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 extends from Glen Canyon Dam at Lake Powell to Separation Canyon at Lake Mead, a total distance of approximately 255 river miles (410 river kilometer). Three other maps are based on imagery acquired in May 2002, 2009, and 2013, respectively, and are classifications of sand located above the wetted river channel (at river discharge of approximately 8,000 cubic feet per second, or 227 cubic meters per second) and below the approximate maximum contemporary flood stage of the river at a discharge of 45,000 cubic feet per second (1,274 cubic meters per second). Those three maps extend from Lees Ferry (approximately 15 miles downstream of Glen Canyon Dam) to Diamond Creek, a total distance of approximately 226 river miles (364 river kilometers). These three maps only have sand classified within large sand deposition zones (SDZs) in the river corridor. Sand transported by the Colorado River through Grand Canyon is stored on the river bed and in recirculation zones, or eddies, that typically house separation or reattachment sandbars in the lee of debris fans (Schmidt, 1990; Hazel et al., 2006). Alternatively, sand can also be found lining pools and channel margins upstream of debris fans (Schmidt, 1990). The SDZs were identified by delineating individual large eddies and adjacent debris fans, pools and channel margins which contain a majority of the areas of exposed unvegetated river-derived sand that can be classified by multispectral image analysis. The more comprehensive 2013 sand map extends outside of the SDZs and encompasses all river-derived sand within the entire width and length of the river corridor above the low-flow river stage. Each classification map was derived from a combination of unsupervised and supervised image classification methods followed by exhaustive image interpretation and map editing to identify river-derived sand that was not vegetated and not obviously colonized by biologic soil crust. The sand classifications have the same 0.2-meter ground resolution as the imagery. No formal accuracy assessment has been completed at this time for these data.

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 extends from Glen Canyon Dam at Lake Powell to Separation Canyon at Lake Mead, a total distance of approximately 255 river miles (410 river kilometer). Three other maps are based on imagery acquired in May 2002, 2009, and 2013, respectively, and are classifications of sand located above the wetted river channel (at river discharge of approximately 8,000 cubic feet per second, or 227 cubic meters per second) and below the approximate maximum contemporary flood stage of the river at a discharge of 45,000 cubic feet per second (1,274 cubic meters per second). Those three maps extend from Lees Ferry (approximately 15 miles downstream of Glen Canyon Dam) to Diamond Creek, a total distance of approximately 226 river miles (364 river kilometers). These three maps only have sand classified within large sand deposition zones (SDZs) in the river corridor. Sand transported by the Colorado River through Grand Canyon is stored on the river bed and in recirculation zones, or eddies, that typically house separation or reattachment sandbars in the lee of debris fans (Schmidt, 1990; Hazel et al., 2006). Alternatively, sand can also be found lining pools and channel margins upstream of debris fans (Schmidt, 1990). The SDZs were identified by delineating individual large eddies and adjacent debris fans, pools and channel margins which contain a majority of the areas of exposed unvegetated river-derived sand that can be classified by multispectral image analysis. The more comprehensive 2013 sand map extends outside of the SDZs and encompasses all river-derived sand within the entire width and length of the river corridor above the low-flow river stage. Each classification map was derived from a combination of unsupervised and supervised image classification methods followed by exhaustive image interpretation and map editing to identify river-derived sand that was not vegetated and not obviously colonized by biologic soil crust. The sand classifications have the same 0.2-meter ground resolution as the imagery. No formal accuracy assessment has been completed at this time for these data.

These data were compiled for assessing how geomorphic changes measured as topographic differences from repeat surveys represent measured and modelled estimates of aeolian sediment transport and dune mobility. Objective(s) of our study were to investigate whether topographic changes can serve as a proxy for aeolian transport and sediment mobility in dunefield environments. This was accomplished by relating topographic changes to modeled and observed estimates of sediment transport and dune mobility over months to decades within a partially vegetated dunefield starved of upwind sediment supplies. We specifically tested if topographic changes measured as net and total volume changes and topographic surface roughness differences provide evidence for intra-annual differences and decadal changes in sediment mobility for dune sand that is either currently bare, vegetated, or biocrust-covered. Lastly, these data were used as a framework for interpreting how aeolian transport and sediment mobility has changed for current land cover types over the preceding four decades. These data represent monthly topographic surveys and in-field sediment transport data collected between February 13, 2020 and December 16, 2020, piloted aerial imagery collected in 1984, 2002, 2009, 2013, and 2021, unoccupied aerial vehicle (UAV) imagery collected in March 2021, classification of land cover, and tabular summaries of topographic changes derived from these datasets. These data were collected between 1984 and 2021 within a small aeolian dunefield near the confluence of the Paria and Colorado Rivers, upstream of Grand Canyon National Park, Arizona. These data were collected by the U.S. Geological Survey. These data can be used to 1) to evaluate how dune surfaces with bare sand, sand with vegetated cover, and sand with biological soil crust cover (biocrust) change on a monthly time scale with differences in wind strength and 2) assess how the dunefield surface changed with vegetation loss and expansion over almost 4 decades. Additionally, these data could be used to assess detailed changes in landscape cover over monthly and decadal time scales.

These data were compiled for assessing how geomorphic changes measured as topographic differences from repeat surveys represent measured and modelled estimates of aeolian sediment transport and dune mobility. Objective(s) of our study were to investigate whether topographic changes can serve as a proxy for aeolian transport and sediment mobility in dunefield environments. This was accomplished by relating topographic changes to modeled and observed estimates of sediment transport and dune mobility over months to decades within a partially vegetated dunefield starved of upwind sediment supplies. We specifically tested if topographic changes measured as net and total volume changes and topographic surface roughness differences provide evidence for intra-annual differences and decadal changes in sediment mobility for dune sand that is either currently bare, vegetated, or biocrust-covered. Lastly, these data were used as a framework for interpreting how aeolian transport and sediment mobility has changed for current land cover types over the preceding four decades. These data represent monthly topographic surveys and in-field sediment transport data collected between February 13, 2020 and December 16, 2020, piloted aerial imagery collected in 1984, 2002, 2009, 2013, and 2021, unoccupied aerial vehicle (UAV) imagery collected in March 2021, classification of land cover, and tabular summaries of topographic changes derived from these datasets. These data were collected between 1984 and 2021 within a small aeolian dunefield near the confluence of the Paria and Colorado Rivers, upstream of Grand Canyon National Park, Arizona. These data were collected by the U.S. Geological Survey. These data can be used to 1) to evaluate how dune surfaces with bare sand, sand with vegetated cover, and sand with biological soil crust cover (biocrust) change on a monthly time scale with differences in wind strength and 2) assess how the dunefield surface changed with vegetation loss and expansion over almost 4 decades. Additionally, these data could be used to assess detailed changes in landscape cover over monthly and decadal time scales.

These data were compiled for assessing how geomorphic changes measured as topographic differences from repeat surveys represent measured and modelled estimates of aeolian sediment transport and dune mobility. Objective(s) of our study were to investigate whether topographic changes can serve as a proxy for aeolian transport and sediment mobility in dunefield environments. This was accomplished by relating topographic changes to modeled and observed estimates of sediment transport and dune mobility over months to decades within a partially vegetated dunefield starved of upwind sediment supplies. We specifically tested if topographic changes measured as net and total volume changes and topographic surface roughness differences provide evidence for intra-annual differences and decadal changes in sediment mobility for dune sand that is either currently bare, vegetated, or biocrust-covered. Lastly, these data were used as a framework for interpreting how aeolian transport and sediment mobility has changed for current land cover types over the preceding four decades. These data represent monthly topographic surveys and in-field sediment transport data collected between February 13, 2020 and December 16, 2020, piloted aerial imagery collected in 1984, 2002, 2009, 2013, and 2021, unoccupied aerial vehicle (UAV) imagery collected in March 2021, classification of land cover, and tabular summaries of topographic changes derived from these datasets. These data were collected between 1984 and 2021 within a small aeolian dunefield near the confluence of the Paria and Colorado Rivers, upstream of Grand Canyon National Park, Arizona. These data were collected by the U.S. Geological Survey. These data can be used to 1) to evaluate how dune surfaces with bare sand, sand with vegetated cover, and sand with biological soil crust cover (biocrust) change on a monthly time scale with differences in wind strength and 2) assess how the dunefield surface changed with vegetation loss and expansion over almost 4 decades. Additionally, these data could be used to assess detailed changes in landscape cover over monthly and decadal time scales.

These data were compiled for assessing how geomorphic changes measured as topographic differences from repeat surveys represent measured and modelled estimates of aeolian sediment transport and dune mobility. Objective(s) of our study were to investigate whether topographic changes can serve as a proxy for aeolian transport and sediment mobility in dunefield environments. This was accomplished by relating topographic changes to modeled and observed estimates of sediment transport and dune mobility over months to decades within a partially vegetated dunefield starved of upwind sediment supplies. We specifically tested if topographic changes measured as net and total volume changes and topographic surface roughness differences provide evidence for intra-annual differences and decadal changes in sediment mobility for dune sand that is either currently bare, vegetated, or biocrust-covered. Lastly, these data were used as a framework for interpreting how aeolian transport and sediment mobility has changed for current land cover types over the preceding four decades. These data represent monthly topographic surveys and in-field sediment transport data collected between February 13, 2020 and December 16, 2020, piloted aerial imagery collected in 1984, 2002, 2009, 2013, and 2021, unoccupied aerial vehicle (UAV) imagery collected in March 2021, classification of land cover, and tabular summaries of topographic changes derived from these datasets. These data were collected between 1984 and 2021 within a small aeolian dunefield near the confluence of the Paria and Colorado Rivers, upstream of Grand Canyon National Park, Arizona. These data were collected by the U.S. Geological Survey. These data can be used to 1) to evaluate how dune surfaces with bare sand, sand with vegetated cover, and sand with biological soil crust cover (biocrust) change on a monthly time scale with differences in wind strength and 2) assess how the dunefield surface changed with vegetation loss and expansion over almost 4 decades. Additionally, these data could be used to assess detailed changes in landscape cover over monthly and decadal time scales.

These data were compiled for assessing how geomorphic changes measured as topographic differences from repeat surveys represent measured and modelled estimates of aeolian sediment transport and dune mobility. Objective(s) of our study were to investigate whether topographic changes can serve as a proxy for aeolian transport and sediment mobility in dunefield environments. This was accomplished by relating topographic changes to modeled and observed estimates of sediment transport and dune mobility over months to decades within a partially vegetated dunefield starved of upwind sediment supplies. We specifically tested if topographic changes measured as net and total volume changes and topographic surface roughness differences provide evidence for intra-annual differences and decadal changes in sediment mobility for dune sand that is either currently bare, vegetated, or biocrust-covered. Lastly, these data were used as a framework for interpreting how aeolian transport and sediment mobility has changed for current land cover types over the preceding four decades. These data represent monthly topographic surveys and in-field sediment transport data collected between February 13, 2020 and December 16, 2020, piloted aerial imagery collected in 1984, 2002, 2009, 2013, and 2021, unoccupied aerial vehicle (UAV) imagery collected in March 2021, classification of land cover, and tabular summaries of topographic changes derived from these datasets. These data were collected between 1984 and 2021 within a small aeolian dunefield near the confluence of the Paria and Colorado Rivers, upstream of Grand Canyon National Park, Arizona. These data were collected by the U.S. Geological Survey. These data can be used to 1) to evaluate how dune surfaces with bare sand, sand with vegetated cover, and sand with biological soil crust cover (biocrust) change on a monthly time scale with differences in wind strength and 2) assess how the dunefield surface changed with vegetation loss and expansion over almost 4 decades. Additionally, these data could be used to assess detailed changes in landscape cover over monthly and decadal time scales.

These data were compiled for assessing how geomorphic changes measured as topographic differences from repeat surveys represent measured and modelled estimates of aeolian sediment transport and dune mobility. Objective(s) of our study were to investigate whether topographic changes can serve as a proxy for aeolian transport and sediment mobility in dunefield environments. This was accomplished by relating topographic changes to modeled and observed estimates of sediment transport and dune mobility over months to decades within a partially vegetated dunefield starved of upwind sediment supplies. We specifically tested if topographic changes measured as net and total volume changes and topographic surface roughness differences provide evidence for intra-annual differences and decadal changes in sediment mobility for dune sand that is either currently bare, vegetated, or biocrust-covered. Lastly, these data were used as a framework for interpreting how aeolian transport and sediment mobility has changed for current land cover types over the preceding four decades. These data represent monthly topographic surveys and in-field sediment transport data collected between February 13, 2020 and December 16, 2020, piloted aerial imagery collected in 1984, 2002, 2009, 2013, and 2021, unoccupied aerial vehicle (UAV) imagery collected in March 2021, classification of land cover, and tabular summaries of topographic changes derived from these datasets. These data were collected between 1984 and 2021 within a small aeolian dunefield near the confluence of the Paria and Colorado Rivers, upstream of Grand Canyon National Park, Arizona. These data were collected by the U.S. Geological Survey. These data can be used to 1) to evaluate how dune surfaces with bare sand, sand with vegetated cover, and sand with biological soil crust cover (biocrust) change on a monthly time scale with differences in wind strength and 2) assess how the dunefield surface changed with vegetation loss and expansion over almost 4 decades. Additionally, these data could be used to assess detailed changes in landscape cover over monthly and decadal time scales.

Grand Falls dune field (GFDF) is located on the Navajo Nation, ~70 km NE of Flagstaff, AZ. This active dune field displays a range of morphologies, including barchans, smaller dunes, and ripples, and is bimodal in composition. The felsic component is likely derived from the Little Colorado River, and the mafic component (basaltic grains) is locally sourced from nearby cinder cones [1]. GFDF is an excellent analog site for both active dunes on Mars and other planetary bodies that have dune-like features (e.g., Venus and Titan). We have set up a meteorological station within the dune field that records temperature, barometric pressure, relative humidity, wind direction, wind speed, solar radiation, and precipitation. In addition, an array of temperature and relative humidity sensors were deployed at five different depths within the soil to capture diurnal temperatures and humidity variations. This array is located near the meteorological station and both sets of instruments collect data every 15 minutes. A set of cameras have been positioned near an active ripple field, ~7 m southeast of the meteorological station. The cameras take images every 10 minutes to monitor ripple movement. A series of images were also taken using a NIKON D250 camera, in which data were then processed using the software Agisoft Metashope Professional to create a digital elevation model of the ripple field. [1] Hayward, R. K. et al. (2010) 2nd Int. Plan. Dunes Wrkshp., Abstract #2004.

Grand Falls dune field (GFDF) is located on the Navajo Nation, ~70 km NE of Flagstaff, AZ. This active dune field displays a range of morphologies, including barchans, smaller dunes, and ripples, and is bimodal in composition. The felsic component is likely derived from the Little Colorado River, and the mafic component (basaltic grains) is locally sourced from nearby cinder cones [1]. GFDF is an excellent analog site for both active dunes on Mars and other planetary bodies that have dune-like features (e.g., Venus and Titan). We have set up a meteorological station within the dune field that records temperature, barometric pressure, relative humidity, wind direction, wind speed, solar radiation, and precipitation. In addition, an array of temperature and relative humidity sensors were deployed at five different depths within the soil to capture diurnal temperatures and humidity variations. This array is located near the meteorological station and both sets of instruments collect data every 15 minutes. A set of cameras have been positioned near an active ripple field, ~7 m southeast of the meteorological station. The cameras take images every 10 minutes to monitor ripple movement. A series of images were also taken using a NIKON D250 camera, in which data were then processed using the software Agisoft Metashope Professional to create a digital elevation model of the ripple field. [1] Hayward, R. K. et al. (2010) 2nd Int. Plan. Dunes Wrkshp., Abstract #2004.