Professor, Department of Geography & Interdepartmental Graduate Program in Marine Science
Director, Institute for Computational Earth System Science

Director, SPOT at UCSB
University of California, Santa Barbara

E-mail: davey @ icess.ucsb.edu

Phone: 01-805-893-4547

Mail: Institute for Computational Earth System Science, University of California, Santa Barbara, CA 93106-3060, USA

Research Interests:

Interdisciplinary marine science.  Coupling of physical, biological, optical and biogeochemical processes on micro to ocean basin scales. Specifically, ocean color remote sensing and optical oceanography, mesoscale eddy & coastal processes, numerical modeling, Lagrangian approaches to understanding mixing and its implications, quantification of subgrid scale processes, human-natural system coupling, role of radiative exchanges in air-sea interactions and data information systems.

My Research Projects:

I am lucky to have a variety of funded projects I am working on (due largely to the good graces of NASA and NSF).  Some of these projects I lead while others I am a contributor.  They all have the possibility of involvement of graduate and undergraduate students. Many of the bio-optically related projects I do in collaboration with Stephane Maritorena and Norm Nelson both are at UCSB ICESS. 


Projects with reasonable webpages include:

Global Analyses of Ocean Color Variability - This work focuses on analyzing time/space trends in global ocean color satellite data sets including the merging of available satellite data sets (merged data set site).  This work is done in collaboration with Stephane Maritorena, Norm Nelson, Mike Behrenfeld (OSU), Toby Westberry (OSU) and Jorge Sarmiento (Princeton). A cute article on our recent Nature paper (and me) can be accessed here

Global CDOM - Global surveying & characterization of the chromophoric dissolved organic matter pool as part of the CLIVAR Repeat Hydrography Survey - NSF / NASA - with Norm Nelson and Craig Carlson

Plumes and Blooms (PnB) - Ocean color investigations of the Santa Barbara Channel - NASA - with Stephane Maritorena

Kelp Remote Sensing using SPOT Imagery - New work using SPOT multispectral imagery to assess the dynamics of kelp forests in the northern Southern California Bight - Couples to the SCB-LTER below.  NASA - with Stephane Maritorena, Steve Gaines, Phaedon Kyriakidis, Brian Kinlan & Dick Zimmerman (ODU)

Flow, Fish & Fishing (F3) - Modeling project to assess the role of uncertainty in fishery management patterned after the nearshore fisheries of California - NSF - with Chris Costello, Steve Gaines, Ray Hilborn, Bruce Kendall, Steve Polasky, Bob Warner and Kraig Winters

Bermuda BioOptics Project (BBOP) - Ocean color investigations of the Sargasso Sea - NASA - Led by Norm Nelson

Santa Barbara Coastal Long-Term Ecological Research site (SBC-LTER) - Focuses on the drivers of change in kelp ecosystem off Santa Barbara - Led by Dan Reed

Eddies Dynamics, Mixing, Export and Species composition (EDDIES) - Field / satellite data effort to assess the importance of mesoscale eddies to the biogeochemistry of the Sargasso Sea - NSF - Led by Dennis McGillicuddy (WHOI)

Vertical Transport in the Global Ocean (VERTIGO) - Field effort to analyze the export of particulate carbon from the upper ocean and its cycling in the mesopelagic - NSF/DOE - Led by Ken Buesseler (WHOI)

SPOT - Provides deeply discounted SPOT imagery of US and Canada to other US universities (www.spot.ucsb.edu). The program also provides nearly free SPOT imagery to UCSB researchers and students (www.icess.ucsb.edu).  I am the director of the center.  


My Teaching:

I have a 1/2 time teaching release due to my administrative obligations to ICESS.  The following are courses that I find myself teaching often. Geog 210a is for incoming graduate students and Geog 163 and 158 are undergraduate offerings. I also teach graduate offerings in advanced physical oceanography, ocean color remote sensing and ocean optics when the demand is there.   


Geog 210a: Analytical Methods for Geography Research

Introduction to analytical methods used to geography research problems. Topics include: calculus, vector analysis, and differential equations. Emphasis is placed on problem statements and solutions.

I end up teaching this every fall. Syllabus is available here


Geog 163: Ocean Circulation

Examination of the general circulation of the oceans and its impact on global climate and climate change. Topics covered include the properties of seawater, the forces driving ocean currents, the wind and buoyancy generation of basin scale circulations and their impact on global climate.

I teach this every other year usually in the spring.  Class web site is available here


Geog 158: California Current

Introduction to the marine resources off the California coast. The interplay of oceanographic, climatic, biogeochemical and geologic factors and the influences of man will be addressed. Topics will include: climate, circulation, biogeography, fisheries, marine mammals, petroleum, pollution and exploration history.

I teach this every other year (and will teach it spring of 2007).  Class web site is available here


Selected Publications:

In press:

Siegel, D.A.., D.B. Court, D.W. Menzies, P. Peterson, S. Maritorena and N.B. Nelson, 2008: Satellite and in situ observations of the bio-optical signatures of two mesoscale eddies in the Sargasso Sea.  Deep-Sea Research Part II, in press [pdf]

Westberry, T.K., M.J. Behrenfeld, D.A. Siegel and E. Boss, 2008: Carbon-based primary productivity modeling with vertically resolved photoacclimation. Global Biogeochemical Cycles, in press [pdf]

Toole, D.A., D.A. Siegel and S.C. Doney, 2008: A light-driven, one-dimensional dimethylsulfide biogeochemical cycling model for the Sargasso Sea. Journal of Geophysical Research, Biogeosciences, in press [pdf]

Anderson, C.A.., D.A. Siegel, M.A. Brzezinski, N. Guillocheau, 2008: Controls on Temporal Patterns in Phytoplankton Community Structure in the Santa Barbara Channel, California.  Journal of Geophysical Research, Oceans, in press [pdf]

White, C. B.E. Kendall, S.D. Gaines, D.A. Siegel and C.J. Costello, 2008: Marine reserve effects on fishery profit. Ecology Letters, in press [pdf]

Siegel, D.A., S. Mitarai, C.J. Costello, S.D. Gaines, B.E. Kendall, R.R. Warner and K.B. Winters, 2008: Scales of connectivity among nearshore marine populations: The stochastic nature of larval transport. Proceedings of the National Academy of Science, in press [pdf]



Mitarai, S., D.A. Siegel and K.B. Winters, 2008: A numerical study of stochastic larval settlement in the California Current System. Journal of Marine Systems, 69, 295-309. [pdf]

Siegel, D.A.., E. Fields, and K.O. Buesseler, 2008: A bottom-up view of the biological pump: Modeling source funnels above ocean sediment traps.  Deep-Sea Research Part I, 55, 108-127 [pdf]



Kostadinov, T.S., D.A. Siegel, S. Maritorena, N. Guillocheau, 2007: Ocean color observations and modeling for an optically complex site: Santa Barbara Channel, California, USA.  Journal of Geophysical Research, Oceans, 112, C07011, 10.1029/2006JC003526 [pdf]

McPhee-Shaw, E.E., D.A. Siegel, L. Washburn , M.A. Brzezinski, J.L. Jones, A. Leydecker and J.M. Melack, 2007: Mechanisms for nutrient delivery to the inner shelf: Observations from the Santa Barbara Channel. Limnology and Oceanography, 52, 1748–1766. [pdf]

Nelson, N.B., D.A. Siegel, C.A. Carlson, C. Swan, W.M. Smethie, Jr., and S. Khatiwala, 2007: Hydrography of chromophoric dissolved organic matter in the North AtlanticDeep-Sea Research, Part I, 54, 710-731. [pdf]

McGillicuddy Jr., D.J. L.A. Anderson, N.R. Bates, T. Bibby, K.O. Buesseler, C.A. Carlson, C.S. Davis, C. Ewart, P.G. Falkowski, S.A. Goldthwait, D.A. Hansell, W.J. Jenkins, R. Johnson, V.K. Kosnyrev, J.R. Ledwell, Q.P. Li, D.A. Siegel, D.K. Steinberg, 2007: Eddy/wind interactions stimulate extraordinary mid-ocean plankton blooms. Science, 316, 1021-1026. [pdf] [supplementary info]

Buesseler, K.O., C.H. Lamborg, P.W. Boyd, P.J. Lam, T.W. Trull, R.R. Bidigare, J.K.B. Bishop, K.L. Casciotti, F. Dehairs, M. Elskens, M. Honda, D.M. Karl, D.A. Siegel, M.W. Silver, D.K. Steinberg, J. Valdes, B. Van Mooy and S. Wilson, 2007: Revisiting Carbon Flux through the Ocean’s Twilight Zone. Science, 316, 567-570. [pdf] [supplementary info]

Behrenfeld, M.J., and D.A. Siegel, 2007: Ocean productivity - Climate linkages imprinted in satellite observations. Global Change Newsletter, no. 68, Feb. 2007. [pdf]

Hood, R.R., E.A. Laws, M.J. Follows and D.A. Siegel, 2007: Modeling and prediction of marine microbial populations in the genomic era. Oceanography, 20, 155-165. [pdf]



Behrenfeld, M.J., R.T. O’Malley, D.A. Siegel, C.R. McClain, J.L. Sarmiento, G.C. Feldman, A.J. Milligan, P.G. Falkowski, R.M. Letelier & E. S. Boss, 2006: Climate-driven trends in contemporary ocean productivity. Nature, 444, 752-755.  [pdf] [supplementary info]

Westberry, T.K. and D.A. Siegel, 2006: Spatial and temporal distribution of Trichodesmium blooms in the world's oceans. Global Biogeochemical Cycles, 20, GB4016, doi:10.1029/2005GB002673 [pdf]

Toole, D.A., D. Slezak, R.P. Kiene, D.J. Kieber, and D.A. Siegel, 2006: Effects of solar radiation on dimethylsulfide cycling processes in the western Atlantic Ocean. Deep-Sea Research, Part I, 53, 136–153 [pdf]



Siegel, D.A., S. Maritorena, N.B. Nelson, M.J. Behrenfeld and C.R. McClain, 2005: Colored dissolved organic matter and its influence on the satellite-based characterization of the ocean biosphere. Geophysical Research Letters, 32, L20605, doi:10.1029/2005GL024310 [pdf]

Siegel, D.A., S. Maritorena, N.B. Nelson and M.J. Behrenfeld, 2005: Independence and interdependencies of global ocean color properties; Reassessing the bio-optical assumption. Journal of Geophysical Research, 110, C07011, doi:10.1029/2004JC002527. [pdf]

Behrenfeld, M.J., E. Boss, D.A. Siegel and D.M. Shea, 2005, Carbon-based ocean productivity and phytoplankton physiology from space. Global Biogeochemical Cycles, 19, DOI:10.1029/2004GB002299.[pdf]

Gaylord, B., S.D. Gaines, D.A. Siegel and M. Carr, 2005: Marine reserves can exploit life history and population structure to enable higher fisheries yields. Ecological Applications, 15, 2180–2191. [pdf]

Maritorena, S., and D.A. Siegel, 2005: Consistent merging of satellite ocean color data using a semi-analytical model, Remote Sensing of the Environment, 94, 429-440.[pdf]

Westberry T.K., D.A. Siegel and A. Submaranium, 2005: An improved bio-optical model for the remote sensing of Trichodesmium spp. blooms. Journal of Geophysical Research, 110, C06012, doi:10.1029/2004JC002517. [pdf]

Warrick J.A., L. Washburn, M.A. Brzezinski, and D.A. Siegel, 2005: Nutrient contributions to the Santa Barbara Channel, California, from the ephemeral Santa Clara River. Estuarine, Coastal and Shelf Research, 62, 559-574.



Toole, D.A., and D.A. Siegel, 2004: Light-driven cycling of dimethylsulfide (DMS) in the Sargasso Sea: closing the loop.  Geophysical Research Letters, 31, L09308, DOI: 10.1029/2004GL019581.[pdf]

Otero, M.P., and D.A. Siegel, 2004: Spatial and temporal characteristics of sediment plumes and phytoplankton blooms in the Santa Barbara Channel. Deep-Sea Research, II, 51, 1129-1149. [pdf]

Warrick J.A., L.A.K. Mertes, L. Washburn, and D.A. Siegel, 2004: Dispersal forcing of southern California river plumes, based on field and remote sensing observations. Geo-Marine Letters, 24, 46–52.[pdf]

Warrick, J.A., L.A.K. Mertes, D.A. Siegel and C. MacKenzie, 2004: Estimating suspended sediment concentrations in turbid coastal waters with SeaWiFS.  International Journal of Remote Sensing, 25, 1995-2002.[pdf]

Nelson, N.B., D.A. Siegel, and J.A. Yoder, 2004: The spring bloom in the northwestern Sargasso Sea: Spatial extent and relationship with winter mixing. Deep-Sea Research, Part II. [pdf]



Siegel, D.A., B.P. Kinlan, B. Gaylord and S.D. Gaines, 2003:  Lagrangian descriptions of marine larval dispersion.  Marine Ecology Progress Series, 260, 83-96. [pdf] [supplemental info]

Chomko, R.M., H.R. Gordon, S. Maritorena and D.A. Siegel, 2003: Simultaneous determination of oceanic and atmospheric parameters for ocean color imagery by spectral optimization: a validation. Remote Sensing of the Environment, 84, 208-220.[pdf]

Westberry T.K., and D.A. Siegel, 2003: Phytoplankton natural fluorescence in the Sargasso Sea: Prediction of primary production and eddy induced nutrient fluxes. Deep-Sea Research, Part I, 50, 417-434. [pdf]

Toole, D.A., D.J. Kieber, R.P. Kiene, D.A. Siegel and N.B. Nelson, 2003: Photolysis and the dimethylsulfide (DMS) summer paradox in the Sargasso Sea. Limnology and Oceanography, 48, 1088-1100. [pdf]



Siegel, D.A., Maritorena, S., Nelson, N.B., Hansell, D.A., Lorenzi-Kayser, M., 2002. Global distribution and dynamics of colored dissolved and detrital organic materials. Journal of Geophysical Research, 107, 3228, doi:10.1029/2001JC000965. [pdf]

Siegel, D.A., S.C. Doney and J.A. Yoder, 2002: The spring bloom of phytoplankton in the North Atlantic Ocean and Sverdrup's critical depth hypothesis. Science, 296, 730-733. [pdf

Maritorena, S., D.A. Siegel and A.R. Peterson, 2002: Optimization of a semianalytical ocean color model for global-scale applications. Applied Optics-LP, 41, 2705-2714. [pdf]

Behrenfeld, M.J., E. Marańon, D.A. Siegel and S.B. Hooker, 2002: Photoacclimation and nutrient-based model of light-saturated photosynthesis for quantifying oceanic primary production. Marine Ecology-Progress Series, 228, 103-117. [pdf]

Nelson, N.B., and D.A. Siegel, 2002: Chromophoric DOM in the Open Ocean. In: Biogeochemistry of Marine Dissolved Organic Matter, D.A. Hansell and C.A. Carlson, eds. p. 547-578, Academic Press, San Diego, CA [pdf]

Siegel, D.A., and R.A. Armstrong, 2002: Corrigendum to "Siegel, D.A, and W.G. Deuser, 1997: Trajectories of sinking particles in the Sargasso Sea: Modeling of statistical funnels above deep-ocean sediment traps.  Deep-Sea Research, I , 44, 1,519-1,541", Deep-Sea Research, Part I, 49, 1115-1116.[pdf]

Shipe, R.F., U. Passow, M.A. Brzezinski, D.A. Siegel and A.L. Alldredge, 2002: Effects of the 1997-98 El Nino on seasonal variations in suspended and sinking particles in the Santa Barbara Basin. Progress in Oceanography, 54, 105-127.[pdf]



Siegel, DA. 2001: Oceanography - The Rossby rototiller. Nature, 409, 576-577. [pdf]

Siegel, D.A., N.B. Nelson, M.C. O'Brien, T.K. Westberry and others, 2001: The Bermuda BioOptics Project: Bio-optical modeling of primary production from space-sensible variables. Deep Sea Research, II, 48, 1865-1896. [pdf]

Toole, D.A., and D.A. Siegel, 2001: Modes and mechanisms of ocean color variability in the Santa Barbara Channel. Journal of Geophysical Research, 106, 26,985-27,000. [pdf]

Sorensen, J.C., and D.A. Siegel, 2001: Variability and models of the effective quantum yield of carbon assimilation in the Sargasso Sea, Deep Sea Research, II, 48, 2005-2035.  [pdf]

Nelson, N.B., N.R. Bates, D.A. Siegel and A.F. Michaels, 2001: Spatial variability of the CO2 sink in the Sargasso Sea. Deep Sea Research, II, 48, 1801-1821. [pdf]

Dickey, T., S. Zedler, D. Frye, H. Jannasch, D. Manov, D. Sigurdson, J. D. McNeil, L. Dobeck, X. Yu, T. Gilboy, C. Bravo, S. C. Doney, D.A. Siegel and N. Nelson, 2001: Physical and biogeochemical variability from hours to years at the Bermuda Testbed Mooring: June 1994 - March 1998. Deep Sea Research, II, 48, 2105-2140. [pdf]



Toole, D.A., D.A. Siegel, D.W. Menzies, M.J. Neumann and R.C. Smith, 2000: Remote sensing reflectance determinations in coastal environments: impact of instrumental characteristics and environmental variability. Applied Optics, 39, 456-469.[pdf]

Siegel, D.A., M. Wang, S.Maritorena and W. Robinson, 2000: Atmospheric correction of satellite ocean color imagery: The black pixel assumption. Applied Optics, 39, 3582-2591.[pdf]

Ohlmann, J.C., D.A. Siegel, and C. Mobley, 2000: Ocean radiant heating: I., Optical influences. Journal of Physical Oceanography, 30, 1833-1848.[pdf]

Ohlmann, J.C., and D.A. Siegel, 2000: Ocean radiant heating: II., Parameterization and influence on sea surface temperature prediction. Journal of Physical Oceanography, 30, 1849-1865.[pdf]



Siegel, D.A., E. Fields and D.J. McGillicuddy, Jr., 1999: Mesoscale motions, satellite altimetry and new production in the Sargasso Sea.  Journal of Geophysical Research, 104, 13359-13379. [pdf]

Siegel, D.A., T. Westberry, and J.C. Ohlmann, 1999: On cloud color and ocean radiant heating. Journal of Climate, 12, 1101-1116.[pdf]

McGillicuddy Jr., D.J., R.J. Johnson, D.A. Siegel, A.F. Michaels, N. Bates and A.H. Knap, 1999: Mesoscale variability of ocean biogeochemistry in the Sargasso Sea. Journal of Geophysical Research, 104, 13381-13394. [pdf]



Siegel, D.A., 1998: Resource competition in a discrete environment: Why are plankton distributions paradoxical? Limnology and Oceanography, 43, 1133-1146.[pdf]

McGillicuddy Jr., D.J., A.R. Robinson, D.A. Siegel, H.W. Jannasch, R. Johnson, T.D. Dickey, J. McNeil, A.F. Michaels and A.H. Knap, 1998: Influence of mesoscale eddies on new production in the Sargasso Sea. Nature, 394, 263-265. [pdf]

Ohlmann, J.C., D.A. Siegel, and L. Washburn, 1998, Radiant heating of the western equatorial Pacific during TOGA-COARE. Journal of Geophysical Research, 103, 5379-5395. [pdf]

Nelson, N.B., D.A. Siegel, and A.F. Michaels, 1998: Seasonal dynamics of colored dissolved material in the Sargasso Sea.  Deep Sea Research, I, 45, 931-957. [pdf]

O'Reilly, J., S. Maritorena, B.G. Mitchell, D.A. Siegel, K.L. Carder, M. Kahru, S.A. Garver, C.R. McClain, 1998: Ocean color algorithms for SeaWiFS. Journal of Geophysical Research, 103, 24,937-24,953.  [pdf]



Siegel, D.A, and W.G. Deuser, 1997: Trajectories of sinking particles in the Sargasso Sea: Modeling of statistical funnels above deep-ocean sediment traps.  Deep-Sea Research, I , 44, 1,519-1,541. [pdf]

Garver, S.A., and D.A. Siegel, 1997: Inherent optical property inversion of ocean color spectra and its biogeochemical interpretation: I. Time series from the Sargasso Sea. Journal of Geophysical Research., 102, 18,607-18,625. [pdf]


Yet Older:

Siegel, D.A., and A.F. Michaels, 1996: Quantification of non-algal light attenuation in the Sargasso Sea: Implications for biogeochemistry and remote sensing.  Deep-Sea Research II, 43, 321-345. [pdf]

Ohlmann, J.C., D. A. Siegel, and C. Gautier, 1996: Ocean mixed layer radiant heating and solar penetration: A global analysis. Journal of Climate, 9, 2265-2280. [pdf]

Siegel, D.A., J.C. Ohlmann, L. Washburn, R.R. Bidigare, C. Nosse, E. Fields, and Y. Zhou, 1995: Solar radiation, phytoplankton pigments and the radiant heating of the Equatorial Pacific warm pool. Journal of Geophysical Research, 100, 4885-4891.  [pdf]

Siegel, D.A., A.F. Michaels, J. Sorensen, M.C. O'Brien, and M.A. Hammer, 1995: Seasonal variability of light availability and its utilization in the Sargasso Sea. Journal of Geophysical Research100, 8695-8713. [pdf]

Garver, S., D.A. Siegel, and B.G. Mitchell, 1994: A statistical analysis of particulate absorption spectra: What can a satellite ocean color imager see? Limnology and Oceanography, 39, 1349-1367. [pdf]

Siegel, D.A., and J.A. Domaradzki, 1994: Large-eddy simulation of the decay of stably-stratified oceanic turbulence. Journal of Physical Oceanography, 24, 2353-2386. [pdf]

Michaels, A.F, D.A. Siegel, R. Johnson, A.H. Knap and J.N. Galloway, 1993: Episodic inputs of atmospheric nitrogen to the Sargasso Sea: Contributions to new production and phytoplankton blooms. Global Biogeochemical Cycles, 7, 339-351.

Dickey, T.D., and D.A. Siegel, (eds.), 1993: Bio-optics in U.S. JGOFS.  Report of the Bio-Optics Workshop, U. S. GOFS Planning and Coordination Office, Woods Hole, MA, p 180.  

Siegel, D.A., T.C. Granata, A.F. Michaels and T.D. Dickey, 1990: Mesoscale eddy diffusion, particle sinking and the interpretation of sediment trap data. Journal of Geophysical Research, 95, 5305-5311.  

Siegel, D.A., R. Iturriaga, R.R. Bidigare, H. Pak, R.C. Smith, T.D. Dickey, J. Marra and K.S. Baker, 1990: Meridional variations of the springtime phytoplankton community in the Sargasso Sea. Journal of Marine Research, 48, 379-412.

Siegel, D.A., T.D. Dickey, L. Washburn, M.K. Hamilton and B.G. Mitchell, 1989: Optical determination of particulate abundance and production variations in the oligotrophic ocean. Deep-Sea Research, 36, 211-222. 

Iturriaga, R., and D.A. Siegel, 1989: Microphotometric characterization of phytoplankton and detrital absorption properties in the Sargasso Sea. Limnology and Oceanography, 34, 1706-1726.

Washburn, L., D.A. Siegel, T.D. Dickey and M.K. Hamilton, 1989: Isopycnal mixing and the distribution of particles across the North Pacific Subtropical Front. Deep-Sea Research, 36, 1607-1620. 

Siegel, D.A., B.H. Jones, T.D. Dickey, I. Haydock and A. Bratkovich, 1988: Effects of nearshore upwelling on coliform dispersion near the Whites Point Outfall. Ocean Processes in Marine Pollution, 5, 43-48. 

Siegel, D.A., and T.D. Dickey, 1987: Observations of the vertical structure of the diffuse attenuation coefficient spectrum. Deep-Sea Research., 34, 547-563.

Siegel, D.A., and T.D. Dickey, 1987: On the parameterization of irradiance for open ocean photoprocesses. Journal of Geophysical Research, 92, 14,648-14,662.


Curriculum Vita:


Awards and Honors

Academic Positions Held

National and International Service

Synergistic Activities:

Served on a science panel for siting marine protected areas around the Channel Islands, California. Lead the Flow, Fish and Fishing biocomplexity project which performs collaborative research with local fishermen groups.  Provided algorithms for use in the operational product stream for the SeaWiFS and MODIS missions and regularly assist project staff.  Conduct a field program (Plumes and Blooms) that gives ~10 undergraduate students the opportunity to go on a research cruise each year.