Sheila Murphy
Biography
Sheila Murphy focuses on the characterization of the hydrology and water chemistry of watersheds and how they are affected by both natural factors and disturbance. Her recent research has evaluated the effects of wildfire on stream water quantity and quality in the Colorado Front Range, and the hydrologic and geochemical responses to geology, land cover change, and hurricanes in a tropical forest in Puerto Rico.
Publications:
Wetherbee, G.A., Benedict, K.B., Murphy, S.F., and Elliot, E., 2019, Inorganic nitrogen wet deposition gradients in the Denver-Boulder metropolitan area and Colorado Front Range – Preliminary implications for Rocky Mountain National Park and interpolated deposition maps: Science of the Total Environment, 691, p. 1027-1042, https://doi.org/10.1016/j.scitotenv.2019.06.528.
Murphy, S.F., McCleskey, R.B., Martin, D.A., Writer, J.H., and Ebel, B.A., 2018, Fire, flood, and drought—Extreme climate events alter flow paths and stream chemistry: Journal of Geophysical Research: Biogeosciences, 123, p. 2513-2526, https://doi.org/10.1029/2017JG004349.
Murphy, S. F., McCleskey, R. B., & Writer, J. H., 2018. Water chemistry data for Fourmile Creek Watershed, 2010-2015. U.S. Geological Survey database, https://doi.org/10.5066/F7Z60N8T.
Dethier, D.P., Ouimet, W.B., Murphy, S.F., Kotikian, M., Wicherski, W., and Samuel, R.M., 2018, Anthropocene landscape change and the legacy of 19th- and 20th-century mining in the Fourmile catchment, Colorado Front Range: Annals of American Geographers, 108(4)), pp. 917-937, https://doi.org/10.1080/24694452.2017.1406329.
McMillan, S.K., Wilson, H.F., Tague, C.L., Hanes, D.M., Inamdar, S., Karway, D.L., Loecke, T., Morrison, J., Murphy, S.F., and Vidon, P., 2018, Before the storm- Antecdent conditions as regulators of hydrologic and biogeochemical response to extreme climate events: Biogeochemistry, https://doi.org/10.1007/s10533-018-0482-6.
Murphy, S.F., Stallard, R.F., Scholl, M.A., González, G., Torres-Sánchez, A.J., 2017, Reassessing rainfall in the Luquillo Mountains, Puerto Rico: Local and global ecohydrological implications: PLOS ONE 12(7): e0180987. https://doi.org/10.1371/journal.pone.0180987.
Murphy, S.F., Stallard, R.F., Scholl, M.A., González, G., and Torres-Sánchez, A.J, 2017, Geospatial data for Luquillo Mountains, Puerto Rico: Mean annual precipitation, elevation, watershed outlines, and rain gage locations: U.S. Geological Survey data release, https://doi.org/10.5066/F74F1PM2.
Bassiouni, M., Scholl, M.A., Torres-Sanchez, A.J., Murphy, S.F., 2017, A method for quantifying cloud immersion in a tropical mountain forest using time-lapse photography: Agricultural and Forest Meteorology, 243, 100-112, http://dx.doi.org/10.1016/j.agrformet.2017.04.010.
Bassiouni, M., Scholl, M.A., Torres-Sanchez, A.J., and Murphy, S.F., 2017, Supplementary data for method for quantifying cloud immersion in a tropical mountain forest using time-lapse photography: U.S. Geological Survey Data Release, http://dx.doi.org/10.5066/F7HQ3X52.
Hinckley, E.-L.S., Ebel, B.A., Barnes, R.T., Murphy, S.F., and Anderson, S.P., 2017, Critical zone properties control the fate of Nitrogen during experimental rainfall in montane forests of the Colorado Front Range: Biogeochemistry, v. 132, pp 213–231, https://link.springer.com/article/10.1007/s10533-017-0299-8.
Mast, M.A., Murphy, S.F., Clow, D.W., Penn, C., and Sexstone, G., 2016, Water-quality response to a high-elevation wildfire in the Colorado Front Range: Hydrological Processes, DOI: 10.1002/hyp.10755 [Link]
Murphy, S.F.; Writer, J.H.; McCleskey, R.B.; Martin, D.A., 2015. The role of precipitation type, intensity, and spatial distribution in source water quality after wildfire: Environmental Research Letters, v. 10, no. 8, 084007: 1-13. doi:10.1088/1748-9326/10/8/08400713 [Link]
Scholl, M.A., Shanley, J.B., Murphy, S.F., Willenbring, J.K., Occhi, M., and Gonzalez, G., 2015, Stable-isotope and solute-chemistry approaches to flow characterization in a forested tropical watershed, Luquillo Mountains, Puerto Rico, Applied Geochemistry, doi:10.1016/j.apgeochem.2015.03.008 [Link]
Antweiler, R.C., Writer, J.H., and Murphy, S.F., 2014, Evaluation of wastewater contaminant transport in surface waters using verified Lagrangian sampling: Science of the Total Environment: v. 470–471, p. 551-558. [Link]
Stallard, R.F., and Murphy, S.F., 2014, A unified assessment of hydrological and biogeochemical responses in research watersheds in Eastern Puerto Rico using runoff-concentration relations: Aquatic Geochemistry, v. 20, pp 115-139: DOI 10.1007/s10498-013-9216-5. [Link]
Scholl, M.A. and Murphy, S.F., 2014, Precipitation isotopes link regional climate patterns to water supply in a tropical mountain forest, eastern Puerto Rico, Water Resources Research 50, doi: 10.1002/2013WR014413. [Link]
Murphy, S.F., McCleskey, R.B. & Writer J.W., 2012. Effects of flow regimes on stream turbidity and suspended solids after wildfire, Colorado Front Range, USA. IAHS Publ. 354. IAHS Press. Wallingford, UK.
Writer, J.H.; McClelskey, R. B.; Murphy, S.F., 2012. Effects of wildfire on source-water quality and aquatic ecosystems, Colorado Front Range. IAHS Publications , 6 p.
Murphy, S.F., and Stallard, R.F., eds., 2012, Water quality and landscape processes of four watersheds in eastern Puerto Rico: U.S. Geological Survey Professional Paper 1789. [Link]
Murphy, S.F., and Stallard, R.F., 2012, Hydrology and climate of four watersheds in eastern Puerto Rico, ch. C in Murphy, S.F., and Stallard, R.F., eds., Water quality and landscape processes of four watersheds in eastern Puerto Rico: U.S. Geological Survey Professional Paper 1789–C. [Link]
Murphy, S.F., Stallard, R.F., Larsen, M.C., and Gould, W.A., 2012, Physiography, geology, and land cover of four watersheds in eastern Puerto Rico—ch. A, in Murphy, S.F. and Stallard, R.F., eds., Water quality and landscape processes of four watersheds in eastern Puerto Rico: U.S. Geological Survey Professional Paper 1789–A. [Link]
Stallard, R.F., and Murphy, S.F., 2012, Water quality and mass transport in four watersheds in eastern Puerto Rico—ch. E, in Murphy, S.F., and Stallard, R.F., eds., Water quality and landscape processes of four watersheds in eastern Puerto Rico: U.S. Geological Survey Professional Paper 1789–E. [Link]
Writer, J.H. and Murphy, S.F., 2012, Wildfire Effects on Source-Water Quality—Lessons from Fourmile Canyon Fire, Colorado, and Implications for Drinking-Water Treatment: U.S. Geological Survey Fact Sheet 2012–3095, 4 p. [Link]
McCleskey, R.B., Writer, J.H., and Murphy, S.F., 2012, Water chemistry of surface waters affected by the Fourmile Canyon wildfire, Colorado, 2010–2011: U.S. Geological Survey Open-File Report 2012–1104, 11 p. [Link]
Murphy, S.F., and Writer, J.H., 2011, Evaluating the effects of wildfire on stream processes in a Colorado front range watershed, USA: Applied Geochemistry, v. 26, supplement 1, p. s.S363-S364. [Link]
Murphy, S.F. and Stallard, R.F., 2009. Primary factors affecting water quality and quantity in four watersheds in Eastern Puerto Rico, in Webb, R.M.T., and Semmens, D.J., eds, Proceedings of the Third Interagency Conference on Research in the Watersheds: Planning for an Uncertain Future: Monitoring, Integration, and Adaptation: U.S. Geological Survey Scientific Investigations Report 2009-5049. Estes Park, Colorado, September 9-11, 2008, p. 251-256. [Link]
Glynn, P.A., Larsen, M.C., Greene, E.A., Buss, H.L., Clow, D.W., Hunt, R.J., Mast, M.A., Murphy, S.F., Peters, N.E., Sebestyen, S.D., Shanley, J.B., and Walker, J.F., 2009, Selected Achievements, Science Directions, and New Opportunities for the WEBB Small Watershed Research Program, in Webb, R.M.T., and Semmens, D.J., eds, Proceedings of the Third Interagency Conference on Research in the Watersheds: Planning for an Uncertain Future: Monitoring, Integration, and Adaptation: U.S. Geological Survey Scientific Investigations Report 2009-5049, p. 39-52.[Link]
Verplanck P.L., Murphy S.F., Birkeland P.W., Pitlick J., Barber L.B., and Schmidt, T.S., 2008, Boulder Creek—A stream ecosystem in an urban landscape, in R.G. Raynolds, ed., Roaming the Rocky Mountains and Environs—Geological Field Trips: GSA Field Guide Vol. 10, No. 0 pp. 217–233. [Link]
Murphy, S.F., 2006. State of the watershed: water quality of Boulder Creek, Colorado. Circular 1284, 34 p. [Link]
Barber, L.B., Murphy, S.F., Verplanck, P.L., Sandstrom, M.W., Taylor, H.E., and Furlong, E.T., 2006, Chemical loading into surface water along a hydrological, biogeochemical, and land use gradient—A holistic watershed approach: Environmental Science and Technology, v. 40, p. 475–486. [Link]
Murphy, S.F.; Verplanck, P.L.; Barber, L.B., editors, 2003. Comprehensive water quality of the Boulder Creek Watershed, Colorado, during high-flow and low-flow conditions, 2000. Water-Resources Investigations Report 2003-4045, xiii, 198 p. : ill., maps (some col.) ; 28 cm. [Link]
Verplanck, P.L.; Murphy, S.F.; Barber, L.B., 2003. Water quality of the Boulder Creek Watershed, Colorado. Fact Sheet 043-03, 1 folded sheet ([4] p.) : col. ill., col. map ; 28 cm. [Link]
Murphy, S.F., Barber, L.B., Verplanck, P.L., and Kinner, D.A., 2003, Environmental setting and hydrology of the Boulder Creek Watershed– Chapter 1 in Murphy, S.F., Verplanck, P.L., and Barber, L.B., eds., Comprehensive water quality of the Boulder Creek Watershed, Colorado, during high-flow and low-flow conditions, 2000: U.S. Geological Survey Water-Resources Investigations Report 03-4045, p. 5-26. [Link]
Murphy, S.F., Shelley, J.J., Stout, J.A., and Mead, E.P., 2003, Basic water quality in the Boulder Creek Watershed, Colorado, during high-flow and low-flow conditions, 2000– Chapter 3 in Murphy, S.F., Verplanck, P.L., and Barber, L.B., eds., Comprehensive water quality of the Boulder Creek Watershed, Colorado, during high-flow and low-flow conditions, 2000: U.S. Geological Survey Water-Resources Investigations Report 03-4045, p. 41-70. [Link]
Schramke, J.A., Murphy, S.F., Doucette, W.J., and Hintze, W.D., 1999, Prediction of aqueous diffusion coefficients for organic compounds at 25°C: Chemosphere, vol. 38, issue 10, pp. 2381-2406. [Link]
Murphy, S.F., Brantley, S.L., Blum, A.E., White, A.F., and Dong, H., 1998, Chemical weathering in a tropical mountain watershed, Luquillo Mountains, Puerto Rico II– The rate and mechanism of biotite weathering: Geochimica et Cosmochimica Acta, vol. 62, no. 2, pp. 227-243.[Link]
White, A.F., Blum, A.E., Schulz, M.S., Vivit, D., Stonestrom, D.A., Larsen, M.C., Murphy, S.F., and Eberl, D.D., 1998, Chemical weathering in a tropical mountain watershed, Luquillo Mountains, Puerto Rico I– Weathering rates based on mineral and solute mass balances: Geochimica et Cosmochimica Acta, vol. 62, no. 2, pp. 209-226. [Link]
Dong, H., Peacor, D.R., and Murphy, S.F., 1998, TEM study of progressive weathering of igneous biotite to kaolinite throughout a weathered soil profile: Geochimica et Cosmochimica Acta, vol. 62, no. 11, pp. 1881-1887. [Link]
Science and Products
Connections between Forested and Urban Landscapes and Implications for Water Supply
Interactions between forested and urban landscapes can lead to reciprocal effects that have substantial impacts on water supply and ecology. Air pollution from urban and forested landscapes can be deposited on adjacent forests, while forest disturbance, such as wildfires and floods, can remobilize those contaminants. Additionally, pollutants from legacy land use (e.g., mining) can also be...
Fire, flood, and drought: Extreme climate events alter flow paths and stream chemistry
Extreme climate events—such as hurricanes, droughts, extreme precipitation, and wildfires—have the potential to alter watershed processes and stream response. Yet due to the destructive and hazardous nature and unpredictability of such events, capturing their hydrochemical signal is challenging. A 5‐year postwildfire study of stream chemistry in...
Murphy, Sheila F.; McCleskey, R. Blaine; Martin, Deborah A.; Writer, Jeffrey H.; Ebel, Brian A. Before the storm: Antecedent conditions as regulators of hydrologic and biogeochemical response to extreme climate events
While the influence of antecedent conditions on watershed function is widely recognized under typical hydrologic regimes, gaps remain in the context of extreme climate events (ECEs). ECEs are those events that far exceed seasonal norms of intensity, duration, or impact upon the physical environment or ecosystem. In this synthesis, we discuss the...
McMillan, Sara K.; Wilson, Henry F.; Tague, Christina L.; Hanes, Daniel M.; Inamdar, Shreeram; Karwan, Diana L.; Loecke, Terry; Morrison, Jonathan; Murphy, Sheila F.; Vidon, Philippe Anthropocene landscape change and the legacy of nineteenth- and twentieth-century mining in the Fourmile Catchment, Colorado Front Range
Human impacts on earth surface processes and materials are fundamental to understanding the proposed Anthropocene epoch. This study examines the magnitude, distribution, and long-term context of nineteenth- and twentieth-century mining in the Fourmile Creek catchment, Colorado, coupling airborne LiDAR topographic analysis with historical documents...
Dethier, David P.; Ouimet, William B.; Murphy, Sheila F.; Kotikian, Maneh; Wicherski, Will; Samuels, Rachel M. A method for quantifying cloud immersion in a tropical mountain forest using time-lapse photography
Quantifying the frequency, duration, and elevation range of fog or cloud immersion is essential to estimate cloud water deposition in water budgets and to understand the ecohydrology of cloud forests. The goal of this study was to develop a low-cost and high spatial-coverage method to detect occurrence of cloud immersion within a mountain cloud...
Bassiouni, Maoya; Scholl, Martha A.; Torres-Sanchez, Angel J.; Murphy, Sheila F. Reassessing rainfall in the Luquillo Mountains, Puerto Rico: Local and global ecohydrological implications
Mountains receive a greater proportion of precipitation than other environments, and thus make a disproportionate contribution to the world’s water supply. The Luquillo Mountains receive the highest rainfall on the island of Puerto Rico and serve as a critical source of water to surrounding communities. The area’s role as a long-term research site...
Murphy, Sheila F.; Stallard, Robert F.; Scholl, Martha A.; Gonzalez, Grizelle; Torres-Sanchez, Angel J. Critical zone properties control the fate of nitrogen during experimental rainfall in montane forests of the Colorado Front Range
Several decades of research in alpine ecosystems have demonstrated links among the critical zone, hydrologic response, and the fate of elevated atmospheric nitrogen (N) deposition. Less research has occurred in mid-elevation forests, which may be important for retaining atmospheric N deposition. To explore the fate of N in the montane zone, we...
Hinckley, Eve-Lyn S.; Ebel, Brian A.; Barnes, Rebecca T.; Murphy, Sheila F.; Anderson, Suzanne P. Water-quality response to a high-elevation wildfire in the Colorado Front Range
Water quality of the Big Thompson River in the Front Range of Colorado was studied for 2 years following a high-elevation wildfire that started in October 2012 and burned 15% of the watershed. A combination of fixed-interval sampling and continuous water-quality monitors was used to examine the timing and magnitude of water-quality changes...
Mast, M. Alisa; Murphy, Sheila F.; Clow, David W.; Penn, Colin A.; Sexstone, Graham A. The role of precipitation type, intensity, and spatial distribution in source water quality after wildfire
Storms following wildfires are known to impair drinking water supplies in the southwestern United States, yet our understanding of the role of precipitation in post-wildfire water quality is far from complete. We quantitatively assessed water-quality impacts of different hydrologic events in the Colorado Front Range and found that for a three-year...
Murphy, Sheila F.; Writer, Jeffrey H.; McCleskey, R. Blaine; Martin, Deborah A. Stable-isotope and solute-chemistry approaches to flow characterization in a forested tropical watershed, Luquillo Mountains, Puerto Rico
The prospect of changing climate has led to uncertainty about the resilience of forested mountain watersheds in the tropics. In watersheds where frequent, high rainfall provides ample runoff, we often lack understanding of how the system will respond under conditions of decreased rainfall or drought. Factors that govern water supply, such as...
Scholl, Martha A.; Shanley, James B.; Murphy, Sheila F.; Willenbring, Jane K; Occhi, Marcie; González, Grizelle Precipitation isotopes link regional climate patterns to water supply in a tropical mountain forest, eastern Puerto Rico
Like many mountainous areas in the tropics, watersheds in the Luquillo Mountains of eastern Puerto Rico have abundant rainfall and stream discharge and provide much of the water supply for the densely populated metropolitan areas nearby. Projected changes in regional temperature and atmospheric dynamics as a result of global warming suggest that...
Scholl, Martha A.; Murphy, Sheila F. A unified assessment of hydrological and biogeochemical responses in research watersheds in Eastern Puerto Rico using runoff-concentration relations
An examination of the relation between runoff rate, R, and concentration, C, of twelve major constituents in four small watersheds in eastern Puerto Rico demonstrates a consistent pattern of responses. For solutes that are not substantially bioactive (alkalinity, silica, calcium, magnesium, sodium, and chloride), the log(R)–log(C)...
Stallard, Robert F.; Murphy, Sheila F. Evaluation of wastewater contaminant transport in surface waters using verified Lagrangian sampling
Contaminants released from wastewater treatment plants can persist in surface waters for substantial distances. Much research has gone into evaluating the fate and transport of these contaminants, but this work has often assumed constant flow from wastewater treatment plants. However, effluent discharge commonly varies widely over a 24-hour period...
Antweiler, Ronald C.; Writer, Jeffrey H.; Murphy, Sheila F.