Richard L Reynolds
I investigate how climatic variability, weather, and land uses affect surfaces and ecosystems of deserts, with emphasis on sediment eroded, transported, and deposited by wind, mostly as atmospheric dust.
My studies probe the geologic, biologic, and human controls on dust generation as well as the mineralogic and geochemical properties of dust that in turn affect climate, weather, ecosystem health, water resources (effects of dust on melting of snow and ice), ocean fertility, and the health of a large proportion of earth’s people. I have also conducted research on:
- Hawaiian coral-reef health in settings of coastal erosion
- Quaternary climate and responses of landscapes to climatic change and human activities
- Iron-sulfur diagenesis and its effects on lake-sediment paleoenvironmental records
- Magnetic and chemical records of airborne pollution and environmental change
- Paleomagnetism of Tertiary and Quaternary sedimentary and igneous rocks
- Sources of magnetic anomalies in the shallow crust
- Field geology, Antarctica (1970-1971; 1978-1979)
Professional Experience
Research Geologist, USGS (periodic supervisory positions) 1975-2012
Acting Program Manager, Global Change Program USGS 2002
Senior Scientist, USGS 2012-2013 Emeritus since 2013
Adjunct Research Professor, Univ. of Minnesota
Affiliate, Institute for Arctic and Alpine Research Univ. of Colorado
Education and Certifications
Ph.D., Univ. of Colorado, 1975
M.S., Univ. of Colorado, 1970
A.B., Princeton University, 1968
Affiliations and Memberships*
Geological Society of America; Fellow
American Geophysical Union. Assoc. Editor, Jour. Geophysical Res. 1992-1995
Yellowstone-Bighorn Research Assoc.
American Quaternary Assoc.
International Medical Geology Assoc.
International Society for Aeolian Research (guest editor, 2013-14; Board of Directors, 2014-2016)
Honors and Awards
2012 Elected Senior Scientist, USGS
2012-2014 Distinguished Visiting Scholar, School of Geography and the Environment, Univ. of Oxford
2011 Astor Visiting Lecturer for the Humanities, Univ. of Oxford
2007 Co-recipient, Kirk Bryan Award; best publication in Quaternary Geology and Geomorphology, Geological Society of America
Meritorious Service Award, Dept. of the Interior (1995)
1995 Best Paper Award, Jour. Great Lakes Res.
1994 Elected Fellow, Geological Society of America
1993 Visiting Fellow, Institute for Rock Magnetism, Univ. Minnesota
1992 Best Paper Award, Geophysics
Science and Products
Physical and chemical data for dust deposited on Colorado Rocky Mountain snow cover during water year 2013 through water year 2016.
Atmospheric particulate matter deposited to snow cover diminishes snow-surface albedo and results in early onset and rapid snow melting, challenging management of downstream water resources. We present here physical and chemical data from snow samples from 14 sites during the melt seasons of water years 2013-16 across 60,000 km2 of the central Rocky Mountains within the Upper Colorado River basin.
Climate Impact Meteorological Stations (CLIM-MET) data from Canyonlands National Park, Utah
These CLIM-MET stations are meteorological/geological stations that is designed to function in remote areas for long periods of time without human intervention. These stations measure meteorological and wind-erosion parameters under varying climatic and land-use conditions to detect and describe ongoing landscape changes. These data represent multiple years of local detailed landscape and environm
Data for Dust deposited on snow cover in the San Juan Mountains, Colorado, 2011-2016: Compositional variability bearing on snow-melt effects
Light-absorbing particles in atmospheric dust deposited on snow cover (dust-on-snow, DOS) diminish albedo and accelerate the timing and rate of snow melt. Identification of these particles and their effects are relevant to snow-radiation modeling and water-resource management. Laboratory-measured reflectance of DOS samples from the San Juan Mountains (USA) were compared with DOS mass loading, part
Filter Total Items: 116
Dust in the Critical Zone: North American case studies
The dust cycle facilitates the exchange of particles among Earth's major systems, enabling dust to traverse ecosystems, cross geographic boundaries, and even move uphill against the natural flow of gravity. Dust in the atmosphere is composed of a complex and ever-changing mixture that reflects the evolving human footprint on the landscape. The emission, transport, and deposition of dust interacts
Authors
Janice Brahney, Ruth C. Heindel, Thomas E. Gill, Gregory Carling, Juan M Gonzalez-Olalla, Jenny L. Hand, Derek V. Mallia, Jeffrey S. Munroe, Kevin Perry, Annie L. Putman, S. McKenzie Skiles, Brad R. Adams, Zachary T. Aanderud, Sarah M. Aarons, Daniela Aguirre, Karin Ardon-Dryer, Molly Ann Blakowski, Jessie M. Creamean, Diego P. Fernandez, Hosein Foroutan, Cassandra J. Gaston, Maura Hahnenberger, Sebastian W. Hoch, Daniel Jones, Kerry E. Kelly, Otto I. Lang, Josh Lemonte, Richard L. Reynolds, Ramesh P. Singh, Mark Sweeney, Thorn K. Merrill
Microplastic and associated black particles from road-tire wear: Implications for radiative effects across the cryosphere and in the atmosphere
The environmental effects of airborne micro- and nano-size plastic particles are poorly understood. Microscopy and chemical analyses of atmospherically deposited particles on snow surfaces at high elevation (2,865–3,690 m) in the Upper Colorado River basin (UCRB; Colorado Rocky Mountains) revealed the presence of black substances intimately associated with microplastic fibers, particles interprete
Authors
Richard L. Reynolds, Heather A. Lowers, George N. Breit, Harland L. Goldstein, Elizabeth Kellisha Williams, Corey Lawrence, Raymond F. Kokaly, Jeff Derry
Microplastic particles in dust-on-snow, Upper Colorado River Basin, Colorado Rocky Mountains, 2013–16
Atmospheric dust deposited to snow cover (dust-on-snow) diminishes snow-surface albedo (SSA) to result in early onset and accelerated rate of melting, effects that challenge management of downstream water resources. During ongoing investigations to identify the light-energy absorbing dust particles most responsible for diminished SSA in the Upper Colorado River Basin of the Colorado Rocky Mountain
Authors
Richard L. Reynolds, Harland L. Goldstein, Raymond F. Kokaly, Jeff Derry
Atmospheric processing of iron-bearing mineral dust aerosol and its effect on growth of a marine diatom, Cyclotella meneghiniana
Iron (Fe) is a growth-limiting micronutrient for phytoplankton in major areas of oceans and deposited wind-blown desert dust is a primary Fe source to these regions. Simulated atmospheric processing of four mineral dust proxies and two natural dust samples followed by subsequent growth studies of the marine planktic diatom Cyclotella meneghiniana in artificial sea-water (ASW) demonstrated higher g
Authors
Eshani Hettiarachchi, Sergei Ivanov, Thomas L. Kieft, Harland L. Goldstein, Bruce M. Moskowitz, Richard L. Reynolds, Gayan Rubasinghege
Dust deposited on snow cover in the San Juan Mountains, Colorado, 2011-2016: Compositional variability bearing on snow-melt effects
Light-absorbing particles in atmospheric dust deposited on snow cover (dust-on-snow, DOS) diminish albedo and accelerate the timing and rate of snow melt. Identification of these particles and their effects are relevant to snow-radiation modeling and thus water-resource management. Laboratory-measured reflectance of DOS samples from the San Juan Mountains (USA) were compared with DOS mass loading,
Authors
Richard L. Reynolds, Harland L. Goldstein, Bruce M. Moskowitz, Raymond F. Kokaly, Seth M. Munson, Peat Solheid, George N. Breit, Corey R. Lawrence, Jeff Derry
Bioavailable iron production in airborne mineral dust: Controls by chemical composition and solar flux
A large part of oceanic biological production is limited by the scarcity of dissolved iron. Mineral dust aerosol, processed under acidic atmospheric conditions, is the primary natural source of bioavailable iron to oceanic life. However, synergistic and antagonistic effects of non-Fe-containing minerals on atmospheric processing of Fe-containing minerals and Fe solubilization are poorly understood
Authors
Eshani Hettiarachchi, Richard L. Reynolds, Harland L. Goldstein, Bruce M. Moskowitz, Gayan Rubasinghege
Iron dissolution and speciation in atmospheric mineral dust: Metal-metal synergistic and antagonistic effects
Under acidic atmospheric conditions, iron leached from atmospheric mineral dust may influence the distribution of bioavailable iron at a global scale. However, the effects of non-Fe-containing minerals on iron dissolution remain unknown. This work describes metal-metal synergistic and antagonistic effects on iron dissolution that go beyond aggregation and ionic strength effects in mineral dust mix
Authors
Eshani Hettiarachchi, Richard L. Reynolds, Harland L. Goldstein, Bruce M. Moskowitz, Gayan Rubasinghege
Phosphorus speciation and solubility in aeolian dust deposited in the interior American West
Aeolian dust is a significant source of phosphorus (P) to alpine oligotrophic lakes, but P speciation in dust and source sediments and its release kinetics to lake water remain unknown. Phosphorus K-edge XANES spectroscopy shows that calcium-bound P (Ca−P) is dominant in 10 of 12 dust samples (41−74%) deposited on snow in the central Rocky Mountains and all 42 source sediment samples (the fine fra
Authors
Zhuojun Zhang, Harland L. Goldstein, Richard L. Reynolds, Yongfeng Hu, Xiaoming Wang, Mengqiang Zhu
Late Quaternary loess and soils on uplands in the Canyonlands and Mesa Verde areas, Utah and Colorado
Thin loess deposits on the uplands of the southeastern Colorado Plateau have previously not been well studied. We sampled deposits and soils from trenches on Hatch Point (HP) mesa near Canyonlands National Park, Utah, and from two outcrops in Mesa Verde National Park, Colorado. At HP, the oldest buried unit yielded 2 optically stimulated luminescence (OSL) ages of 10,370 and 7555 yr; the middle un
Authors
Marith C. Reheis, Harland L. Goldstein, Richard L. Reynolds, Steven L. Forman, Shannon A. Mahan, Paul E. Carrara
Controls on the chemical composition of saline surface crusts and emitted dust from a wet playa in the Mojave Desert (USA)
Saline-surface crusts and their compositions at ephemeral, dry, and drying lakes are important products of arid-land processes. Detailed understanding is lacking, however, about interactions among locally variable hydrogeologic conditions, compositional control of groundwater on vadose zone and surface salts, and dust composition. Chemical and physical data from groundwater, sediments, and salts r
Authors
Harland L. Goldstein, George N. Breit, Richard L. Reynolds
Concentrations of mineral aerosol from desert to plains across the central Rocky Mountains, western United States
Mineral dusts can have profound effects on climate, clouds, ecosystem processes, and human health. Because regional dust emission and deposition in western North America are not well understood, measurements of total suspended particulate (TSP) from 2011 to 2013 were made along a 500-km transect of five remote sites in Utah and Colorado, USA. The TSP concentrations in μg m−3 adjusted to a 24-h per
Authors
Richard L. Reynolds, Seth M. Munson, Daniel Fernandez, Harland L. Goldstein, Jason C. Neff
Iron oxide minerals in dust-source sediments from the Bodélé Depression, Chad: Implications for radiative properties and Fe bioavailability of dust plumes from the Sahara
Atmospheric mineral dust can influence climate and biogeochemical cycles. An important component of mineral dust is ferric oxide minerals (hematite and goethite) which have been shown to influence strongly the optical properties of dust plumes and thus affect the radiative forcing of global dust. Here we report on the iron mineralogy of dust-source samples from the Bodélé Depression (Chad, north-c
Authors
Bruce M. Moskowitz, Richard L. Reynolds, Harland L. Goldstein, Thelma Beroquo, Raymond F. Kokaly, Charlie S Bristow
Non-USGS Publications**
Larson, E.E., Reynolds, R.L., and others, 1975, Major element petrochemistry of some extrusive rocks from the volcanically active Mariana Islands: Bulletin Volcanologique, v. 39, p. 361-377.
Larson, E.E., Reynolds, R.L., and others, 1975, Paleomagnetism of Miocene volcanics of Guam and the curvature of the southern Mariana Island Arc: Geological Society America Bulletin, v. 86, p. 346‑350.
Levi, S., Merrill, R.T., Larson, E.E., Reynolds, R.L., and others, 1975, Paleosecular variation of lavas from the Marianas in the Western Pacific Ocean: Journal Geomagnetism and Geoelectricity, v. 27, p. 57-66.
Rowley, P.D., Williams, P.L., Schmidt, D.L., Reynolds, R.L., and others, 1975, Copper mineralization along the Lassiter Coast of the Antarctic Peninsula: Economic Geology, v. 70, p. 982‑992.
**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
Physical and chemical data for dust deposited on Colorado Rocky Mountain snow cover during water year 2013 through water year 2016.
Atmospheric particulate matter deposited to snow cover diminishes snow-surface albedo and results in early onset and rapid snow melting, challenging management of downstream water resources. We present here physical and chemical data from snow samples from 14 sites during the melt seasons of water years 2013-16 across 60,000 km2 of the central Rocky Mountains within the Upper Colorado River basin.
Climate Impact Meteorological Stations (CLIM-MET) data from Canyonlands National Park, Utah
These CLIM-MET stations are meteorological/geological stations that is designed to function in remote areas for long periods of time without human intervention. These stations measure meteorological and wind-erosion parameters under varying climatic and land-use conditions to detect and describe ongoing landscape changes. These data represent multiple years of local detailed landscape and environm
Data for Dust deposited on snow cover in the San Juan Mountains, Colorado, 2011-2016: Compositional variability bearing on snow-melt effects
Light-absorbing particles in atmospheric dust deposited on snow cover (dust-on-snow, DOS) diminish albedo and accelerate the timing and rate of snow melt. Identification of these particles and their effects are relevant to snow-radiation modeling and water-resource management. Laboratory-measured reflectance of DOS samples from the San Juan Mountains (USA) were compared with DOS mass loading, part
Filter Total Items: 116
Dust in the Critical Zone: North American case studies
The dust cycle facilitates the exchange of particles among Earth's major systems, enabling dust to traverse ecosystems, cross geographic boundaries, and even move uphill against the natural flow of gravity. Dust in the atmosphere is composed of a complex and ever-changing mixture that reflects the evolving human footprint on the landscape. The emission, transport, and deposition of dust interacts
Authors
Janice Brahney, Ruth C. Heindel, Thomas E. Gill, Gregory Carling, Juan M Gonzalez-Olalla, Jenny L. Hand, Derek V. Mallia, Jeffrey S. Munroe, Kevin Perry, Annie L. Putman, S. McKenzie Skiles, Brad R. Adams, Zachary T. Aanderud, Sarah M. Aarons, Daniela Aguirre, Karin Ardon-Dryer, Molly Ann Blakowski, Jessie M. Creamean, Diego P. Fernandez, Hosein Foroutan, Cassandra J. Gaston, Maura Hahnenberger, Sebastian W. Hoch, Daniel Jones, Kerry E. Kelly, Otto I. Lang, Josh Lemonte, Richard L. Reynolds, Ramesh P. Singh, Mark Sweeney, Thorn K. Merrill
Microplastic and associated black particles from road-tire wear: Implications for radiative effects across the cryosphere and in the atmosphere
The environmental effects of airborne micro- and nano-size plastic particles are poorly understood. Microscopy and chemical analyses of atmospherically deposited particles on snow surfaces at high elevation (2,865–3,690 m) in the Upper Colorado River basin (UCRB; Colorado Rocky Mountains) revealed the presence of black substances intimately associated with microplastic fibers, particles interprete
Authors
Richard L. Reynolds, Heather A. Lowers, George N. Breit, Harland L. Goldstein, Elizabeth Kellisha Williams, Corey Lawrence, Raymond F. Kokaly, Jeff Derry
Microplastic particles in dust-on-snow, Upper Colorado River Basin, Colorado Rocky Mountains, 2013–16
Atmospheric dust deposited to snow cover (dust-on-snow) diminishes snow-surface albedo (SSA) to result in early onset and accelerated rate of melting, effects that challenge management of downstream water resources. During ongoing investigations to identify the light-energy absorbing dust particles most responsible for diminished SSA in the Upper Colorado River Basin of the Colorado Rocky Mountain
Authors
Richard L. Reynolds, Harland L. Goldstein, Raymond F. Kokaly, Jeff Derry
Atmospheric processing of iron-bearing mineral dust aerosol and its effect on growth of a marine diatom, Cyclotella meneghiniana
Iron (Fe) is a growth-limiting micronutrient for phytoplankton in major areas of oceans and deposited wind-blown desert dust is a primary Fe source to these regions. Simulated atmospheric processing of four mineral dust proxies and two natural dust samples followed by subsequent growth studies of the marine planktic diatom Cyclotella meneghiniana in artificial sea-water (ASW) demonstrated higher g
Authors
Eshani Hettiarachchi, Sergei Ivanov, Thomas L. Kieft, Harland L. Goldstein, Bruce M. Moskowitz, Richard L. Reynolds, Gayan Rubasinghege
Dust deposited on snow cover in the San Juan Mountains, Colorado, 2011-2016: Compositional variability bearing on snow-melt effects
Light-absorbing particles in atmospheric dust deposited on snow cover (dust-on-snow, DOS) diminish albedo and accelerate the timing and rate of snow melt. Identification of these particles and their effects are relevant to snow-radiation modeling and thus water-resource management. Laboratory-measured reflectance of DOS samples from the San Juan Mountains (USA) were compared with DOS mass loading,
Authors
Richard L. Reynolds, Harland L. Goldstein, Bruce M. Moskowitz, Raymond F. Kokaly, Seth M. Munson, Peat Solheid, George N. Breit, Corey R. Lawrence, Jeff Derry
Bioavailable iron production in airborne mineral dust: Controls by chemical composition and solar flux
A large part of oceanic biological production is limited by the scarcity of dissolved iron. Mineral dust aerosol, processed under acidic atmospheric conditions, is the primary natural source of bioavailable iron to oceanic life. However, synergistic and antagonistic effects of non-Fe-containing minerals on atmospheric processing of Fe-containing minerals and Fe solubilization are poorly understood
Authors
Eshani Hettiarachchi, Richard L. Reynolds, Harland L. Goldstein, Bruce M. Moskowitz, Gayan Rubasinghege
Iron dissolution and speciation in atmospheric mineral dust: Metal-metal synergistic and antagonistic effects
Under acidic atmospheric conditions, iron leached from atmospheric mineral dust may influence the distribution of bioavailable iron at a global scale. However, the effects of non-Fe-containing minerals on iron dissolution remain unknown. This work describes metal-metal synergistic and antagonistic effects on iron dissolution that go beyond aggregation and ionic strength effects in mineral dust mix
Authors
Eshani Hettiarachchi, Richard L. Reynolds, Harland L. Goldstein, Bruce M. Moskowitz, Gayan Rubasinghege
Phosphorus speciation and solubility in aeolian dust deposited in the interior American West
Aeolian dust is a significant source of phosphorus (P) to alpine oligotrophic lakes, but P speciation in dust and source sediments and its release kinetics to lake water remain unknown. Phosphorus K-edge XANES spectroscopy shows that calcium-bound P (Ca−P) is dominant in 10 of 12 dust samples (41−74%) deposited on snow in the central Rocky Mountains and all 42 source sediment samples (the fine fra
Authors
Zhuojun Zhang, Harland L. Goldstein, Richard L. Reynolds, Yongfeng Hu, Xiaoming Wang, Mengqiang Zhu
Late Quaternary loess and soils on uplands in the Canyonlands and Mesa Verde areas, Utah and Colorado
Thin loess deposits on the uplands of the southeastern Colorado Plateau have previously not been well studied. We sampled deposits and soils from trenches on Hatch Point (HP) mesa near Canyonlands National Park, Utah, and from two outcrops in Mesa Verde National Park, Colorado. At HP, the oldest buried unit yielded 2 optically stimulated luminescence (OSL) ages of 10,370 and 7555 yr; the middle un
Authors
Marith C. Reheis, Harland L. Goldstein, Richard L. Reynolds, Steven L. Forman, Shannon A. Mahan, Paul E. Carrara
Controls on the chemical composition of saline surface crusts and emitted dust from a wet playa in the Mojave Desert (USA)
Saline-surface crusts and their compositions at ephemeral, dry, and drying lakes are important products of arid-land processes. Detailed understanding is lacking, however, about interactions among locally variable hydrogeologic conditions, compositional control of groundwater on vadose zone and surface salts, and dust composition. Chemical and physical data from groundwater, sediments, and salts r
Authors
Harland L. Goldstein, George N. Breit, Richard L. Reynolds
Concentrations of mineral aerosol from desert to plains across the central Rocky Mountains, western United States
Mineral dusts can have profound effects on climate, clouds, ecosystem processes, and human health. Because regional dust emission and deposition in western North America are not well understood, measurements of total suspended particulate (TSP) from 2011 to 2013 were made along a 500-km transect of five remote sites in Utah and Colorado, USA. The TSP concentrations in μg m−3 adjusted to a 24-h per
Authors
Richard L. Reynolds, Seth M. Munson, Daniel Fernandez, Harland L. Goldstein, Jason C. Neff
Iron oxide minerals in dust-source sediments from the Bodélé Depression, Chad: Implications for radiative properties and Fe bioavailability of dust plumes from the Sahara
Atmospheric mineral dust can influence climate and biogeochemical cycles. An important component of mineral dust is ferric oxide minerals (hematite and goethite) which have been shown to influence strongly the optical properties of dust plumes and thus affect the radiative forcing of global dust. Here we report on the iron mineralogy of dust-source samples from the Bodélé Depression (Chad, north-c
Authors
Bruce M. Moskowitz, Richard L. Reynolds, Harland L. Goldstein, Thelma Beroquo, Raymond F. Kokaly, Charlie S Bristow
Non-USGS Publications**
Larson, E.E., Reynolds, R.L., and others, 1975, Major element petrochemistry of some extrusive rocks from the volcanically active Mariana Islands: Bulletin Volcanologique, v. 39, p. 361-377.
Larson, E.E., Reynolds, R.L., and others, 1975, Paleomagnetism of Miocene volcanics of Guam and the curvature of the southern Mariana Island Arc: Geological Society America Bulletin, v. 86, p. 346‑350.
Levi, S., Merrill, R.T., Larson, E.E., Reynolds, R.L., and others, 1975, Paleosecular variation of lavas from the Marianas in the Western Pacific Ocean: Journal Geomagnetism and Geoelectricity, v. 27, p. 57-66.
Rowley, P.D., Williams, P.L., Schmidt, D.L., Reynolds, R.L., and others, 1975, Copper mineralization along the Lassiter Coast of the Antarctic Peninsula: Economic Geology, v. 70, p. 982‑992.
**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.
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government