A new model of the marine ecosystem coupled into a global Earth System Climate Model suitable for long-term (multimillennial timescale) simulations is presented. The model is based on nitrate as the sole limiting nutrient. Prognostic equations for nutrients, phytoplankton, zooplankton, and detritus are solved online in the three-dimensional ocean circulation...
If a scientist can predict the weather (poorly)
Why cannot he predict fish yields (yet more poorly)? – a clerihew by Chris Corkett.
Recent long term historical studies of commercial fisheries have pointed to a well established pattern of overfishing. Under the principle of transference – what is true in...
Paleoclimate records from glacial Indian and Pacific oceans sediments document millennial-scale fluctuations of subsurface dissolved oxygen levels and denitrification coherent with North Atlantic temperature oscillations. Yet the mechanism of this teleconnection between the remote ocean basins remains elusive. Here we present model simulations of the oxygen and nitrogen cycles that...
A coupled climate-carbon cycle model and ice core CO2 data from the last glacial
period are used to explore the impact of changes in ocean circulation on atmospheric
CO2 concentrations on millennial time scales. In the model, stronger wind
driven circulation increases atmospheric CO2. Changes in the buoyancy driven
deep...
Paleoclimate records from glacial Indian and Pacific oceans sediments document millennial-scale fluctuations of subsurface dissolved oxygen levels and denitrification coherent with North Atlantic temperature oscillations. Yet the mechanism of this teleconnection between the remote ocean basins remains elusive. Here we present model simulations of the oxygen and nitrogen cycles that...
The primary impacts of anthropogenic CO2 emissions on marine biogeochemical cycles predicted so far include ocean acidification, global warming induced shifts in biogeographical provinces, and a possible negative feedback on atmospheric CO2 levels by CO2-fertilized biological production. Here we report a new potentially significant impact on the oxygen-minimum zones of...
A new model of global climate, ocean circulation, ecosystems, and biogeochemical cycling, including a fully coupled carbon cycle, is presented and evaluated. The model is consistent with multiple observational data sets from the past 50 years as well as with the observed warming of global surface air and sea temperatures...
Earth's climate and the concentrations of the atmospheric greenhouse gases carbon dioxide (CO2) and nitrous oxide (N2O) varied strongly on millennial timescales during past glacial periods. Large and rapid warming events in Greenland and the North Atlantic were followed by more gradual cooling, and are highly correlated with fluctuations of...
We present a new nitrogen isotope model incorporated into the three-dimensional ocean component of a global Earth System Climate Model designed for millennial timescale simulations. The model includes prognostic tracers for the stable nitrogen isotopes, ¹⁴N and ¹⁵N, in the nitrate (NO₃ˉ), phytoplankton, zooplankton, and detritus variables of the marine...
What is the uncertainty of climate-carbon cycle projections in response to anthropogenic greenhouse gas emissions and how can we reduce this uncertainty? We address this question by quantifying the ability of available ocean tracer observations to constrain the values of diapycnal diffusivity in the pelagic ocean (Kv), a key uncertain...