geology. His research interests focus on understanding past, present, and future landscape alterations within dryland ecosystems resulting from the changing environment and human activity. His current work with the Grand Canyon Monitoring and Research Center supports a variety of environmental and cultural resource management efforts within Grand Canyon National Park and other federal lands throughout the southwestern United States. Much of this work incorporates field-based investigations with remote sensing technology, including light detection and ranging (lidar) instruments, airborne and drone-based photography, and satellite imagery, to quantify terrestrial surface processes. He uses these technologies to characterize bio-physical interactions at millimeter to multi-kilometer scales for refining our understanding of how and why dryland landscapes are changing and the role management actions can play in altering landscape evolution.
Professional Experience
2014 – Present: Geographer, U.S. Geological Survey
Education and Certifications
In Progress: Ph.D., Earth Systems, Northern Arizona University
2010: M.S., Physical Geography, University of North Texas
Science and Products
Filter Total Items: 19
Modern landscape processes affecting archaeological sites along the Colorado River corridor downstream of Glen Canyon Dam, Glen Canyon National Recreation Area, Arizona
The landscape of the Colorado River through Glen Canyon National Recreation Area formed over many thousands of years and was modified substantially after the completion of Glen Canyon Dam in 1963. Changes to river flow, sediment supply, channel base level, lateral extent of sedimentary terraces, and vegetation in the post-dam era have modified the river-corridor landscape and have altered the effe
Authors
Amy E. East, Joel B. Sankey, Helen C. Fairley, Joshua J. Caster, Alan Kasprak
Geomorphic process from topographic form: automating the interpretation of repeat survey data in river valleys
The ability to quantify the processes driving geomorphic change in river valley margins is vital to geomorphologists seeking to understand the relative role of transport mechanisms (e.g. fluvial, aeolian, and hillslope processes) in landscape dynamics. High-resolution, repeat topographic data are becoming readily available to geomorphologists. By contrasting digital elevation models derived from r
Authors
Alan Kasprak, Joshua J. Caster, Sara G. Bangen, Joel B. Sankey
Quantifying geomorphic change at ephemeral stream restoration sites using a coupled-model approach
Rock-detention structures are used as restoration treatments to engineer ephemeral stream channels of southeast Arizona, USA, to reduce streamflow velocity, limit erosion, retain sediment, and promote surface-water infiltration. Structures are intended to aggrade incised stream channels, yet little quantified evidence of efficacy is available. The goal of this 3-year study was to characterize the
Authors
Laura M. Norman, Joel B. Sankey, David Dean, Joshua J. Caster, Stephen B. DeLong, Whitney Henderson-DeLong, Jon D. Pelletier
Linking fluvial and aeolian morphodynamics in the Grand Canyon, USA
In river valleys, fluvial and upland landscapes are intrinsically linked through sediment exchange between the active channel, near-channel fluvial deposits, and higher elevation upland deposits. During floods, sediment is transferred from channels to low-elevation nearchannel deposits [Schmidt and Rubin, 1995]. Particularly in dryland river valleys, subsequent aeolian reworking of these flood dep
Authors
Alan Kasprak, Sara G. Bangen, Daniel Buscombe, Joshua Caster, Amy E. East, Paul E. Grams, Joel B. Sankey
Conditions and processes affecting sand resources at archeological sites in the Colorado River corridor below Glen Canyon Dam, Arizona
This study examined links among fluvial, aeolian, and hillslope geomorphic processes that affect archeological sites and surrounding landscapes in the Colorado River corridor downstream from Glen Canyon Dam, Arizona. We assessed the potential for Colorado River sediment to enhance the preservation of river-corridor archeological resources through aeolian sand deposition or mitigation of gully eros
Authors
Amy E. East, Brian D. Collins, Joel B. Sankey, Skye C. Corbett, Helen C. Fairley, Joshua J. Caster
Variability in rainfall at monitoring stations and derivation of a long-term rainfall intensity record in the Grand Canyon Region, Arizona, USA
In this study, we examine rainfall datasets of varying temporal length, resolution, and spatial distribution to characterize rainfall depth, intensity, and seasonality for monitoring stations along the Colorado River within Marble and Grand Canyons. We identify maximum separation distances between stations at which rainfall measurements might be most useful for inferring rainfall characteristics a
Authors
Joshua J. Caster, Joel B. Sankey
Gully annealing by fluvially-sourced Aeolian sand: remote sensing investigations of connectivity along the Fluvial-Aeolian-hillslope continuum on the Colorado River
Processes contributing to development of ephemeral gully channels are of great importance to landscapes worldwide, and particularly in dryland regions where soil loss and land degradation from gully erosion pose long-term, land-management problems. Whereas gully formation has been relatively well studied, much less is known of the processes that anneal gullies and impede their growth. This work in
Authors
Joel B. Sankey, Amy E. East, Brian D. Collins, Joshua J. Caster
Science and Products
Filter Total Items: 19
Modern landscape processes affecting archaeological sites along the Colorado River corridor downstream of Glen Canyon Dam, Glen Canyon National Recreation Area, Arizona
The landscape of the Colorado River through Glen Canyon National Recreation Area formed over many thousands of years and was modified substantially after the completion of Glen Canyon Dam in 1963. Changes to river flow, sediment supply, channel base level, lateral extent of sedimentary terraces, and vegetation in the post-dam era have modified the river-corridor landscape and have altered the effe
Authors
Amy E. East, Joel B. Sankey, Helen C. Fairley, Joshua J. Caster, Alan Kasprak
Geomorphic process from topographic form: automating the interpretation of repeat survey data in river valleys
The ability to quantify the processes driving geomorphic change in river valley margins is vital to geomorphologists seeking to understand the relative role of transport mechanisms (e.g. fluvial, aeolian, and hillslope processes) in landscape dynamics. High-resolution, repeat topographic data are becoming readily available to geomorphologists. By contrasting digital elevation models derived from r
Authors
Alan Kasprak, Joshua J. Caster, Sara G. Bangen, Joel B. Sankey
Quantifying geomorphic change at ephemeral stream restoration sites using a coupled-model approach
Rock-detention structures are used as restoration treatments to engineer ephemeral stream channels of southeast Arizona, USA, to reduce streamflow velocity, limit erosion, retain sediment, and promote surface-water infiltration. Structures are intended to aggrade incised stream channels, yet little quantified evidence of efficacy is available. The goal of this 3-year study was to characterize the
Authors
Laura M. Norman, Joel B. Sankey, David Dean, Joshua J. Caster, Stephen B. DeLong, Whitney Henderson-DeLong, Jon D. Pelletier
Linking fluvial and aeolian morphodynamics in the Grand Canyon, USA
In river valleys, fluvial and upland landscapes are intrinsically linked through sediment exchange between the active channel, near-channel fluvial deposits, and higher elevation upland deposits. During floods, sediment is transferred from channels to low-elevation nearchannel deposits [Schmidt and Rubin, 1995]. Particularly in dryland river valleys, subsequent aeolian reworking of these flood dep
Authors
Alan Kasprak, Sara G. Bangen, Daniel Buscombe, Joshua Caster, Amy E. East, Paul E. Grams, Joel B. Sankey
Conditions and processes affecting sand resources at archeological sites in the Colorado River corridor below Glen Canyon Dam, Arizona
This study examined links among fluvial, aeolian, and hillslope geomorphic processes that affect archeological sites and surrounding landscapes in the Colorado River corridor downstream from Glen Canyon Dam, Arizona. We assessed the potential for Colorado River sediment to enhance the preservation of river-corridor archeological resources through aeolian sand deposition or mitigation of gully eros
Authors
Amy E. East, Brian D. Collins, Joel B. Sankey, Skye C. Corbett, Helen C. Fairley, Joshua J. Caster
Variability in rainfall at monitoring stations and derivation of a long-term rainfall intensity record in the Grand Canyon Region, Arizona, USA
In this study, we examine rainfall datasets of varying temporal length, resolution, and spatial distribution to characterize rainfall depth, intensity, and seasonality for monitoring stations along the Colorado River within Marble and Grand Canyons. We identify maximum separation distances between stations at which rainfall measurements might be most useful for inferring rainfall characteristics a
Authors
Joshua J. Caster, Joel B. Sankey
Gully annealing by fluvially-sourced Aeolian sand: remote sensing investigations of connectivity along the Fluvial-Aeolian-hillslope continuum on the Colorado River
Processes contributing to development of ephemeral gully channels are of great importance to landscapes worldwide, and particularly in dryland regions where soil loss and land degradation from gully erosion pose long-term, land-management problems. Whereas gully formation has been relatively well studied, much less is known of the processes that anneal gullies and impede their growth. This work in
Authors
Joel B. Sankey, Amy E. East, Brian D. Collins, Joshua J. Caster