We present a new mechanistic model, Stochastic Lagrangian Aggregate Model of Sinking particles (SLAMS) for the biological pump in the ocean, which tracks the evolution of individual particles as they aggregate, disaggregate, sink, and are altered by chemical and biological processes. SLAMS considers the impacts of ballasting by mineral phases, binding of aggregates by transparent exopolymer particles (TEP), zooplankton grazing, and the fractal geometry (porosity) of the aggregates. Parameterizations for age-dependent organic carbon (orgC) degradation kinetics, and disaggregation driven by zooplankton grazing and TEP degradation, are motivated by observed particle fluxes and size spectra throughout the water column. The model is able to explain observed variations in orgC export efficiency and rain ratio from the euphotic zone and to the sea floor as driven by sea surface temperature and the primary production rate and seasonality of primary production. The model provides a new mechanistic framework with which to predict future changes on the flux attenuation of orgC in response to climate change forcing.
Areas of Focus: Climate Change, Climate Science, Environment
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Climate Change
Climate change is an urgent global challenge. EPIC research is helping to assess its impacts, quantify its costs, and identify an efficient set of policies to reduce emissions and adapt...
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Climate Science
EPIC’s interdisciplinary team of researchers is contributing to a cross-cutting body of knowledge on the scientific causes of climate change and its social consequences.
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Environment
Producing and using energy damages people’s health and the environment. EPIC research is quantifying the social costs of energy choices and uncovering policies that help protect health while facilitating growth.