New study: the wind-upwelling interplay in the South Atlantic Bight
Source: http://www.aoml.noaa.gov/alongshore-winds-drive-variability-of-key-biogeochemical-processes
Archived: 2026-04-23 17:23
New study: the wind-upwelling interplay in the South Atlantic Bight
"
Alexandra Ceurvorst
Published on: April 8, 2026
On
Posted on
April 8, 2026
April 8, 2026
by
Alexandra Ceurvorst
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Physical Oceanography
,
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Alongshore winds drive variability of key biogeochemical processes
There’s a unique interplay between surface winds, the Gulf Stream current, and the continental shelf in the South Atlantic Bight (SAB), that has long been overlooked. Researchers have often speculated that the strength of the Gulf Stream and proximity to the coast impacts primary production and other processes driving essential ecosystems. However, to what degree has remained unclear.
A
new study
led by Fabian Gomez at the the Northern Gulf Institute (NGI), in collaboration with scientists at NOAA’s Atlantic Oceanographic and Meteorological Laboratory (AOML) and the Geophysical Fluid Dynamics Laboratory (GFDL), ties changes in the surface Gulf Stream speed to interannual changes in shelf-break upwelling and primary production across the SAB — variability largely driven by surface winds.
South Atlantic Bight bathymetry. The cross-shore sections A, B, C, and D used to examine vertical patterns are displayed in red.
The SAB is the stretch of coastal ocean between Cape Hatteras and the upper Florida Keys, and much of its physical and chemical properties are shaped by one of the strongest currents in the world – the Gulf Stream. When viewed from space across many years, the SAB intermittently flashes with ribbons of green, signaling bursts of phytoplankton growth and
elevated primary production.
Phytoplankton are microscopic, plant-like organisms that form the base of marine food webs. Like plants on land, they rely on sunlight and nutrients to grow. Infusions of nutrients to surface waters acts like fertilizer and fuels growth, which tends to occur when deeper, cold water is forced upwards in a process known as upwelling.
Using multi-decadal, high-resolution models of ocean currents and seawater biogeochemistry integrated with satellite measurements of chlorophyll, Gomez and his team found that the SAB’s shelf-break upwelling and phytoplankton production are strongly tied to the speed of the Gulf Stream near the shelf-break. The team deduced that this relationship is likely driven by bottom Ekman transport, a physical process in which interactions between the Gulf Stream and the seafloor move nutrient-rich waters onto the continental shelf.
Beyond that, the study shows that interannual changes in the surface Gulf Stream speed across the shelf-break are largely driven by local alongshore winds. While scientists have hypothesized surface winds may influence the Gulf Stream, this study represents the first in establishing a clear connection.
To support their model findings, the scientists used an “eye-in-the-sky” approach: satellite observations of chlorophyll, which is the pigment that makes phytoplankton green. Analyzing the intermittent flashes of greener waters (more phytoplankton), the study shows that the blooms were strongly correlated with interannual shifts in the surface winds and the Gulf Stream velocity.
Vertical patterns of alongshore velocity, temperature, nitrate, and chlorophyll anomalies during high productivity (a-d) years in a SAB cross-shore section. Dots represent significant anomalies. The long-term averages (climatologies) for these four variables are depicted in panels (e-h).
These upwelling anomalies influence more than just surface algal blooms—they impact the entirety of the SAB’s carbonate chemistry. More specifically, enhanced upwelling promotes a decline in seawater pH and aragonite saturation state which can increase acidic conditions that are potentially stressful for marine life.
Through this study, the team reveals a dynamic interplay among local winds, shelf-break upwelling, and Gulf Stream, deepening our understanding of the processes that regulate coastal productivity in the South Atlantic Bight. In doing so, it establishes a robust foundation of high-quality data and scientific insight of complex biogeochemical processes that are crucial to support ecosystem-based management decisions
given the central role of phytoplankton in sustaining marine food webs
, fisheries, and driving carbon cycling.
Tags
model
modeling
ocean observations
Physical Oceanography
satellite
Previous
Previous post:
From sample to source: tracking pollution pathways in AOML’s Molecular and Environmental Microbiology Lab
"
Alexandra Ceurvorst
Published on: April 8, 2026
On
Posted on
April 8, 2026
April 8, 2026
by
Alexandra Ceurvorst
to
Physical Oceanography
,
Publication Stories
Alongshore winds drive variability of key biogeochemical processes
There’s a unique interplay between surface winds, the Gulf Stream current, and the continental shelf in the South Atlantic Bight (SAB), that has long been overlooked. Researchers have often speculated that the strength of the Gulf Stream and proximity to the coast impacts primary production and other processes driving essential ecosystems. However, to what degree has remained unclear.
A
new study
led by Fabian Gomez at the the Northern Gulf Institute (NGI), in collaboration with scientists at NOAA’s Atlantic Oceanographic and Meteorological Laboratory (AOML) and the Geophysical Fluid Dynamics Laboratory (GFDL), ties changes in the surface Gulf Stream speed to interannual changes in shelf-break upwelling and primary production across the SAB — variability largely driven by surface winds.
South Atlantic Bight bathymetry. The cross-shore sections A, B, C, and D used to examine vertical patterns are displayed in red.
The SAB is the stretch of coastal ocean between Cape Hatteras and the upper Florida Keys, and much of its physical and chemical properties are shaped by one of the strongest currents in the world – the Gulf Stream. When viewed from space across many years, the SAB intermittently flashes with ribbons of green, signaling bursts of phytoplankton growth and
elevated primary production.
Phytoplankton are microscopic, plant-like organisms that form the base of marine food webs. Like plants on land, they rely on sunlight and nutrients to grow. Infusions of nutrients to surface waters acts like fertilizer and fuels growth, which tends to occur when deeper, cold water is forced upwards in a process known as upwelling.
Using multi-decadal, high-resolution models of ocean currents and seawater biogeochemistry integrated with satellite measurements of chlorophyll, Gomez and his team found that the SAB’s shelf-break upwelling and phytoplankton production are strongly tied to the speed of the Gulf Stream near the shelf-break. The team deduced that this relationship is likely driven by bottom Ekman transport, a physical process in which interactions between the Gulf Stream and the seafloor move nutrient-rich waters onto the continental shelf.
Beyond that, the study shows that interannual changes in the surface Gulf Stream speed across the shelf-break are largely driven by local alongshore winds. While scientists have hypothesized surface winds may influence the Gulf Stream, this study represents the first in establishing a clear connection.
To support their model findings, the scientists used an “eye-in-the-sky” approach: satellite observations of chlorophyll, which is the pigment that makes phytoplankton green. Analyzing the intermittent flashes of greener waters (more phytoplankton), the study shows that the blooms were strongly correlated with interannual shifts in the surface winds and the Gulf Stream velocity.
Vertical patterns of alongshore velocity, temperature, nitrate, and chlorophyll anomalies during high productivity (a-d) years in a SAB cross-shore section. Dots represent significant anomalies. The long-term averages (climatologies) for these four variables are depicted in panels (e-h).
These upwelling anomalies influence more than just surface algal blooms—they impact the entirety of the SAB’s carbonate chemistry. More specifically, enhanced upwelling promotes a decline in seawater pH and aragonite saturation state which can increase acidic conditions that are potentially stressful for marine life.
Through this study, the team reveals a dynamic interplay among local winds, shelf-break upwelling, and Gulf Stream, deepening our understanding of the processes that regulate coastal productivity in the South Atlantic Bight. In doing so, it establishes a robust foundation of high-quality data and scientific insight of complex biogeochemical processes that are crucial to support ecosystem-based management decisions
given the central role of phytoplankton in sustaining marine food webs
, fisheries, and driving carbon cycling.
Tags
model
modeling
ocean observations
Physical Oceanography
satellite
Previous
Previous post:
From sample to source: tracking pollution pathways in AOML’s Molecular and Environmental Microbiology Lab