Neil Kamal Ganju, PhD
My research spans the multiple disciplines that converge in estuarine systems. Research projects include numerical model development, field observations of hydrodynamics and water quality, wetland and coastal vulnerability assessments, geomorphic change, and eutrophication.
In 2001, I began working for the USGS at the California Water Science Center, on the San Francisco Bay Sediment Transport Project with Dr. David Schoellhamer. In 2008 I moved to the Woods Hole Coastal and Marine Science Center and began multiple projects throughout the northeast US. The Estuarine Processes, Hazards, and Ecosystems project, started in 2015, details the past and ongoing studies we are involved with.
Professional Experience
2010-present: Research Oceanographer, Woods Hole Coastal and Marine Science Center
2008-2010: Hydraulic Engineer, Woods Hole Coastal and Marine Science Center
2001-2008: Hydraulic Engineer, California Water Science Center
Education and Certifications
I studied civil engineering at the University of Michigan (BSCE), the University of Florida (MSCE), and the University of California-Davis (Ph.D.).
Science and Products
Filter Total Items: 19
Estuarine Processes Model Development
We are developing new routines within the COAWST model framework to represent coupled bio-physical processes in estuarine and coastal regions. These include routines for marsh vulnerability to waves, estuarine biogeochemistry, and feedbacks between aquatic vegetation and hydrodynamics.
Filter Total Items: 76
Geospatial characterization of salt marshes in Connecticut (ver. 2.0, April 2024) Geospatial characterization of salt marshes in Connecticut (ver. 2.0, April 2024)
This data release contains coastal wetland synthesis products for the state of Connecticut. Metrics for resiliency, including the unvegetated to vegetated ratio (UVVR), marsh elevation, tidal range, wave power, and exposure potential to environmental health stressors are calculated for smaller units delineated from a digital elevation model, providing the spatial variability of physical...
Lifespan of Massachusetts salt marsh units Lifespan of Massachusetts salt marsh units
Lifespan of salt marshes in Massachusetts (MA) are calculated using conceptual marsh units defined by Ackerman and others (2022). The lifespan calculation is based on estimated sediment supply and sea-level rise (SLR) predictions after Ganju and others (2020). Sea level predictions are local estimates which correspond to the 0.3, 0.5, and 1.0 meter increase in Global Mean Sea Level (GMSL...
Water quality data from a multiparameter sonde collected in the Herring River during November 2018 to November 2019 in Wellfleet, MA Water quality data from a multiparameter sonde collected in the Herring River during November 2018 to November 2019 in Wellfleet, MA
Management efforts of the tidally-restricted Herring River in Wellfleet, MA include research to understand pre-restoration sediment conditions. Submerged multiparameter sondes that measure optical turbidity were deployed at four sites landward and seaward of the Herring River restriction. Periodically, the sites were visited and additional turbidity measurements were collected with a...
Time-series measurements of oceanographic and water quality data collected in the Herring River, Wellfleet, Massachusetts, USA, November 2018 to November 2019 Time-series measurements of oceanographic and water quality data collected in the Herring River, Wellfleet, Massachusetts, USA, November 2018 to November 2019
Restoration in the tidally restricted Herring River Estuary in Wellfleet, MA benefits from understanding pre-restoration sediment transport conditions. Submerged sensors were deployed at four sites landward and seaward of the Herring River restriction to measure water velocity, water quality, water level, waves, and seabed elevation. These data will be used to evaluate sediment dynamics...
Aerial imagery and ground control points collected during an uncrewed aerial systems (UAS) survey at Plum Island Estuary and Parker River NWR (PIEPR), November 14, 2017 and March 28, 2019 Aerial imagery and ground control points collected during an uncrewed aerial systems (UAS) survey at Plum Island Estuary and Parker River NWR (PIEPR), November 14, 2017 and March 28, 2019
Low-altitude (80 and 100 meters above ground level) digital images were taken over an area of the Plum Island Estuary and Parker River National Wildlife Refuge (NWR) in Massachusetts using 3DR Solo unmanned aircraft systems (UAS) on November 14, 2017 and March 28, 2019. These images were collected as part of an effort to document marsh stability over time and quantify sediment movement...
Geospatial characterization of salt marshes on the Eastern Shore of Virginia Geospatial characterization of salt marshes on the Eastern Shore of Virginia
This data release contains coastal wetland synthesis products for the Atlantic-facing Eastern Shore of Virginia (the data release for the Chesapeake Bay-facing portion of the Eastern Shore of Virginia is found here: https://doi.org/10.5066/P997EJYB). Metrics for resiliency, including unvegetated to vegetated ratio (UVVR), marsh elevation, and tidal range are calculated for smaller units...
Filter Total Items: 121
Development and application of Landsat-based wetland vegetation cover and unvegetated-vegetated marsh ratio (UVVR) for the conterminous United States Development and application of Landsat-based wetland vegetation cover and unvegetated-vegetated marsh ratio (UVVR) for the conterminous United States
Effective management and restoration of salt marshes and other vegetated intertidal habitats require objective and spatially integrated metrics of geomorphic status and vulnerability. The unvegetated-vegetated marsh ratio (UVVR), a recently developed metric, can be used to establish present-day vegetative cover, identify stability thresholds, and quantify vulnerability to open-water...
Authors
Neil K. Ganju, Brady Couvillion, Zafer Defne, Kate Ackerman
Modeling the dynamics of salt marsh development in coastal land reclamation Modeling the dynamics of salt marsh development in coastal land reclamation
The valuable ecosystem services of salt marshes are spurring marsh restoration projects around the world. However, it is difficult to determine the final vegetated area based on physical drivers. Herein, we use a 3D fully coupled vegetation-hydrodynamic-morphological modeling system (COAWST), to simulate the final vegetation cover and the timescale to reach it under various forcing...
Authors
Yiyang Xu, Tarandeep S. Kalra, Neil K. Ganju, Sergio Fagherazzi
How much marsh restoration is enough to deliver wave attenuation coastal protection benefits? How much marsh restoration is enough to deliver wave attenuation coastal protection benefits?
As coastal communities grow more vulnerable to sea-level rise and increased storminess, communities have turned to nature-based solutions to bolster coastal resilience and protection. Marshes have significant wave attenuation properties and can play an important role in coastal protection for many communities. Many restoration projects seek to maximize this ecosystem service but how much...
Authors
Katherine A. Castagno, Neil K. Ganju, Michael W. Beck, Alison Bowden, Steven B. Scyphers
Modeling marsh dynamics using a 3-D coupled wave-flow-sediment model Modeling marsh dynamics using a 3-D coupled wave-flow-sediment model
Salt marshes are dynamic biogeomorphic systems that respond to external physical factors, including tides, sediment transport, and waves, as well as internal processes such as autochthonous soil formation. Predicting the fate of marshes requires a modeling framework that accounts for these processes in a coupled fashion. In this study, we implement two new marsh dynamic processes in the...
Authors
Tarandeep S. Kalra, Neil K. Ganju, Alfredo Aretxabaleta, Joel A. Carr, Zafer Defne, Julia Moriarty
Quantifying slopes as a driver of forest to marsh conversion using geospatial techniques: Application to Chesapeake Bay coastal-plain, USA Quantifying slopes as a driver of forest to marsh conversion using geospatial techniques: Application to Chesapeake Bay coastal-plain, USA
Coastal salt marshes, which provide valuable ecosystem services such as flood mitigation and carbon sequestration, are threatened by rising sea level. In response, these ecosystems migrate landward, converting available upland into salt marsh. In the coastal-plain surrounding Chesapeake Bay, United States, conversion of coastal forest to salt marsh is well-documented and may offset salt...
Authors
Grace Damore Molino, Zafer Defne, Alfredo Aretxabaleta, Neil K. Ganju, Joel A. Carr
Sediment dynamics of a divergent bay–marsh complex Sediment dynamics of a divergent bay–marsh complex
Bay–marsh systems, composed of an embayment surrounded by fringing marsh incised by tidal channels, are widely distributed coastal environments. External sediment availability, marsh-edge erosion, and sea-level rise acting on such bay–marsh complexes may drive diverse sediment-flux regimes. These factors reinforce the ephemeral and dynamic nature of fringing marshes: material released by...
Authors
Daniel J. Nowacki, Neil K. Ganju
Non-USGS Publications**
Defne, Z., N. K. Ganju, and A. Aretxabaleta
(2016), Estimating time-dependent
connectivity in marine systems, Geophys.
Res. Lett., 43, doi:10.1002/2015GL066888.
(2016), Estimating time-dependent
connectivity in marine systems, Geophys.
Res. Lett., 43, doi:10.1002/2015GL066888.
Ganju, N. K., Brush, M. J., Rashleigh, B., Aretxabaleta, A. L., del Barrio, P., Grear, J. S., ... & Vaudrey, J. M., 2015, Progress and challenges in coupled hydrodynamic-ecological estuarine modeling, Estuaries and Coasts, 1-22.
Ganju, N.K., Jaffe, B.E., and Schoellhamer, D.H., 2011, Discontinuous hindcast simulations of estuarine bathymetric change: a case study from Suisun Bay, California. Estuarine, Coastal and Shelf Science, 93, 142-150.
Ganju, N.K., and Schoellhamer, D.H., 2006, Annual sediment flux estimates in a tidal strait using surrogate measurements. Estuarine, Coastal and Shelf Science, 69, 165-178.
Ganju, N.K., Schoellhamer, D.H., and Jaffe, B.E., 2009, Hindcasting of decadal-timescale estuarine bathymetric change with a tidal-timescale model. Journal of Geophysical Research-Earth Surface, 114, F04019, doi:10.1029/2008JF001191.
Ganju, N.K., Schoellhamer, D.H., Warner, J.C., Barad, M.F., and Schladow, S.G., 2004, Tidal oscillation of sediment between a river and a bay: a conceptual model. Estuarine, Coastal and Shelf Science, 60(1), 81-90.
Ganju, N.K., and Sherwood, C.R., 2010, Effect of roughness formulation on the performance of a coupled wave, hydrodynamic, and sediment transport model. Ocean Modelling, 33, 299-313.
Gartner, J.W., and Ganju, N.K., 2007, Correcting acoustic Doppler current profiler discharge measurement bias from moving-bed conditions without global positioning during the 2004 Glen Canyon Dam controlled flood on the Colorado River. Limnology and Oceanography: Methods, 5, 156-162.
Leonardi, N., Ganju, N.K. and Fagherazzi, S., 2016. A linear relationship between wave power and erosion determines salt-marsh resilience to violent storms and hurricanes. Proceedings of the National Academy of Sciences, 113(1), pp.64-68.
Kirincich, A. R., Lentz, S. J., Farrar, J. T., and Ganju, N. K., 2013, The Spatial Structure of Tidal and Mean Circulation over the Inner Shelf South of Martha's Vineyard, Massachusetts. Journal of Physical Oceanography, 43(9).
Miselis, J.L., Andrews, B.D., Nicholson, R.S., Defne, Z., Ganju, N.K. and Navoy, A., 2015. Evolution of mid-Atlantic coastal and back-barrier estuary environments in response to a hurricane: Implications for barrier-estuary connectivity. Estuaries and Coasts, pp.1-19.
Oestreich, W. K., Ganju, N. K., Pohlman, J. W., and Suttles, S. E., 2016. Colored dissolved organic matter in shallow estuaries: relationships between carbon sources and light attenuation, Biogeosciences, 13, 583-595, doi:10.5194/bg-13-583-2016.
Rosencranz, J.A., Ganju, N.K., Ambrose, R.F., Brosnahan, S.M., Dickhudt, P.J., Guntenspergen, G.R., MacDonald, G.M., Takekawa, J.Y, and Thorne, K.M., 2015, Balanced sediment fluxes in southern California’s Mediterranean-climate zone salt marshes, Estuaries and Coasts, DOI 10.1007/s12237-015-0056-y.
**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
Filter Total Items: 19
Estuarine Processes Model Development
We are developing new routines within the COAWST model framework to represent coupled bio-physical processes in estuarine and coastal regions. These include routines for marsh vulnerability to waves, estuarine biogeochemistry, and feedbacks between aquatic vegetation and hydrodynamics.
Filter Total Items: 76
Geospatial characterization of salt marshes in Connecticut (ver. 2.0, April 2024) Geospatial characterization of salt marshes in Connecticut (ver. 2.0, April 2024)
This data release contains coastal wetland synthesis products for the state of Connecticut. Metrics for resiliency, including the unvegetated to vegetated ratio (UVVR), marsh elevation, tidal range, wave power, and exposure potential to environmental health stressors are calculated for smaller units delineated from a digital elevation model, providing the spatial variability of physical...
Lifespan of Massachusetts salt marsh units Lifespan of Massachusetts salt marsh units
Lifespan of salt marshes in Massachusetts (MA) are calculated using conceptual marsh units defined by Ackerman and others (2022). The lifespan calculation is based on estimated sediment supply and sea-level rise (SLR) predictions after Ganju and others (2020). Sea level predictions are local estimates which correspond to the 0.3, 0.5, and 1.0 meter increase in Global Mean Sea Level (GMSL...
Water quality data from a multiparameter sonde collected in the Herring River during November 2018 to November 2019 in Wellfleet, MA Water quality data from a multiparameter sonde collected in the Herring River during November 2018 to November 2019 in Wellfleet, MA
Management efforts of the tidally-restricted Herring River in Wellfleet, MA include research to understand pre-restoration sediment conditions. Submerged multiparameter sondes that measure optical turbidity were deployed at four sites landward and seaward of the Herring River restriction. Periodically, the sites were visited and additional turbidity measurements were collected with a...
Time-series measurements of oceanographic and water quality data collected in the Herring River, Wellfleet, Massachusetts, USA, November 2018 to November 2019 Time-series measurements of oceanographic and water quality data collected in the Herring River, Wellfleet, Massachusetts, USA, November 2018 to November 2019
Restoration in the tidally restricted Herring River Estuary in Wellfleet, MA benefits from understanding pre-restoration sediment transport conditions. Submerged sensors were deployed at four sites landward and seaward of the Herring River restriction to measure water velocity, water quality, water level, waves, and seabed elevation. These data will be used to evaluate sediment dynamics...
Aerial imagery and ground control points collected during an uncrewed aerial systems (UAS) survey at Plum Island Estuary and Parker River NWR (PIEPR), November 14, 2017 and March 28, 2019 Aerial imagery and ground control points collected during an uncrewed aerial systems (UAS) survey at Plum Island Estuary and Parker River NWR (PIEPR), November 14, 2017 and March 28, 2019
Low-altitude (80 and 100 meters above ground level) digital images were taken over an area of the Plum Island Estuary and Parker River National Wildlife Refuge (NWR) in Massachusetts using 3DR Solo unmanned aircraft systems (UAS) on November 14, 2017 and March 28, 2019. These images were collected as part of an effort to document marsh stability over time and quantify sediment movement...
Geospatial characterization of salt marshes on the Eastern Shore of Virginia Geospatial characterization of salt marshes on the Eastern Shore of Virginia
This data release contains coastal wetland synthesis products for the Atlantic-facing Eastern Shore of Virginia (the data release for the Chesapeake Bay-facing portion of the Eastern Shore of Virginia is found here: https://doi.org/10.5066/P997EJYB). Metrics for resiliency, including unvegetated to vegetated ratio (UVVR), marsh elevation, and tidal range are calculated for smaller units...
Filter Total Items: 121
Development and application of Landsat-based wetland vegetation cover and unvegetated-vegetated marsh ratio (UVVR) for the conterminous United States Development and application of Landsat-based wetland vegetation cover and unvegetated-vegetated marsh ratio (UVVR) for the conterminous United States
Effective management and restoration of salt marshes and other vegetated intertidal habitats require objective and spatially integrated metrics of geomorphic status and vulnerability. The unvegetated-vegetated marsh ratio (UVVR), a recently developed metric, can be used to establish present-day vegetative cover, identify stability thresholds, and quantify vulnerability to open-water...
Authors
Neil K. Ganju, Brady Couvillion, Zafer Defne, Kate Ackerman
Modeling the dynamics of salt marsh development in coastal land reclamation Modeling the dynamics of salt marsh development in coastal land reclamation
The valuable ecosystem services of salt marshes are spurring marsh restoration projects around the world. However, it is difficult to determine the final vegetated area based on physical drivers. Herein, we use a 3D fully coupled vegetation-hydrodynamic-morphological modeling system (COAWST), to simulate the final vegetation cover and the timescale to reach it under various forcing...
Authors
Yiyang Xu, Tarandeep S. Kalra, Neil K. Ganju, Sergio Fagherazzi
How much marsh restoration is enough to deliver wave attenuation coastal protection benefits? How much marsh restoration is enough to deliver wave attenuation coastal protection benefits?
As coastal communities grow more vulnerable to sea-level rise and increased storminess, communities have turned to nature-based solutions to bolster coastal resilience and protection. Marshes have significant wave attenuation properties and can play an important role in coastal protection for many communities. Many restoration projects seek to maximize this ecosystem service but how much...
Authors
Katherine A. Castagno, Neil K. Ganju, Michael W. Beck, Alison Bowden, Steven B. Scyphers
Modeling marsh dynamics using a 3-D coupled wave-flow-sediment model Modeling marsh dynamics using a 3-D coupled wave-flow-sediment model
Salt marshes are dynamic biogeomorphic systems that respond to external physical factors, including tides, sediment transport, and waves, as well as internal processes such as autochthonous soil formation. Predicting the fate of marshes requires a modeling framework that accounts for these processes in a coupled fashion. In this study, we implement two new marsh dynamic processes in the...
Authors
Tarandeep S. Kalra, Neil K. Ganju, Alfredo Aretxabaleta, Joel A. Carr, Zafer Defne, Julia Moriarty
Quantifying slopes as a driver of forest to marsh conversion using geospatial techniques: Application to Chesapeake Bay coastal-plain, USA Quantifying slopes as a driver of forest to marsh conversion using geospatial techniques: Application to Chesapeake Bay coastal-plain, USA
Coastal salt marshes, which provide valuable ecosystem services such as flood mitigation and carbon sequestration, are threatened by rising sea level. In response, these ecosystems migrate landward, converting available upland into salt marsh. In the coastal-plain surrounding Chesapeake Bay, United States, conversion of coastal forest to salt marsh is well-documented and may offset salt...
Authors
Grace Damore Molino, Zafer Defne, Alfredo Aretxabaleta, Neil K. Ganju, Joel A. Carr
Sediment dynamics of a divergent bay–marsh complex Sediment dynamics of a divergent bay–marsh complex
Bay–marsh systems, composed of an embayment surrounded by fringing marsh incised by tidal channels, are widely distributed coastal environments. External sediment availability, marsh-edge erosion, and sea-level rise acting on such bay–marsh complexes may drive diverse sediment-flux regimes. These factors reinforce the ephemeral and dynamic nature of fringing marshes: material released by...
Authors
Daniel J. Nowacki, Neil K. Ganju
Non-USGS Publications**
Defne, Z., N. K. Ganju, and A. Aretxabaleta
(2016), Estimating time-dependent
connectivity in marine systems, Geophys.
Res. Lett., 43, doi:10.1002/2015GL066888.
(2016), Estimating time-dependent
connectivity in marine systems, Geophys.
Res. Lett., 43, doi:10.1002/2015GL066888.
Ganju, N. K., Brush, M. J., Rashleigh, B., Aretxabaleta, A. L., del Barrio, P., Grear, J. S., ... & Vaudrey, J. M., 2015, Progress and challenges in coupled hydrodynamic-ecological estuarine modeling, Estuaries and Coasts, 1-22.
Ganju, N.K., Jaffe, B.E., and Schoellhamer, D.H., 2011, Discontinuous hindcast simulations of estuarine bathymetric change: a case study from Suisun Bay, California. Estuarine, Coastal and Shelf Science, 93, 142-150.
Ganju, N.K., and Schoellhamer, D.H., 2006, Annual sediment flux estimates in a tidal strait using surrogate measurements. Estuarine, Coastal and Shelf Science, 69, 165-178.
Ganju, N.K., Schoellhamer, D.H., and Jaffe, B.E., 2009, Hindcasting of decadal-timescale estuarine bathymetric change with a tidal-timescale model. Journal of Geophysical Research-Earth Surface, 114, F04019, doi:10.1029/2008JF001191.
Ganju, N.K., Schoellhamer, D.H., Warner, J.C., Barad, M.F., and Schladow, S.G., 2004, Tidal oscillation of sediment between a river and a bay: a conceptual model. Estuarine, Coastal and Shelf Science, 60(1), 81-90.
Ganju, N.K., and Sherwood, C.R., 2010, Effect of roughness formulation on the performance of a coupled wave, hydrodynamic, and sediment transport model. Ocean Modelling, 33, 299-313.
Gartner, J.W., and Ganju, N.K., 2007, Correcting acoustic Doppler current profiler discharge measurement bias from moving-bed conditions without global positioning during the 2004 Glen Canyon Dam controlled flood on the Colorado River. Limnology and Oceanography: Methods, 5, 156-162.
Leonardi, N., Ganju, N.K. and Fagherazzi, S., 2016. A linear relationship between wave power and erosion determines salt-marsh resilience to violent storms and hurricanes. Proceedings of the National Academy of Sciences, 113(1), pp.64-68.
Kirincich, A. R., Lentz, S. J., Farrar, J. T., and Ganju, N. K., 2013, The Spatial Structure of Tidal and Mean Circulation over the Inner Shelf South of Martha's Vineyard, Massachusetts. Journal of Physical Oceanography, 43(9).
Miselis, J.L., Andrews, B.D., Nicholson, R.S., Defne, Z., Ganju, N.K. and Navoy, A., 2015. Evolution of mid-Atlantic coastal and back-barrier estuary environments in response to a hurricane: Implications for barrier-estuary connectivity. Estuaries and Coasts, pp.1-19.
Oestreich, W. K., Ganju, N. K., Pohlman, J. W., and Suttles, S. E., 2016. Colored dissolved organic matter in shallow estuaries: relationships between carbon sources and light attenuation, Biogeosciences, 13, 583-595, doi:10.5194/bg-13-583-2016.
Rosencranz, J.A., Ganju, N.K., Ambrose, R.F., Brosnahan, S.M., Dickhudt, P.J., Guntenspergen, G.R., MacDonald, G.M., Takekawa, J.Y, and Thorne, K.M., 2015, Balanced sediment fluxes in southern California’s Mediterranean-climate zone salt marshes, Estuaries and Coasts, DOI 10.1007/s12237-015-0056-y.
**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.