A high-resolution marine mercury model MITgcm-ECCO2-Hg with online biogeochemistry
Name
gmd-16-5915-2023.pdf
Description
Published version
Size
4.76 MB
Format
Adobe PDF
Checksum (MD5)
8dc9f16d0b3de98ef160af5811876eb5
Author(s)
Zhu, Siyu
Wu, Peipei
Zhang, Siyi
Jahn, Oliver
Li, Shu
Zhang, Yanxu
Date Issued
October 20, 2023
Journal
Geoscientific Model Development
Publisher
Copernicus GmbH
Citation
Zhu, S., Wu, P., Zhang, S., Jahn, O., Li, S., and Zhang, Y.: A high-resolution marine mercury model MITgcm-ECCO2-Hg with online biogeochemistry, Geosci. Model Dev., 16, 5915–5929.
Version
Final published version
Abstract
Mercury (Hg) is a global persistent contaminant. Modeling studies are useful means of synthesizing a current understanding of the Hg cycle. Previous studies mainly use coarse-resolution models, which makes it impossible to analyze the role of turbulence in the Hg cycle and inaccurately describes the transport of kinetic energy. Furthermore, all of them are coupled with offline biogeochemistry, and therefore they cannot respond to short-term variability in oceanic Hg concentration. In our approach, we utilize a high-resolution ocean model (MITgcm-ECCO2, referred to as “high-resolution-MITgcm”) coupled with the concurrent simulation of biogeochemistry processes from the Darwin Project (referred to as “online”). This integration enables us to comprehensively simulate the global biogeochemical cycle of Hg with a horizontal resolution of 1/5 ◦ . The finer portrayal of surface Hg concentrations in estuarine and coastal areas, strong western boundary flow and upwelling areas, and concentration diffusion as vortex shapes demonstrate the effects of turbulence that are neglected in previous models. Ecological events such as algal blooms can cause a sudden enhancement of phytoplankton biomass and chlorophyll concentrations, which can also result in a dramatic change in particle-bound Hg (HgP aq) sinking flux simultaneously in our simulation. In the global estuary region, including riverine Hg input in the high-resolution model allows us to reveal the outward spread of Hg in an eddy shape driven by finescale ocean currents. With faster current velocities and diffusion rates, our model captures the transport and mixing of Hg from river discharge in a more accurate and detailed way and improves our understanding of Hg cycle in the ocean.
MIT Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.5194/gmd-16-5915-2023
