Nan Walker headshotNan D. Walker

Position: Professor and James P. Morgan Distinguished Professor of Coastal Studies, Department of Oceanography & Coastal Sciences; Director, Earth Scan Laboratory

Phone: 225-578-2395

Fax: 225-578-2520


Bachelor's Degree(s): B.S. Duke University, 1976

Master's Degrees(s): M.S. Louisiana State University, 1982

Ph.D.(s): Ph.D. University of Cape Town, 1989

Research Interests

Physical oceanography, Satellite oceanography, Estuarine-shelf exchange processes, Air-sea interactions and tropical cyclone intensity, Gulf of Mexico Loop Current and eddy circulations, Physical-biological interactions, Physical processes affecting coral reef health

Classes Taught

OCS 1005. Introduction to Oceanography
OCS 2007. Physical and Geological Oceanography
OCS 7170. Satellite Oceanography
OCS 8900. Advanced Reading and Literature Research

Recent Publications

Google Scholar Profile

Chapman, P., DiMarco, S. F., Knap, A. H., Quigg, A., and Walker, N. D.: The effects of Hurricane Harvey on Texas coastal-zone chemistry, Ocean Sci., 19, 209–227,, 2023.

*Payandeh, Ali Reza, Dubravko Justic, Giulio Mariotti, Haosheng Huang, Kendall Valentine, Nan D. Walker, Suspended sediment dynamics in a deltaic estuary controlled by subtidal motion and offshore river plumes, Estuarine, Coastal and Shelf Science, 250 (2021) 107137, 13pp, 2021.

*Iles, Robert L., Nan D. Walker, John R. White and Robert V. Rohli, Impacts of a major Mississippi River freshwater diversion on suspended sediment plume kinematics in Lake Pontchartrain, a semi-enclosed Gulf of Mexico Estuary, Estuaries and Coasts, DOI 10.1007/s12237-020-00789-y, 2020.

*Ford, Victoria L., Nan D. Walker, a central and eastern North Pacific Ocean during the 2014 hurricane season and relationships to three major hurricanes, Journal of Marine Science and Engineering, 8, 288; doi:10.3390/jmse8040288, 2020.

*Abolfazli, Ehsan, Jun-Hong Liang, Yalin Fan, Qin Jim Chen, Nan D. Walker, Jinliang Liu, Surface gravity waves and their role in ocean-atmospheric coupling in the Gulf of Mexico, Journal of Geophysical Research: Oceans, 125, e2018JC014820., 2020. 

Smith, T., J.K. Jolliff, N.D. Walker, S. Anderson, Biophysical submesoscale processes in the wake of Hurricane Ivan: simulations and satellite observations, Journal of Marine Science and Engineering, 7, 378; doi:10.3390/jmse7110378, 2019.

*Z. Zang, Z.G. Xue, S. Bao, Q. Chen, N. Walker, A. Haag, Q. Ge, Z. Yao, A numerical study of sediment dynamics during hurricane Gustav, Ocean Modeling, 126, 29-42, 2018.

*Stevens, C., L.J. Thibodeaux, E.B. Overton, K.T. Valsaraj, N. and N. D. Walker,  Dissolution and heavy residue sinking of subsurface oil droplets: Binary component mixture dissolution theory and model-oil experiments, J. Environ. Engineering, 143(10): 04017067, DO: 10.1061/(ASCE)EE.1943-7870.0001242, 2017.

*Stevens, C., L.J. Thibodeaux, E.B. Overton, K.T. Valsaraj, N., K. Nandakumar, A. Rao and N. D. Walker, Sea surface oil slick light component vaporization and heavy residue sinking: binary mixture theory and experimental proof-of-concept, Environmental Engineering Science, DOI: 10.1089/ees.2015.0022, 2015.

*Zaihong, Z., Z. Deng, K.A. Rusch, and N.D. Walker, Modeling system for predicting Enterococci levels at Holly Beach, Marine Environmental Research, 109 (140-147),, 2015.

Walker, N.D, R.R. Leben, C.T. Pilley, M. Shannon, D.C. Herndon, I.F. Pun, I.-I. Lin,  C.L. Gentemann, Slow translation speed causes rapid collapse of East Pacific Hurricane Kenneth over a cold core eddy, Geophysical Research Letters, 41, doi:10.1002/2014GL061584, 2014.

Kolker, A.S., C. Li, N.D. Walker, C. Pilley, A. Ameen, G. Boxer, C. Ramatchandirane, M. Ullah, and K. Williams, The impacts of the Great Mississippi/Atchafalaya River flood on the oceanography of the inner Continental Shelf, Continental Shelf Research,, 2014.

Muller-Karger, F., M. Roffer, N. Walker, M. Oliver, O. Schofield, M. Abbott, H. Graber, R. Leben, G. Goni, Satellite remote sensing in support of an integrated ocean observing system, IEEE Geoscience and Remote Sensing Magazine, 8-18, 2013.

Huang, H., N.D. Walker, Y. Hsueh, Y. Chao, and R. Leben, An Analysis of Loop Current frontal eddies in a 1/6° Atlantic Ocean model simulation, Journal of Physical Oceanography, 43, DOI: 10.1175/JPO-D-12-0227.1, 1924-1939, 2013.

*C., Nazanin, E. D’Sa, D. S. Ko, N. D. Walker, C. L. Osburn, R. F. Chen, Colored dissolved organic matter dynamics in the northern Gulf of Mexico from ocean color and numerical model results, Journal of Coastal Research, DOI: 10.2112/JCOASTRES-D-13-00036, 2013.

Bianchi, T., S., F. Garcia-Tigreros, S. A. Yvon-Lewis, M. Shields, H. J. Mills, D. Butman, C. Osburn, P. Raymond, G. C. Shank, S. F. DiMarco, N. Walker, B. K. Reese, R. Mullins-Perry, A. Quigg, G. R. Aiden and E. L. Grossman, Enhanced transfer of terrestrially derived carbon to the atmosphere in a flooding event, Geophysical Research Letters, 40, 1-7, doi:10.1029/2012GL054145, 2013.

*Dash, P., N. Walker, D. Mishra, E. D’Sa, S. Ladner, Atmospheric correction and vicarious calibration of Oceansat-1 Ocean Color Monitor (OCM) data in coastal case 2 waters, Remote Sensing, 4, 1716-1740, doi:10.3390/rs4061716, 2012.

Weeks, E., C. Li, H. Roberts, R. Shaw, N. Walker, A comparison of an unmanned survey vessel to manned vessels for nearshore tidal current and transport measurements, Marine Technology Society Journal, 45: 71-77, 2012.

Walker, N. D., C. T. Pilley, V. V. Raghunathan, E. J. D'Sa, R. R. Leben,  N. G. Hoffmann, P. J. Brickley, P. D. Coholan, N. Sharma, H. C. Graber, R. E. Turner, 2011, Impacts of a Loop Current frontal eddy cyclone and wind forcing on the 2010 Gulf of Mexico oil spill, AGU Monograph Series 195, Monitoring and Modeling the Deepwater Horizon Oil Spill: a Record-Breaking Enterprise, Editors Y. Liu, A. MacFadyen, Z. Ji and R. Weisberg, 10.1029/2011GM001120, 103-116, 2011.

Whitehead, B. Dubansky, C. Bodinier, T. I. Garcia, S. Miles, C. Pilley, V. Raghunathan, J. L. Roach, N. Walker, R. B. Walter, C. D. Rice, and F. Galvez, 2011, Genomic and physiological footprint of the Deepwater Horizon oil spill on resident marsh fishes, Proceedings of the National Academy of Sciences, 1109545108v1-201109545, 2011.

*R. V. Schiller, V. H. Kourafalou, P. Hogan, N. D. Walker, The dynamics of the Mississippi River Plume: impact of topography, wind and offshore forcing on the fate of plume waters, Journal of Geophysical Research 116, C06029, doi.1029/2010JC006883, 2011.

*Dash, P., N. D. Walker, D. R. Mishra, C. Hu, J. L. Pinckney, E.J. D’Sa, Quantification of cyanobacterial pigments using Oceansat-1 OCM satellite data, Remote Sensing of Environment, doi:10.10.1016/j.rse.2011.08.004, 2011

*Zhao, H., Q. Chen, N. D. Walker, Q. Zheng, H. L. MacIntyre, A study of sediment transport in a shallow estuary using MODIS imagery and particle tracking simulation, International Journal of Remote Sensing: 32, 6653-6671, 2011.

Zheng, Q., Z. Qing, N. D. Walker, C. Li, Oil spill in the Gulf of Mexico and spiral vortex, Acta Oceanologica Sinica, Vol 29, 1-2, 2010.

*Garcia, A. C., S. Bargu, P. Dash, N. Rabalais, M. Sutor, W. Morrison, and N. Walker, Evaluating the potential risk of microcystins to blue crab (Callinectes sapidus) fisheries and human health in a eutrophic estuary, Harmful Algae, Vol. 9, 134-143, 2010.

DiMarco, S.F., P. Chapman, N.D. Walker, and R.D. Hetland, Does local topography control hypoxia on the eastern Texas-Louisiana shelf, Journal of Marine Systems, doi:10.1016/j.jmarsys.2009.08.005, 2009.

White, J.R., R.W. Fulweiler, C.Y. Li, S. Bargu, N. Walker, R.R. Twilley and S.E. Green, The Mississippi River Flood of 2008: observations of a large freshwater diversion on physical, chemical and biological characteristics of a shallow estuarine lake, Environmental Science and Technology, Vol. 43, no. 15, 5599-5604, doi: 10.1021/es900318t, 2009.

Pinckney, J.L., J.L. Wee, A. Hou, and N.D. Walker, Phytoplankton community structure responses to urban effluent inputs following Hurricanes Katrina and Rita, Marine Ecology Progress Series, doi:10.3354/meps08091, 2009.

*Kiage, L. M., N. D. Walker, Monitoring the summer maxima of duckweed blooms in Lake Maracaibo, Venezuela using MODIS data: 2003-2006, Water Resources Management, 23: 1125-1135, DOI 10.1007/s11269-008-9318-9, 2009. 

Li, C., N. Walker, A. Hou, I. Georgiou, H.H. Roberts, E. Laws, J.A. McCorquodale, E. Weeks, X. Li, J. Crochet, Circular plumes in Lake Pontchartrain under wind straining, Estuarine, Coastal and Shelf Science 80, 161-172, 2008.

Cobb, M., T. Keen and N. Walker, Modeling the circulation of the Atchafalaya Bay system: 1. Model description and validation, Journal of Coastal Research, 24 (4), 1036-1047, 2008.

Cobb, M., T. Keen and N. Walker, Modeling the circulation of the Atchafalaya Bay system: 2. River plume dynamics during cold fronts, Journal of Coastal Research, 24 (4), 1048-1062, 2008.

*Kiage, L., K. Liu, N. Lam, N. Walker, O. Huh, Recent land-cover/use change associated with land degradation in the Lake Baringo catchment, Kenya, East Africa: evidence from Landsat TM ad ETM+, International Journal of Remote Sensing, 28 (19), 1-25, 2007.

Walker, N.D. and N. N. Rabalais, Relationships among satellite chlorophyll a, river inputs and hypoxia on the Louisiana continental shelf, Gulf of Mexico, Estuaries and Coasts, 9 (6b), 1-13, 2006. 

Green, R.E., T.S. Bianchi, M.J. Dagg, N.D. Walker, Application of a physical-biological model for the Mississippi River plume to the determination of an organic carbon budget, air-sea CO2 fluxes, and contributions to bottom-water hypoxia, Estuaries and Coasts, 29 (4), 579-597, 2006.

Walker, N.D., A. Haag, S. Balasubramanian, R. Leben, I. van Heerden, P. Kemp, H. Mashriqui, Hurricane prediction: a century of advances, Oceanography, vol. 19, no. 2, June 2006

Walker, N., Wind- and eddy-related shelf/slope circulation processes and coastal upwelling in the northwestern Gulf of Mexico, in AGU Monograph Series, New Developments in the Circulation of the Gulf of Mexico, W. Sturges III and A. Lugo-Fernandez, Eds., 295-314, 2005. 

*Kiage, L., N.D. Walker, S. Balasubramanian, J. Barras, Applications of Radarsat-1 synthetic aperture radar imagery to assess hurricane related flooding of coastal Louisiana, International Journal of Remote Sensing, 26, 5359-5380, 2005. 

Walker, N.D., R.R. Leben, S. Balasubramanian, Hurricane-forced upwelling and chlorophyll a enhancement within cold-core cyclones in the Gulf of Mexico, Geophysical Research Letters, 32, L18610, doi:10.1029/2005GL023716, 2005. 

Stone, G., N. Walker, S.A. Hsu, A. Babin, B. Liu, B. Keim, W. Teague, D. Mitchell, R. Leben, What have we learned about Hurricane Ivan and its impacts along the northern Gulf of Mexico, EOS Transactions, American Geophysical Union, 86, 497-508, 2005.

Walker, N. D., W. J. Wiseman, L. J. Rouse, Jr., and A. Babin, Effects of river discharge, wind stress, and slope eddies on circulation and the satellite observed structure of the Mississippi River plume, Journal of Coastal Research, 21(6), 2005. 

Walker, N., S. Myint, A. Babin and A. Haag, Advances in satellite radiometry for the surveillance of surface temperatures, ocean eddies and upwelling processes in the Gulf of Mexico using GOES-8 measurements during summer, Geophysical Research Letters, Vol. 30, no. 16, 1854, doi:10.1029/2003GL-17555, 2003.

*Myint, S. and N. Walker, Quantification of surface suspended sediments along a river dominated coast with NOAA AVHRR and SeaWiFS measurements: Louisiana, USA, International Journal of Remote Sensing, Vol. 23, no. 16, 3229-3249, 2002.

Walker, N.D., Tropical and extra-tropical storm impacts on circulation, sediment and salt flux: Atchafalaya-Vermilion Bay region, Louisiana coast, Estuaries, 24, 498-508, 2001.

Huh, O.K., N.D. Walker and C. Moeller, Sedimentation along the Eastern Chenier Plain Coast: Down drift impact of a delta complex shift, Journal of Coastal Research, vol. 17, 72-81, 2001. 

Walker, N.D. and A.B. Hammack, Impacts of winter storms on circulation and sediment transport: Atchafalaya-Vermilion Bay region, Louisiana, Journal of Coastal Research, vol. 16, 4, 996-1010, 2000.

Hitchcock, G.L., W.J. Wiseman, W.C. Boicourt, A.J. Mariano, N. Walker, T.A. Nelsen, E. Ryan, Property fields in an effluent plume of the Mississippi River, Journal of Marine Systems, 12, 109-126, 1997.

Adams, C.E., Jr., L. Xu, N.D. Walker and S.P. Murray, Flow and sediment transport in a shallow bar-built estuary, northern Gulf of Mexico, Journal of Coastal Research, 13, 164-180, 1997.

Walker, N.D., Satellite assessment of Mississippi River plume variability: causes and predictability, Remote Sensing of Environment, Vol. 58, no. 1, 21-35, 1996. 

Walker, N.D., O.K. Huh, L.J. Rouse, and S.P. Murray, Evolution and structure of a coastal squirt off the Mississippi River delta: northern Gulf of Mexico, Journal of Geophysical Research, Vol. 101, no. C9, 20,643-20,655, 1996.

Schumann, S., G.A. Johnson, J. Moser, N.D. Walker, and S.A. Hsu, An overview of a strong winter low in the Gulf of Mexico, March 12-13, 1993, National Weather Digest, Vol. 20, no. 1, 11-25, 1995.

Walker, N.D., G. Fargion, L.J. Rouse, D. Biggs, The great flood of summer 1993: Mississippi River discharge studied, Earth in Space, American Geophysical Union, Nov. 1994 Issue, 11-14, 1994. 

Walker, N.D., G. Fargion, L.J. Rouse, D. Biggs, The great flood of summer 1993: Mississippi River discharge studied, EOS Transactions, American Geophysical Union, Vol. 75, No. 36, 409-415, 1994. 

Walker, N.D., O.K. Huh and L.J. Rouse, Jr., Warm-core eddy discovered in the Gulf of Mexico, EOS Transactions, American Geophysical Union, V. 74, no. 30, 337-338, 1993.

Hubbard, D.K., K.M. Parsons, J.D. Bythell and N.D. Walker, The effects of Hurricane Hugo on the reefs and associated environments of St. Croix, U.S. Virgin Islands - a preliminary assessment, Journal of Coastal Research, special issue no. 8: 33-48, 1991.

Walker, N.D. and F.A. Shillington, The effect of oceanographic variability on South African weather and climate, South African Journal of Science, 86:  382-386, 1990.

*Mey, R.D., N.D. Walker and M.R. Jury, Surface heat fluxes and marine boundary layer modification in the Agulhas Retroflection region during SCARC, Journal of Geophysical Research, 95:  15997-16015, 1990.

Shannon, L.V., J.J. Agenbag, N.D. Walker and J.R.E. Lutjeharms, A major perturbation in the Agulhas retroflection area in 1986, Deep Sea Research, 37, 493-512, 1990.

Walker, N.D., Links between South African summer rainfall and temperature variability of the Agulhas and Benguela Current systems, Journal of Geophysical Research, 95C, 3297-3319, 1990.

Walker, N.D. and J.A. Lindesay, Preliminary observations of oceanic influences on the February-March 1988 floods in central South Africa, South African Journal of Science, 85, 164-169, 1989.

Walker, N.D. and R.D. Mey, Ocean/atmosphere heat fluxes within the Agulhas Retroflection region, Journal of Geophysical Research, 93C, 15473-15483, 1988.

Jury, M. and N.D. Walker, Marine boundary layer modification across the edge of the Agulhas Current, Journal of Geophysical Research, 93C, 647-654, 1988.

Walker, N.D., L.J. Rouse, and O.K. Huh, 1987, Response of subtropical shallow-water environments to cold-air outbreak events: Satellite radiometry and heat flux modeling, Continental Shelf Research, 7, 735-757, 1987.

Walker, N.D., Interannual sea surface temperature variability and associated atmospheric forcing within the Benguela system, The Benguela and Comparable Ecosystems, South African Journal of Marine Science, 5 (special issue), Eds. Payne, A.I.L., J.A. Gulland, and K.H. Brink, 121-132, 1987.

Walker, N.D., Satellite observations of the Agulhas Current and episodic upwelling south of Africa, Deep Sea Research, 33, 1083-1106, 1986.

Nelson, G. and N.D. Walker, Comparison of summer winds on the west coast of South Africa between 1979 and 1983 and the response of coastal upwelling, South African Journal of Science, 80, 90-93, 1984.

Walker, N.D., J. Taunton-Clark and J.Pugh, Sea temperatures off the South African west coast as indicators of Benguela warm events, South African Journal of Science, 80, 72-77, 1984.

Gillooly, J.F. and N.D. Walker, Spatial and temporal behaviour of sea surface temperatures in the South Atlantic, South African Journal of Science, 80, 97-100, 1984.

Huh, O.K., L.J. Rouse, and N.D. Walker, Cold air outbreaks over the northwest Florida continental shelf: Heat flux processes and hydrographic changes, Journal of Geophysical Research, 89, 717-726, 1984.

Walker, N.D., H. Roberts, L. Rouse, and O.K. Huh, Thermal history of reef-associated environments during a record cold-air outbreak event, Coral Reefs, 1., no. 1, 83-87, 1982.

Roberts, H. H., L. J. Rouse, Jr., and N. D. Walker, Evolution of cold-water stress conditions in high-latitude reef systems: Florida Reef Tract and the Bahama Banks, Caribbean Journal of Science, v. 19, p. 55-60, 1982.

Roberts, H., L. Rouse, N. Walker and J. Hudson, Cold water stress in Florida Bay and northern Bahamas: A product of winter cold-air outbreaks, Journal of Sedimentary Petrology, 52, no. 1, 145-155, 1982.

73.  Walker, N.D., January water temperatures kill Florida fauna, Coastal Oceanography and Climatology News, 3, 1981.