low-frequency forcing (e.g., Monismith et al., 2002;
MacCready and Geyer, 2010), (3) the period(s) of variability captured by measurements or models (e.g., Blumberg
et al., 1999; Wang et al., 1999), or (4) the temporal lens
through which processes are examined (e.g., Stacey et al.,
2001; Chapin III et al., 2006).
Summary
Described very generally, a “time scale” is the time taken
by a process or sequence of events (OUP, 2013). However,
there exist many shades of meaning and usage of this term,
which is ubiquitous in engineering and increasingly so in
environmental science. Typically, a “time scale” implies
a time estimate, not a precise value. Comparison of time
scales for two or more coincident processes (be they physical, biological, or chemical) provides a diagnostic tool for
assessing the processes’ relative importance and, potentially, for simplifying complex equations.
Bibliography
Blumberg, A. F., Khan, L. A., and St. John, J. P., 1999. Threedimensional hydrodynamic model of New York Harbor region.
Journal of Hydraulic Engineering, 125, 799–816.
Buzzelli, C., Parker, M., Geiger, S., Wan, Y., Doering, P., and
Haunert, D., 2013. Predicting system-scale impacts of oyster
clearance on phytoplankton productivity in a small subtropical
estuary. Environmental Modeling and Assessment, 18, 185–198.
Chapin, F. S., III, Woodwell, G. M., Randerson, J. T., Rastetter,
E. B., Lovett, G. M., Baldocchi, D. D., Clark, D. A., Harmon,
M. E., Schimel, D. S., Valentini, R., Wirth, C., Aber, J. D., Cole,
J. J., Goulden, M. L., Harden, J. W., Heimann, M., Howarth,
R. W., Matson, P. A., McGuire, A. D., Melillo, J. M., Mooney,
H. A., Neff, J. C., Houghton, R. A., Pace, M. L., Ryan, M. G.,
Running, S. W., Sala, O. E., Schlesinger, W. H., and Schulze,
E. D., 2006. Reconciling carbon-cycle concepts, terminology,
and methods. Ecosystems, 9, 1041–1050.
Cloern, J. E., 1996. Phytoplankton bloom dynamics in coastal ecosystems: a review with some general lessons from sustained
investigation of San Francisco Bay, California. Reviews of Geophysics, 34(2), 127–168.
Cushman-Roisin, B., and Beckers, J.-M., 2011. Introduction to
Geophysical Fluid Dynamics: Physical and Numerical Aspects.
Waltham: Academic.
Dame, R. F., 2012. Ecology of Marine Bivalves: An Ecosystem
Approach, 2nd edn. Boca Raton: CRC Press.
de Brauwere, A., and Deleersnijder, E., 2010. Assessing the
parameterisation of the settling flux in a depth-integrated model
of the fate of decaying and sinking particles, with application to
fecal bacteria in the Scheldt Estuary. Environmental Fluid
Mechanics, 10, 157–175.
Fischer, H. B., List, E. J., Koh, R. C. Y., Imberger, J., and Brooks,
N. H., 1979. Mixing in Inland and Coastal Waters. San Diego:
Academic.
Jay, D. A., Geyer, W. R., and Montgomery, D. R., 2000. An ecological perspective on estuarine classification. In Hobbie, J. E. (ed.),
Estuarine Science: A Synthetic Approach to Research and Practice. Washington: Island Press, pp. 149–176.
Koseff, J. R., Holen, J. K., Monismith, S. G., and Cloern, J. E.,
1993. Coupled effects of vertical mixing and benthic grazing
on phytoplankton populations in shallow, turbid estuaries. Journal of Marine Research, 51, 843–868.
Litaker, W., Duke, C. S., Kenney, B. E., and Ramus, J., 1993. Shortterm environmental variability and phytoplankton abundance in
a shallow tidal estuary. II. Spring and fall. Marine Ecology Progress Series, 94, 141–154.
Lucas, L. V., 2010. Implications of estuarine transport for water
quality. In Valle-Levinson, A. (ed.), Contemporary Issues in
Estuarine Physics. Cambridge: Cambridge University Press,
pp. 272–306.
Lucas, L. V., Thompson, J. K., and Brown, L. R., 2009. Why are
diverse relationships observed between phytoplankton biomass
and transport time? Limnology and Oceanography, 54(1),
381–390.
MacCready, P., and Banas, N. S., 2011. Residual circulation,
mixing, and dispersion. In Wolanski, E., and McLusky, D. S.
(eds.), Treatise on Estuarine and Coastal Science. Waltham:
Academic, Vol. 2, pp. 75–89.
MacCready, P., and Geyer, W. R., 2010. Advances in estuarine
physics. Annual Review of Marine Science, 2, 35–58.
Middleburg, J. J., and Nieuwenhuize, J., 2000. Uptake of dissolved
inorganic nitrogen in turbid, tidal estuaries. Marine Ecology Progress Series, 192, 79–88.
Monismith, S. G., Kimmerer, W., Burau, J. R., and Stacey, M. T.,
2002. Structure and flow-induced variability of the subtidal
salinity field in Northern San Francisco Bay. Journal of Physical
Oceanography, 32, 3003–3019.
OUP, 2013. Oxford Dictionaries. Oxford: Oxford University Press.
http://oxforddictionaries.com.
Sheldon, J. E., and Alber, M., 2006. The calculation of estuarine
turnover times using freshwater fraction and tidal prism models:
a critical evaluation. Estuaries and Coasts, 29(1), 133–146.
Stacey, M. T., Burau, J. R., and Monismith, S. G., 2001. Creation of
residual flows in a partially stratified estuary. Journal of Geophysical Research, 106(C8), 17013–17037.
Wang, L., Sarnthein, M., Erlenkeuser, H., Grimalt, J., Grootes, P.,
Heilig, S., Ivanova, E., Kienast, M., Pelejero, C., and Pflaumann,
U., 1999. East Asian monsoon climate during the Late Pleistocene: high-resolution sediment records from the South China
Sea. Marine Geology, 156, 245–284.
Cross-references
Residence Time
TOMBOLO
Michel Michaelovitch de Mahiques
Oceanographic Institute of the University of São Paulo,
Sao Paulo, Brazil
Synonyms
Ayr (Northern Europe); Tie bar
Definition
A tombolo is a sediment deposit at the coast formed by
wave refraction and diffraction at the edges of an obstacle
(natural or artificial) originally detached from the
mainland.
Description
The formation of a tombolo is caused by the diffraction of
the wave at the ends of an obstacle, creating a convergence
of opposing flows of sediment transport. Depending on
TOMBOLO
713
MacCready and Geyer, 2010), (3) the period(s) of variability captured by measurements or models (e.g., Blumberg
et al., 1999; Wang et al., 1999), or (4) the temporal lens
through which processes are examined (e.g., Stacey et al.,
2001; Chapin III et al., 2006).
Summary
Described very generally, a “time scale” is the time taken
by a process or sequence of events (OUP, 2013). However,
there exist many shades of meaning and usage of this term,
which is ubiquitous in engineering and increasingly so in
environmental science. Typically, a “time scale” implies
a time estimate, not a precise value. Comparison of time
scales for two or more coincident processes (be they physical, biological, or chemical) provides a diagnostic tool for
assessing the processes’ relative importance and, potentially, for simplifying complex equations.
Bibliography
Blumberg, A. F., Khan, L. A., and St. John, J. P., 1999. Threedimensional hydrodynamic model of New York Harbor region.
Journal of Hydraulic Engineering, 125, 799–816.
Buzzelli, C., Parker, M., Geiger, S., Wan, Y., Doering, P., and
Haunert, D., 2013. Predicting system-scale impacts of oyster
clearance on phytoplankton productivity in a small subtropical
estuary. Environmental Modeling and Assessment, 18, 185–198.
Chapin, F. S., III, Woodwell, G. M., Randerson, J. T., Rastetter,
E. B., Lovett, G. M., Baldocchi, D. D., Clark, D. A., Harmon,
M. E., Schimel, D. S., Valentini, R., Wirth, C., Aber, J. D., Cole,
J. J., Goulden, M. L., Harden, J. W., Heimann, M., Howarth,
R. W., Matson, P. A., McGuire, A. D., Melillo, J. M., Mooney,
H. A., Neff, J. C., Houghton, R. A., Pace, M. L., Ryan, M. G.,
Running, S. W., Sala, O. E., Schlesinger, W. H., and Schulze,
E. D., 2006. Reconciling carbon-cycle concepts, terminology,
and methods. Ecosystems, 9, 1041–1050.
Cloern, J. E., 1996. Phytoplankton bloom dynamics in coastal ecosystems: a review with some general lessons from sustained
investigation of San Francisco Bay, California. Reviews of Geophysics, 34(2), 127–168.
Cushman-Roisin, B., and Beckers, J.-M., 2011. Introduction to
Geophysical Fluid Dynamics: Physical and Numerical Aspects.
Waltham: Academic.
Dame, R. F., 2012. Ecology of Marine Bivalves: An Ecosystem
Approach, 2nd edn. Boca Raton: CRC Press.
de Brauwere, A., and Deleersnijder, E., 2010. Assessing the
parameterisation of the settling flux in a depth-integrated model
of the fate of decaying and sinking particles, with application to
fecal bacteria in the Scheldt Estuary. Environmental Fluid
Mechanics, 10, 157–175.
Fischer, H. B., List, E. J., Koh, R. C. Y., Imberger, J., and Brooks,
N. H., 1979. Mixing in Inland and Coastal Waters. San Diego:
Academic.
Jay, D. A., Geyer, W. R., and Montgomery, D. R., 2000. An ecological perspective on estuarine classification. In Hobbie, J. E. (ed.),
Estuarine Science: A Synthetic Approach to Research and Practice. Washington: Island Press, pp. 149–176.
Koseff, J. R., Holen, J. K., Monismith, S. G., and Cloern, J. E.,
1993. Coupled effects of vertical mixing and benthic grazing
on phytoplankton populations in shallow, turbid estuaries. Journal of Marine Research, 51, 843–868.
Litaker, W., Duke, C. S., Kenney, B. E., and Ramus, J., 1993. Shortterm environmental variability and phytoplankton abundance in
a shallow tidal estuary. II. Spring and fall. Marine Ecology Progress Series, 94, 141–154.
Lucas, L. V., 2010. Implications of estuarine transport for water
quality. In Valle-Levinson, A. (ed.), Contemporary Issues in
Estuarine Physics. Cambridge: Cambridge University Press,
pp. 272–306.
Lucas, L. V., Thompson, J. K., and Brown, L. R., 2009. Why are
diverse relationships observed between phytoplankton biomass
and transport time? Limnology and Oceanography, 54(1),
381–390.
MacCready, P., and Banas, N. S., 2011. Residual circulation,
mixing, and dispersion. In Wolanski, E., and McLusky, D. S.
(eds.), Treatise on Estuarine and Coastal Science. Waltham:
Academic, Vol. 2, pp. 75–89.
MacCready, P., and Geyer, W. R., 2010. Advances in estuarine
physics. Annual Review of Marine Science, 2, 35–58.
Middleburg, J. J., and Nieuwenhuize, J., 2000. Uptake of dissolved
inorganic nitrogen in turbid, tidal estuaries. Marine Ecology Progress Series, 192, 79–88.
Monismith, S. G., Kimmerer, W., Burau, J. R., and Stacey, M. T.,
2002. Structure and flow-induced variability of the subtidal
salinity field in Northern San Francisco Bay. Journal of Physical
Oceanography, 32, 3003–3019.
OUP, 2013. Oxford Dictionaries. Oxford: Oxford University Press.
http://oxforddictionaries.com.
Sheldon, J. E., and Alber, M., 2006. The calculation of estuarine
turnover times using freshwater fraction and tidal prism models:
a critical evaluation. Estuaries and Coasts, 29(1), 133–146.
Stacey, M. T., Burau, J. R., and Monismith, S. G., 2001. Creation of
residual flows in a partially stratified estuary. Journal of Geophysical Research, 106(C8), 17013–17037.
Wang, L., Sarnthein, M., Erlenkeuser, H., Grimalt, J., Grootes, P.,
Heilig, S., Ivanova, E., Kienast, M., Pelejero, C., and Pflaumann,
U., 1999. East Asian monsoon climate during the Late Pleistocene: high-resolution sediment records from the South China
Sea. Marine Geology, 156, 245–284.
Cross-references
Residence Time
TOMBOLO
Michel Michaelovitch de Mahiques
Oceanographic Institute of the University of São Paulo,
Sao Paulo, Brazil
Synonyms
Ayr (Northern Europe); Tie bar
Definition
A tombolo is a sediment deposit at the coast formed by
wave refraction and diffraction at the edges of an obstacle
(natural or artificial) originally detached from the
mainland.
Description
The formation of a tombolo is caused by the diffraction of
the wave at the ends of an obstacle, creating a convergence
of opposing flows of sediment transport. Depending on
TOMBOLO
713