Judith Drexler, Ph.D.



Ph.D., Natural Resouces, Cornell University

M.A. Geography, University of Colorado, Boulder

B.A. Enivronmental Science, University of California, Berkeley


My work is focused on carbon storage, wetland formation, and invasive aquatic vegetation impacts on ecosystem processes.  In addiiton, I am interested in the impact of various types of disturbance, including nutrient loading, hydrologic alteration, and climate change, on the sustainability of wetland systems.  Through the years, I have worked in a variety of ecosystem types including peatlands along the east coast, Micronesian mangroves and freshwater swamps, tidal marshes in the San Francisco Estuary and Pacific northwest, and montane fens of the Sierra Nevada.  


I have been with the federal government for over twenty years.  I started out at the US EPA after college and then worked with the USDA Forest Service as a postdoc in Honolulu, HI from 1997-1999.  I have been at the US Geological Survey, California Water Science Center since 2000 working as a hydrologist/wetland ecologist. 


Journal articles and book chapters:

Drexler, J.Z., Khanna, S., Schoellhamer, D.H., and Orlando, J. 2019. The Fate of Blue Carbon in the Sacramento-San Joaquin Delta of California, USA. In: A Blue Carbon Primer: The State of Coastal Wetland Carbon Science, Practice, and Policy, Windham-Myers, L., Crooks, S. and Troxler, T. (eds.), CRC Press, Boca Raton, FL.

Kolka, R., C. Trettin, W. Tang, K. Krauss, S. Bansal, J. Drexler, K. Wickland, R. Chimner, D. Hogan, E. J. Pindilli, B. Benscoter, B. Tangen, E. Kane, S. Bridgham, and C. Richardson. 2018. Chapter 13: Terrestrial wetlands. In Second State of the Carbon Cycle Report (SOCCR2): A Sustained Assessment Report. [Cavallaro, N., G. Shrestha, R. Birdsey, M. A. Mayes, R. G. Najjar, S. C. Reed, P. Romero-Lankao, and Z. Zhu (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, pp. 507-567, https://doi.org/10.7930/S.

Drexler, J.Z. and Fuller, C.C. 2018. The approaching obsolescence of 137Cs as a means of dating wetland soils and sediments in North America, Quaternary Science Reviews 199: 83-96; DOI:10.1016/j.quascirev.2018.08.028.

Holmquist, J.R., Windham-Myers, L., Bliss, N., Crooks, S., Morris, J., Megonigal, J.P., Troxler, T., Weller, D., Callaway, J., Drexler, J.Z., Ferner, M.C., Gonneea, M.E., Kroeger, K.D., Schile-Beers, L., Woo, I., Buffington, K.,  Boyd, B.M., Breithaupt, J., Brown, L.N., Dix, N., Hice, L., Horton, B.P., MacDonald, G.M., Moyer, R.P., Reay, W., Shaw, T., Smith, E., Smoak, J.M., Sommerfield, C., Thorne, K., Velinsky, D., Watson, E., Wilson Grimes, K., and Woodrey, M. 2018. Accuracy and Precision of Tidal Wetlands Soil Carbon Mapping in the Conterminous United States. Scientific Reports 8:1-16; DOI:10.1038/s41598-018-26948-7.

Drexler, J.Z., Fuller, C.C., Orlando, J., Salas, A., Wurster, F.C., and Duberstein, J.A. 2017. Estimation and uncertainty of recent carbon accumulation and vertical accretion in drained and undrained forested peatlands of the southeastern USA. Journal of Geophysical ResearchBiogeosciences, published online: DOI:10.1002/2017JG003950.

Cloern, J.E., Robinson, A., Richey, A., Grenier, G., Grossinger, R., Boyer, K., Burau, J., Canuel, E., DeGeorges, J., Drexler, J., Enright, C., Howes, E., Kneib, E., Mueller-Solger, A., Naimans, R., Pinckney, J., Safran, S., Schoellhamer, D., and Simenstad, C. 2016.  Primary Production in the Delta: Then and Now. San Francisco Estuary and Watershed Science, 14(3). jmie_sfews_32799. Retrieved from: http://escholarship.org/uc/item/8fq0n5gx.

Drexler, J.Z., Alpers, C.N., Neymark, L.A., Paces, J.B., Taylor, J.B. and Fuller, C.C. 2016. A millennial-scale record of Pb and Hg contamination in peatlands of the Sacramento–San Joaquin Delta of California, USA. Science of the Total Environment 551–552:738–751.

Anderson, F.E., Bergamaschi, B., Sturtevant, C., Knox, S., Hastings, L., Windham-Myers, L., Detto, M., Drexler, J.Z., Miller, R.L., Matthes, J.H., Verfaillie, J., Baldocchi, D., Snyder, R.L., and R. Fujii. 2016. Variation of energy and carbon fluxes from a restored temperate freshwater wetland and implications for carbon market verification protocols. Journal of Geophysical Research: Biogeosiences DOI: 10.1002/2015JG003083.

Drexler, J.Z., Fuller, C.C., Orlando, J., and Moore, P. 2015. Recent rates of carbon accumulation in montane fens of Yosemite National Park, California, USA. Arctic, Antarctic, and Alpine Research 47:657-669.

Swanson, K., Drexler, J.Z., Fuller, C.C., and Schoellhamer, D.H. 2015. Future sustainability of tidal freshwater marshes in the Sacramento-San Joaquin Delta of California under multiple scenarios of sea-level rise and sediment availability. San Francisco Estuary and Watershed Science 13(1), https://escholarship.org/uc/item/9h8197nt.

Deverel. S.J., Ingrum, T., Hart, C, and Drexler J.Z. 2014. Impounded marshes on subsided islands: simulated vertical accretion, processes, and effects, Sacramento-San Joaquin Delta, CA USA. San Francisco Estuary and Watershed Science, published online at https://escholarship.org/uc/item/0qm0w92c.   

Drexler, J.Z., Johnson, H.E., Duris, J., and Krauss, K. 2014. Marsh soils as potential sinks for Bacteroides fecal indicator bacteria, Waccamaw National Wildlife Refuge, Georgetown, South Carolina, USA. Water, Air, & Soil Pollution 225: 1861-1867.

Drexler, J.Z., Paces, J., Alpers, C.N., Windham-Myers, L., Neymark, L., and Taylor, H.E. 2013c. 234U/238U and 87Sr in peat as useful tracers of paleosalinity in the Sacramento-San Joaquin Delta of California. Applied Geochemistry 40: 164-179.

Swanson, K., Drexler, J.Z., Schoellhamer, D., Takekawa, J., Thorne, K., Spragens, K., Casazza, M., Overton, C., and Callaway, J. 2013. The wetland accretion rate model of ecosystem resilience (WARMER) and its application to questions of habitat sustainability in the San Francisco Estuary. Estuaries and Coasts 37(2): 476-492.

Drexler, J.Z., Krauss, K.W., Sasser, M.C., Fuller, C.C., Swarzenski, C.M., Powell, A., Swanson, K.M., and Orlando, J. 2013. A long-term comparison of carbon sequestration rates in impounded and naturally tidal freshwater marshes along the lower Waccamaw River, South Carolina. Wetlands 33(5): 965-974.

Schoellhamer, D.H., Wright, S.A., and Drexler, J.Z. 2013. Adjustment of the San Francisco estuary and watershed to reducing sediment supply in the 20th century. Marine Geology 345: 63-71.

Drexler, J.Z., Knifong, D., Tuil, J., Flint, L, and Flint, A. 2013. Fens as whole-ecosystem gauges of groundwater recharge under climate change. Journal of Hydrology 481: 22-34.

Schoellhamer, D.H., Wright, S.A., and Drexler, J.Z. 2012. Conceptual Model of Sedimentation in the Sacramento – San Joaquin River Delta. San Francisco Estuary and Watershed Science 10(3), 25 p., http://www.escholarship.org/uc/jmie_sfews.

Drexler, J.Z. 2011. Peat formation processes through the millennia in marshes of the Sacramento-San Joaquin Delta, CA, USA. Estuaries and Coasts 34: 900–911.  

Drexler, J.Z., de Fontaine, C.S., and Thomas A. Brown. 2009b. Peat accretion histories during the past 6,000 years in               marshes of the Sacramento-San Joaquin Delta of California, USA. Estuaries and Coasts 32: 871-892.

Drexler, J.Z., de Fontaine, C.S., and Deverel, S.J. 2009a. The legacy of wetland drainage on the peat resource in the Sacramento – San Joaquin Delta, CA, USA. Wetlands 29(1): 372-386.

Drexler, J.Z., Snyder, R.L., and Anderson, F.E. 2008. Evapotranspiration rates and crop coefficients for a restored marsh in the Sacramento-San Joaquin Delta, California, USA. Hydrological Processes 22: 725-735.   

Drexler, J.Z., Snyder, R.L., Spano, D., and Paw U, K.T. 2004. A review of models and methods to estimate wetland evapotranspiration.  Hydrological Processes 18(11): 2071-2101.

Anderson, F.E., Snyder, R.L., Miller, R.L., and Drexler, J.Z. 2003. A micrometeorological investigation of a restored California wetland ecosystem. Bulletin of the American Meteorological Society, September 2003.

Drexler, J.Z. and Bedford, B.L.  2002. Pathways of Nutrient Loading and Impacts on Plant Diversity in a New York Peatland.  Wetlands 22(2): 263-281.

Drexler, J.Z. and De Carlo, E.  2002. Source water partitioning as a mean of characterizing hydrologic function of mangroves. Wetlands Ecology and Management 10(2): 103-113.

Drexler, J.Z. and Ewel, K.C. 2001. Effects of ENSO-related drought on hydrology and salinity in a Micronesian wetland complex. Estuaries 24(3): 347-356.

Drexler, J.Z. 2001. Maximum longevities of Rhizophora apiculata and R. mucronata propagules. Pacific Science 55(1): 17-22.

Drexler, J.Z., Bedford, B.L., Scognamiglio, R., and Siegel, D.I. 1999. Fine-scale characteristics of groundwater flow in a peatland. Hydrological Processes 13: 1341-1359.

Drexler, J.Z., Bedford, B.L., DeGaetano, A., and Siegel, D.I. 1999. Quantification of the water budget and nutrient loading for a small peatland in central New York. Journal of the American Water Resources Association 34(4): 753-769.

Other reports:

Orlando, J. and Drexler, J.Z. 2017. Factors affecting marsh vegetation at the Liberty Island Conservation Bank in the Cache Slough region of the Sacramento-San Joaquin Delta, California, 2017. U.S. Geological Survey Open-File Report 2017-1077, 25pp., https://doi.org/10.3133/ofr20171077.

Anderson, F., Bergamaschi, B., Windham-Myers, L., Woo, I., De La Cruz, S., Drexler, J.Z., Byrd, K., and Thorne, K. 2016, Assessing wildlife benefits and carbon from restored and natural coastal marshes in the Nisqually River delta: Determining marsh net ecosystem carbon balance: U.S. Geological Survey Fact Sheet 2016-3042, 2 p.

Robinson, A., Richey, A., Cloern, J.E., Boyer, K.E., Bureau, J., Canuel, E., DeGeorge, J., Drexler, J.Z., Grenier, L., Grossinger, R.L., Howe, E.R., Kneib, R., Naiman, R.J., Mueller-Solger, A., Pinckney, J.L., Schoellhamer, D., and Simenstad, C. 2016. Primary production in the Sacramento-San Joaquin Delta: A science strategy to quantify change and identify future potential. Prepared with funding from the US Geological Survey and the Delta Science Program. A report of the SFEI-ASC’s Resilient Landscapes Program, Publication #781, San Francisco Estuary Institute-Aquatic Science Center, Richmond, CA.

Drexler, J.Z.  2015. Entries for “blue carbon”, “carbon sequestration, “marsh drowning, and “tidal freshwater habitat”. In:  Encyclopedia of Estuaries, Kennish, M.J. (ed.); part of Encyclopedia of Earth Sciences Series, Springer.

Goals Project. 2015. The Baylands and Climate Change: What We Can Do. Baylands Ecosystem Habitat Goals Science Update 2015 prepared by the San Francisco Bay Area Wetlands Ecosystem Goals Project: California State Coastal Conservancy, Oakland, CA. Callaway, J.C., Crooks, S. Baldochhi, D., Chappell, E., Deverel, S., Drexler, J.Z., Grenier L., Miller, R., and Windham-Myers, L. Carbon sequestration and greenhouse gases in the Baylands, pp. 86-92.

Drexler, J.Z. 2013. Alpine wetlands as sentinels of climate change.  CIRMOUNT newsletter, spring 2013.

Takekawa, J.Y., Thorne, K.M., Buffington, K.J., Spragens, K., Swanson, K., Drexler J., Schoellhamer, D., Overton, C.T, Casazza M.L., and Gustafson, K. B. 2012. Final report for sea-level rise response modeling for San Francisco Bay Estuary tidal marshes. U. S Geological Survey, Western Ecological Research Center, Vallejo and Dixon, CA. [Digital Media]

Schoellhamer, D., Wright, S., Drexler, J.Z., Stacey, M. Sedimentation Conceptual Model.  2007. White Paper for the California Bay/Delta Science Program.

Drexler, J.Z., de Fontaine, C.S., and Knifong, D.L. 2007. Age determination of the remaining peat in the Sacramento-San Joaquin Delta, California, USA. U.S. Geological Survey Open-File Report 2007-1303.

Kerr, B.D., Wang, B., and Drexler, J.Z. 2003. Carbon fluxes, water levels, and related environmental data, Twitchell Island, Sacramento-San Joaquin Delta, California, November 1992 through September 1995. U.S. Geological Survey Open-File Report 03-370.

Gamble, J.M., Burow, K.R., Wheeler, G.A., Hilditch, R. and Drexler, J.Z. 2003. Hydrogeologic data from a shallow flooding demonstration project, Twitchell Island, California, 1997-2001. U.S. Geological Survey Open File Report 03-378.