A high-resolution image collection in 2021 will be the most recent in a rich archive of aerial imagery that is used to track changes of the Colorado River in the Grand Canyon. Imagery will be acquired from an airplane in Grand Canyon National Park along the Colorado River corridor and the Little Colorado River starting Memorial Day weekend and continuing through the first week of June 2021. This imagery will be used by the USGS and partners from the Glen Canyon Dam Adaptive Management Program (GCDAMP) to monitor changes in the Colorado River and riparian ecosystem in Grand Canyon and impacts of management including Glen Canyon Dam operations. Water released from Glen Canyon Dam will be reduced to a steady discharge of 8,000 cubic feet per second (cfs) in the Colorado River for the duration of the image collection mission. The low river discharge is required because consistent water levels are necessary for remote sensing image analyses that compare this new image dataset to historic datasets which also were collected with a constant steady discharge of 8,000 cfs.
History of Aerial Remote Sensing in Grand Canyon
Similar to 2021, 4-band multispectral imagery and photogrammetrically derived topography data were also previously acquired in 2002, 2005, 2009, and 2013. With each of those previous digital image acquisitions, GCMRC remote sensing staff developed and improved upon a methodology for producing a spatially seamless, spectrally consistent, and nearly cloud- and blemish-free image mosaic (Davis and others, 2012; Durning and others, 2016). That proven methodology will be used to develop an image mosaic from the 2021 acquisition.
An abbreviated history of aerial remote sensing of the Colorado River in Grand Canyon:
- The earliest air photos are black and white prints acquired from an airplane in 1935.
- The first set of air photos acquired after Glen Canyon Dam was completed are black and white prints from May 1965
- The first color and color-infrared air photos were acquired during flights in the 1980s
- The first digital multispectral images were acquired in the late-1990s
- The first acquisition similar to this year's overflight (high spatial resolution digital multispectral imagery and digital topography) occurred in May 2002, and then again in 2004, 2005, 2009, 2013, 2021
Aerial Remote Sensing Science for the Colorado River in Grand Canyon
GCMRC scientists have leveraged this rich archive of data to relate observations of landcover changes to physical, biological and hydrological processes (Figure 1). This remote sensing science helps to support resource management decisions in the iconic Grand Canyon and Colorado River. One example is a quantitative assessment of riparian vegetation changes that occurred as a function of dam operations and climate during the first five decades of the operations of Glen Canyon Dam. Other examples are mapping tamarisk and tamarisk beetle impacts throughout the Colorado River in Glen Canyon and Grand Canyon. For these tamarisk studies, imagery were incorporated from the Worldview 2 constellation satellite and, while the satellite imagery were helpful, they were not high resolution enough to replace the airborne multispectral imagery such as will be collected in the 2021 overflight. Changes in campsites area used by river runners and dunefields sourced by windblown river sand, which help to preserve archeological sites, are also evaluated with remote sensing. Using highly detailed vegetation and sand maps and predictive modelling, future riparian landcover changes are forecasted as a function of river flows owing to the planned operations of Glen Canyon Dam through 2036.
Below are other science projects associated with this project.
Geospatial Science and Technology
River Campsites in Grand Canyon National Park
Geospatial Science and Technology
Overview of Riparian Vegetation in Grand Canyon
Connectivity of Sand Resources Along the Colorado River in Grand Canyon
Riparian Remote Sensing in the Colorado River and Grand Canyon Region
Below are data or web applications associated with this project.
Four Band Image Mosaic of the Colorado River Corridor in Arizona2013, including Accuracy Assessment Data
Northern tamarisk beetle impact and classification maps, Grand Canyon National Park, Arizona
Colorado River Mile System, Grand Canyon, Arizona
Riparian species vegetation classification data for the Colorado River within Grand Canyon derived from 2013 airborne imagery
River Valley Sediment Connectivity Data, Colorado River, Grand Canyon
Sand classifications along the Colorado River in Grand Canyon derived from 2002, 2009, and 2013 high-resolution multispectral airborne imagery
Four Band Image Mosaic of the Colorado River Corridor in Arizona2013, including Accuracy Assessment Data
Riparian vegetation, Colorado River, and climate: five decades of spatio-temporal dynamics in the Grand Canyon with river regulation
Below are publications associated with this project.
Riparian vegetation, Colorado River, and climate: five decades of spatiotemporal dynamics in the Grand Canyon with river regulation
Hydrologic and geomorphic effects on riparian plant species occurrence and encroachment: Remote sensing of 360 km of the Colorado River in Grand Canyon
Monitoring Tamarix changes using WorldView-2 satellite imagery in Grand Canyon National Park, Arizona
Future regulated flows of the Colorado River in Grand Canyon foretell decreased areal extent of sediment and increases in riparian vegetation
Associations between riparian plant morphological guilds and fluvial sediment dynamics along the regulated Colorado River in Grand Canyon
The effects of topographic surveying technique and data resolution on the detection and interpretation of geomorphic change
Quantifying and forecasting changes in the areal extent of river valley sediment in response to altered hydrology and land cover
Quantifying geomorphic and vegetation change at sandbar campsites in response to flow regulation and controlled floods, Grand Canyon National Park, Arizona
The response of source-bordering aeolian dunefields to sediment-supply changes 1: Effects of wind variability and river-valley morphodynamics
The response of source-bordering aeolian dunefields to sediment-supply changes 2: Controlled floods of the Colorado River in Grand Canyon, Arizona, USA
Geomorphic process from topographic form: automating the interpretation of repeat survey data in river valleys
Four-band image mosaic of the Colorado River corridor downstream of Glen Canyon Dam in Arizona, derived from the May 2013 airborne image acquisition
Remote sensing of tamarisk biomass, insect herbivory, and defoliation: Novel methods in the Grand Canyon Region, Arizona
- Overview
A high-resolution image collection in 2021 will be the most recent in a rich archive of aerial imagery that is used to track changes of the Colorado River in the Grand Canyon. Imagery will be acquired from an airplane in Grand Canyon National Park along the Colorado River corridor and the Little Colorado River starting Memorial Day weekend and continuing through the first week of June 2021. This imagery will be used by the USGS and partners from the Glen Canyon Dam Adaptive Management Program (GCDAMP) to monitor changes in the Colorado River and riparian ecosystem in Grand Canyon and impacts of management including Glen Canyon Dam operations. Water released from Glen Canyon Dam will be reduced to a steady discharge of 8,000 cubic feet per second (cfs) in the Colorado River for the duration of the image collection mission. The low river discharge is required because consistent water levels are necessary for remote sensing image analyses that compare this new image dataset to historic datasets which also were collected with a constant steady discharge of 8,000 cfs.
History of Aerial Remote Sensing in Grand Canyon
Similar to 2021, 4-band multispectral imagery and photogrammetrically derived topography data were also previously acquired in 2002, 2005, 2009, and 2013. With each of those previous digital image acquisitions, GCMRC remote sensing staff developed and improved upon a methodology for producing a spatially seamless, spectrally consistent, and nearly cloud- and blemish-free image mosaic (Davis and others, 2012; Durning and others, 2016). That proven methodology will be used to develop an image mosaic from the 2021 acquisition.
An abbreviated history of aerial remote sensing of the Colorado River in Grand Canyon:
- The earliest air photos are black and white prints acquired from an airplane in 1935.
- The first set of air photos acquired after Glen Canyon Dam was completed are black and white prints from May 1965
- The first color and color-infrared air photos were acquired during flights in the 1980s
- The first digital multispectral images were acquired in the late-1990s
- The first acquisition similar to this year's overflight (high spatial resolution digital multispectral imagery and digital topography) occurred in May 2002, and then again in 2004, 2005, 2009, 2013, 2021
Aerial Remote Sensing Science for the Colorado River in Grand Canyon
GCMRC scientists have leveraged this rich archive of data to relate observations of landcover changes to physical, biological and hydrological processes (Figure 1). This remote sensing science helps to support resource management decisions in the iconic Grand Canyon and Colorado River. One example is a quantitative assessment of riparian vegetation changes that occurred as a function of dam operations and climate during the first five decades of the operations of Glen Canyon Dam. Other examples are mapping tamarisk and tamarisk beetle impacts throughout the Colorado River in Glen Canyon and Grand Canyon. For these tamarisk studies, imagery were incorporated from the Worldview 2 constellation satellite and, while the satellite imagery were helpful, they were not high resolution enough to replace the airborne multispectral imagery such as will be collected in the 2021 overflight. Changes in campsites area used by river runners and dunefields sourced by windblown river sand, which help to preserve archeological sites, are also evaluated with remote sensing. Using highly detailed vegetation and sand maps and predictive modelling, future riparian landcover changes are forecasted as a function of river flows owing to the planned operations of Glen Canyon Dam through 2036.
Example graph of land cover calculations derived from remote sensing airborne image analysis for 0.1-mile segments of the Colorado River from Glen Canyon Dam to Diamond Creek. The percentage of the river valley covered by water (at 8,000 CFS river discharge), sand, vegetation, and other landcover are plotted for each 0.1-mile segment of the river. - Science
Below are other science projects associated with this project.
Geospatial Science and Technology
The U.S. Geological Survey’s Southwest Biological Science Center, and more specifically, its River Ecosystem Science branch which includes the Grand Canyon Monitoring and Research Center (GCMRC), is a preeminent science group that has more than 20 years of experience of providing high-quality, detailed science to resource managers and stakeholders primarily concerned with the effects of dam...River Campsites in Grand Canyon National Park
Sandbars have been used as campsites by river runners and hikers since the first expeditions to the region more than 100 years ago. Sandbar campsites continue to be an important part of the recreational experience for the more than 25,000 hikers and river runners that visit the Colorado River corridor each year. Because the Colorado River is dominated by bedrock cliffs and steep talus slopes...Geospatial Science and Technology
The U.S. Geological Survey’s Southwest Biological Science Center, and more specifically, its River Ecosystem Science branch which includes the Grand Canyon Monitoring and Research Center (GCMRC), is a preeminent science group that has more than 20 years of experience of providing high-quality, detailed science to resource managers and stakeholders primarily concerned with the effects of dam...Overview of Riparian Vegetation in Grand Canyon
Riparian areas are conspicuous belts of dense, green vegetation along streams and rivers, and can be considered “ribbons of life”. Despite covering less than 2 percent of the land area in the southwestern U.S., riparian areas tend to have high species diversity and population density, making them valuable to managers, scientists, and the public. These unique ecosystems act as a link between dry...Connectivity of Sand Resources Along the Colorado River in Grand Canyon
We study the links among different geomorphic processes that affect river valley landscapes in the Colorado River downstream from Glen Canyon Dam, Arizona. Dam-released flows affect the deposition and retention of sandbars that serve as sources for other sand resources, such as windblown sand dunes, throughout the Colorado River ecosystem. The degree to which the landscapes are differentially...Riparian Remote Sensing in the Colorado River and Grand Canyon Region
Riparian vegetation has increased dramatically along the Colorado River downstream of Glen Canyon Dam since the closure of the dam in 1963. The spatial patterns and temporal rates of vegetation increase occur due to changes in river hydrology, dam operations, and climate. The increase in vegetation, particularly onto otherwise bare sandbars, has impacted recreational, geomorphological, biological... - Data
Below are data or web applications associated with this project.
Four Band Image Mosaic of the Colorado River Corridor in Arizona2013, including Accuracy Assessment Data
In May 2013, the Grand Canyon Monitoring and Research Center (GCMRC) of the U.S. Geological Surveys (USGS) Southwest Biological Science Center (SBSC) acquired airborne multispectral high resolution data for the Colorado River in Grand Canyon in Arizona, USA. The imagery data consist of four bands (blue, green, red and near infrared) with a ground resolution of 20 centimeters (cm). These data are aNorthern tamarisk beetle impact and classification maps, Grand Canyon National Park, Arizona
These data are satellite image-derived, classification maps of tamarisk (Tamarisk spp.) along the Colorado River in Grand Canyon National Park from river km 315 to 363, approximately from Parashant Canyon to Diamond Creek tributaries. The classification maps are published in TIF raster format. Two maps are published: 1) a classification of healthy, defoliated, and tamarisk canopy dieback from theColorado River Mile System, Grand Canyon, Arizona
These data represent the centerline and measured increments at hundredths, tenths and whole miles, along the centerline of the Colorado River beginning at Glen Canyon Dam near Page, Arizona and terminating near the inflow s of Lake Mead in the Grand Canyon region of Arizona, USA. The centerline was digitized using Color Infra-Red (CIR) orthophotography collected in March 2000 as source informatioRiparian species vegetation classification data for the Colorado River within Grand Canyon derived from 2013 airborne imagery
These data are a species-level classification map of riparian vegetation in the Colorado River riparian corridor in Grand Canyon, Arizona, USA. The classification is derived from 0.2 m pixel resolution multispectral aerial imagery acquired in May 2013. The classification spans the riparian zone of the river corridor between Glen Canyon Dam near Page, Arizona, and Lake Mead at Pearce Ferry, ArizonaRiver 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 inSand classifications along the Colorado River in Grand Canyon derived from 2002, 2009, and 2013 high-resolution multispectral airborne imagery
These data are remote sensing image-based classification maps of unvegetated river-derived sand along the Colorado River. One map is based on imagery acquired in May 2013 and is a classification of sand located above the wetted river channel in the imagery which was acquired at the approximate contemporary low-flow river discharge of 8,000 cubic feet per second (227 cubic meters per second) and exFour Band Image Mosaic of the Colorado River Corridor in Arizona2013, including Accuracy Assessment Data
In May 2013, the Grand Canyon Monitoring and Research Center (GCMRC) of the U.S. Geological Surveys (USGS) Southwest Biological Science Center (SBSC) acquired airborne multispectral high resolution data for the Colorado River in Grand Canyon in Arizona, USA. The imagery data consist of four bands (blue, green, red and near infrared) with a ground resolution of 20 centimeters (cm). These data are aRiparian vegetation, Colorado River, and climate: five decades of spatio-temporal dynamics in the Grand Canyon with river regulation
These data include image-based classifications of total vegetation from 1965, 1973, 1984, 1992, 2002, 2004, 2005, and 2009, and characteristics of the river channel along the riparian area of the Colorado River between Glen Canyon Dam and Lake Mead Reservoir. Also, these polygon data represent the area inundated by the Colorado River in the aerial imagery from overflight of the Grand Canyon in May - Publications
Below are publications associated with this project.
Riparian vegetation, Colorado River, and climate: five decades of spatiotemporal dynamics in the Grand Canyon with river regulation
Documentation of the interacting effects of river regulation and climate on riparian vegetation has typically been limited to small segments of rivers or focused on individual plant species. We examine spatiotemporal variability in riparian vegetation for the Colorado River in Grand Canyon relative to river regulation and climate, over the five decades since completion of the upstream Glen CanyonAuthorsJoel B. Sankey, Barbara E. Ralston, Paul E. Grams, John C. Schmidt, Laura E. CagneyFilter Total Items: 15Hydrologic and geomorphic effects on riparian plant species occurrence and encroachment: Remote sensing of 360 km of the Colorado River in Grand Canyon
A common impact on riparian ecosystem function following river regulation is the expansion and encroachment of riparian plant species in the active river channels and floodplain, which reduces flow of water and suspended sediment between the river, riparian area, and upland ecosystems. We characterized riparian plant species occurrence and quantified encroachment within the dam-regulated ColoradoAuthorsLaura E. Durning, Joel B. Sankey, Charles Yackulic, Paul Grams, Bradley J. Butterfield, Temuulen T. SankeyMonitoring Tamarix changes using WorldView-2 satellite imagery in Grand Canyon National Park, Arizona
Remote sensing methods are commonly used to monitor the invasive riparian shrub tamarisk (Tamarix spp.) and its response to the northern tamarisk beetle (D. carinulata), a specialized herbivore introduced as a biocontrol agent to control tamarisk in the Southwest USA in 2001. We use a Spectral Angle Mapper (SAM) supervised classification method with WorldView-2 (2 m spatial resolution) multispectrAuthorsNathaniel D. Bransky, Temuulen T. Sankey, Joel B. Sankey, Matthew D. Johnson, Levi R. JamisonFuture regulated flows of the Colorado River in Grand Canyon foretell decreased areal extent of sediment and increases in riparian vegetation
Sediment transfer, or connectivity, by aeolian processes between channel-proximal and upland deposits in river valleys is important for the maintenance of river corridor biophysical characteristics. In regulated river systems, dams control the magnitude and duration of discharge. Alterations to the flow regime driven by dams that increase the inundation duration of sediment, or which drive the encAuthorsAlan Kasprak, Joel B. Sankey, Bradley J. ButterfieldAssociations between riparian plant morphological guilds and fluvial sediment dynamics along the regulated Colorado River in Grand Canyon
Effects of riparian vegetation on fluvial sediment dynamics depend on morphological traits of the constituent species. Determining the effects of different morphological guilds on sedimentation rates, as influenced by multiple aspects of dam operations, can help identify viable strategies for streamflow and vegetation management to achieve riparian resource goals. Plants of increasing size and braAuthorsBradley J. Butterfield, Paul Grams, Laura E. Durning, Joseph Hazel, Emily C. Palmquist, Barbara Ralston, Joel B. SankeyThe effects of topographic surveying technique and data resolution on the detection and interpretation of geomorphic change
Change detection of high resolution topographic data is commonly used in river valleys to quantify reach- and site-scale sediment budgets by estimating the erosion/deposition volume, and to interpret the geomorphic processes driving erosion and deposition. Field survey data are typically collected as point clouds that are often converted to gridded raster datasets and the ultimate choice of grid rAuthorsAlan Kasprak, Nathaniel D. Bransky, Joel B. Sankey, Joshua Caster, Temulen T. SankeyQuantifying 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. GramsQuantifying geomorphic and vegetation change at sandbar campsites in response to flow regulation and controlled floods, Grand Canyon National Park, Arizona
Sandbars along the Colorado River in Grand Canyon National Park, USA, are an important recreational resource used as campsites by over 25,000 river runners and hikers annually. The number and size of campsites decreased following the completion of Glen Canyon Dam in 1963 due to reductions of sediment that replenish sandbars and increases in vegetation cover caused by flow regulation. Campsite areaAuthorsDaniel R. Hadley, Paul E. Grams, Matthew A. KaplinskiThe response of source-bordering aeolian dunefields to sediment-supply changes 1: Effects of wind variability and river-valley morphodynamics
Source-bordering dunefields (SBDs), which are primarily built and maintained with river-derived sediment, are found in many large river valleys and are currently impacted by changes in sediment supply due to climate change, land use changes, and river regulation. Despite their importance, a physically based, applied approach for quantifying the response of SBDs to changes in sediment supply does nAuthorsJoel B. Sankey, Alan Kasprak, Joshua Caster, Amy E. East, Helen C. FairleyThe response of source-bordering aeolian dunefields to sediment-supply changes 2: Controlled floods of the Colorado River in Grand Canyon, Arizona, USA
In the Colorado River downstream of Glen Canyon Dam in the Grand Canyon, USA, controlled floods are used to resupply sediment to, and rebuild, river sandbars that have eroded severely over the past five decades owing to dam-induced changes in river flow and sediment supply. In this study, we examine whether controlled floods, can in turn resupply aeolian sediment to some of the large source-borderAuthorsJoel B. Sankey, Joshua Caster, Alan Kasprak, Amy E. EastGeomorphic 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 rAuthorsAlan Kasprak, Joshua J. Caster, Sara G. Bangen, Joel B. SankeyFour-band image mosaic of the Colorado River corridor downstream of Glen Canyon Dam in Arizona, derived from the May 2013 airborne image acquisition
In May 2013, the U.S. Geological Survey’s Grand Canyon Monitoring and Research Center acquired airborne multispectral high-resolution data for the Colorado River in the Grand Canyon, Arizona. The image data, which consist of four color bands (blue, green, red, and near-infrared) with a ground resolution of 20 centimeters, are available to the public as 16-bit geotiff files at http://dx.doi.org/10.AuthorsLaura E. Durning, Joel B. Sankey, Philip A. Davis, Temuulen T. SankeyRemote sensing of tamarisk biomass, insect herbivory, and defoliation: Novel methods in the Grand Canyon Region, Arizona
Tamarisk is an invasive, riparian shrub species in the southwestern USA. The northern tamarisk beetle (Diorhabda carinulata) has been introduced to several states to control tamarisk. We classified tamarisk distribution in the Glen Canyon National Recreation Area, Arizona using a 0.2 m resolution, airborne multispectral data and estimated tamarisk beetle effects (overall accuracy of 86 percent) leAuthorsTemuulen T. Sankey, Joel B. Sankey, Rene Horne, Ashton Bedford - Partners