Publication Date:
2022-05-26
Description:
Author Posting. © American Geophysical Union, 2010. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 33(2), (2019): 181-199. doi:10.1029/2018GB005983.
Description:
One pathway of the biological pump that remains largely unquantified in many export models is the active transport of carbon from the surface ocean to the mesopelagic by zooplankton diel vertical migration (DVM). Here, we develop a simple representation of zooplankton DVM and implement it in a global export model as a thought experiment to illustrate the effects of DVM on carbon export and mesopelagic biogeochemistry. The model is driven by diagnostic satellite measurements of net primary production, algal biomass, and phytoplankton size structure. Due to constraints on available satellite data, the results are restricted to the latitude range from 60°N to 60°S. The modeled global export flux from the base of the euphotic zone was 6.5 PgC/year, which represents a 14% increase over the export flux in model runs without DVM. The mean (± standard deviation, SD) proportional contribution of the DVM‐mediated export flux to total carbon export, averaged over the global domain and the climatological seasonal cycle, was 0.16 ± 0.04 and the proportional contribution of DVM activity to total respiration within the twilight zone was 0.16 ± 0.06. Adding DVM activity to the model also resulted in a deep local maximum in the oxygen utilization profile. The model results were most sensitive to the assumptions for the fraction of individuals participating in DVM, the fraction of fecal pellets produced in the euphotic zone, and the fraction of grazed carbon that is metabolized.
Description:
Support for this work came from the National Science Foundation (OCE‐1434000 and OCE‐1657803) and the National Aeronautics and Space Administration (NASA) as part of the EXport Processes in the global Ocean from RemoTe Sensing (EXPORTS) field campaign (grant 80NSSC17K0692) and the North Atlantic Aerosol and Marine Ecosystems Study (NAAMES, grants NNX15AE72G and 80NSSC18K0018). The satellite data used as drivers for the model are available as supporting information. The World Ocean Atlas data (World Ocean Atlas 2009, Annual Climatology, 1 degree, Temperature, Salinity, Oxygen) containing temperature and oxygen measurements can be downloaded from the ERDAPP data server (https://coastwatch.pfeg.noaa.gov/erddap/index.html).
Description:
2019-07-19
Repository Name:
Woods Hole Open Access Server
Type:
Article
