Abstract
Understanding of nitrogen cycling on continental shelves, a critical component of global nutrient cycling, is hampered by limited observations compared to the strong variability on a wide range of time and space scales. Numerical models have the potential to partially alleviate this issue by filling spatiotemporal data gaps and hence resolving annual area-integrated nutrient fluxes. In this study, a three-dimensional biogeochemical-circulation model was implemented to simulate the Mid-Atlantic Bight (MAB) nitrogen budget. Model results demonstrate that, on average, MAB net community production (NCP) was positive (+0.27 Tg N/year), indicating net autotrophy. Interannual variability in NCP was strong, with annual values ranging between 0.19 and 0.41 Tg N/year. Along-shelf and across-shelf horizontal transport fluxes were the other dominant terms in the nitrogen budget and were primarily responsible for this NCP variability. The along-shelf current transported nitrogen from the north (0.65 Tg N/year) into the MAB, supplementing the nitrogen entering from terrestrial inputs (0.27 Tg N/year). However, NCP was highest in the year when total water volume transport and inorganic nitrogen input was strongest across the continental slope in the southern MAB, rather than when terrestrial inputs were greatest. Interannual variability of NCP appears to be linked to changes in the positions of the Gulf Stream and Slope Water Gyre. Overall, the strong spatiotemporal variability of the nitrogen fluxes highlights the importance of observations throughout all seasons and multiple years in order to accurately resolve the current status and future changes of the MAB nitrogen budget.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 113-134 |
| Number of pages | 22 |
| Journal | Journal of Geophysical Research: Oceans |
| Volume | 124 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 2019 |
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All Science Journal Classification (ASJC) codes
- Geophysics
- Forestry
- Oceanography
- Aquatic Science
- Ecology
- Water Science and Technology
- Soil Science
- Geochemistry and Petrology
- Earth-Surface Processes
- Atmospheric Science
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science
- Palaeontology
Cite this
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Ocean Circulation Causes Strong Variability in the Mid-Atlantic Bight Nitrogen Budget. / Friedrichs, Marjorie A.M.; St-Laurent, Pierre; Xiao, Yongjin; Hofmann, Eileen; Hyde, Kimberly; Mannino, Antonio; Najjar, Raymond G.; Narváez, Diego A.; Signorini, Sergio R.; Tian, Hanqin; Wilkin, John; Yao, Yuanzhi; Xue, Jianhong.
In: Journal of Geophysical Research: Oceans, Vol. 124, No. 1, 01.2019, p. 113-134.Research output: Contribution to journal › Article
TY - JOUR
T1 - Ocean Circulation Causes Strong Variability in the Mid-Atlantic Bight Nitrogen Budget
AU - Friedrichs, Marjorie A.M.
AU - St-Laurent, Pierre
AU - Xiao, Yongjin
AU - Hofmann, Eileen
AU - Hyde, Kimberly
AU - Mannino, Antonio
AU - Najjar, Raymond G.
AU - Narváez, Diego A.
AU - Signorini, Sergio R.
AU - Tian, Hanqin
AU - Wilkin, John
AU - Yao, Yuanzhi
AU - Xue, Jianhong
PY - 2019/1
Y1 - 2019/1
N2 - Understanding of nitrogen cycling on continental shelves, a critical component of global nutrient cycling, is hampered by limited observations compared to the strong variability on a wide range of time and space scales. Numerical models have the potential to partially alleviate this issue by filling spatiotemporal data gaps and hence resolving annual area-integrated nutrient fluxes. In this study, a three-dimensional biogeochemical-circulation model was implemented to simulate the Mid-Atlantic Bight (MAB) nitrogen budget. Model results demonstrate that, on average, MAB net community production (NCP) was positive (+0.27 Tg N/year), indicating net autotrophy. Interannual variability in NCP was strong, with annual values ranging between 0.19 and 0.41 Tg N/year. Along-shelf and across-shelf horizontal transport fluxes were the other dominant terms in the nitrogen budget and were primarily responsible for this NCP variability. The along-shelf current transported nitrogen from the north (0.65 Tg N/year) into the MAB, supplementing the nitrogen entering from terrestrial inputs (0.27 Tg N/year). However, NCP was highest in the year when total water volume transport and inorganic nitrogen input was strongest across the continental slope in the southern MAB, rather than when terrestrial inputs were greatest. Interannual variability of NCP appears to be linked to changes in the positions of the Gulf Stream and Slope Water Gyre. Overall, the strong spatiotemporal variability of the nitrogen fluxes highlights the importance of observations throughout all seasons and multiple years in order to accurately resolve the current status and future changes of the MAB nitrogen budget.
AB - Understanding of nitrogen cycling on continental shelves, a critical component of global nutrient cycling, is hampered by limited observations compared to the strong variability on a wide range of time and space scales. Numerical models have the potential to partially alleviate this issue by filling spatiotemporal data gaps and hence resolving annual area-integrated nutrient fluxes. In this study, a three-dimensional biogeochemical-circulation model was implemented to simulate the Mid-Atlantic Bight (MAB) nitrogen budget. Model results demonstrate that, on average, MAB net community production (NCP) was positive (+0.27 Tg N/year), indicating net autotrophy. Interannual variability in NCP was strong, with annual values ranging between 0.19 and 0.41 Tg N/year. Along-shelf and across-shelf horizontal transport fluxes were the other dominant terms in the nitrogen budget and were primarily responsible for this NCP variability. The along-shelf current transported nitrogen from the north (0.65 Tg N/year) into the MAB, supplementing the nitrogen entering from terrestrial inputs (0.27 Tg N/year). However, NCP was highest in the year when total water volume transport and inorganic nitrogen input was strongest across the continental slope in the southern MAB, rather than when terrestrial inputs were greatest. Interannual variability of NCP appears to be linked to changes in the positions of the Gulf Stream and Slope Water Gyre. Overall, the strong spatiotemporal variability of the nitrogen fluxes highlights the importance of observations throughout all seasons and multiple years in order to accurately resolve the current status and future changes of the MAB nitrogen budget.
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U2 - 10.1029/2018JC014424
DO - 10.1029/2018JC014424
M3 - Article
AN - SCOPUS:85059585464
VL - 124
SP - 113
EP - 134
JO - Journal of Geophysical Research: Atmospheres
JF - Journal of Geophysical Research: Atmospheres
SN - 2169-897X
IS - 1
ER -