Empirical algorithms are developed using high-quality GO-SHIP hydrographic measurements of commonly measured parameters (temperature, salinity, pressure, nitrate, and oxygen) that estimate pH in the Pacific sector of the Southern Ocean. The coefficients of determination, R² , are 0.98 for pH from nitrate (pH^N) and 0.97 for pH from oxygen (pH^Ox)...
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. Sarmiento, and
R. Wanninkhof (2016), Empirical algorithms
to estimate water column pH in the
Southern Ocean
Empirical algorithms are developed using high-quality GO-SHIP hydrographic measurements of commonly measured parameters (temperature, salinity, pressure, nitrate, and oxygen) that estimate pH in the Pacific sector of the Southern Ocean. The coefficients of determination, R² , are 0.98 for pH from nitrate (pH^N) and 0.97 for pH from oxygen (pH^Ox)...
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in the Southern Ocean
N. L. Williams1*, L. W. Juranek1, K. S. Johnson2, R. A. Feely3, S. C. Riser4
Empirical algorithms are developed using high-quality GO-SHIP hydrographic measurements of commonly measured parameters (temperature, salinity, pressure, nitrate, and oxygen) that estimate pH in the Pacific sector of the Southern Ocean. The coefficients of determination, R² , are 0.98 for pH from nitrate (pH^N) and 0.97 for pH from oxygen (pH^Ox)...
Space-based observations offer unique capabilities for studying spatial and temporal dynamics of the upper ocean inorganic carbon cycle and, in turn, supporting research tied to ocean acidification (OA). Satellite sensors measuring sea surface temperature, color, salinity, wind, waves, currents, and sea level enable a fuller understanding of a range of...
The Surface Ocean CO2 Atlas (SOCAT), an activity of the international marine carbon research community, provides access to synthesis and gridded fCO2 (fugacity of carbon dioxide) products for the surface oceans. Version 2 of SOCAT is an update of the previous release (version 1) with more data (increased from 6.3...
A novel, low-cost instrument capable of measuring surface water PCO₂ was designed for use in dynamic, shallow-water environments. The instrument was tested in the Yaquina River Estuary, a macrotidal estuary known to experience a wide range of conditions ranging from dominance by the coastal ocean during summer upwelling to substantial...
Physical-biological interactions in the Southern Ocean were investigated using remote sensing data from several different satellite sensors. Satellite sea surface temperature data were used to study the dynamics of the Antarctic Polar Front (PF). Satellite ocean color data were used to estimate surface chlorophyll concentrations and their relation to various...
Continental shelf sediments are sinks for dissolved oxygen and sources of many major and minor nutrients required for oceanic surface primary production, resulting in a strong coupling between benthic and pelagic biogeochemical cycling. However, the influence and spatiotemporal variability of benthic remineralization on bottom-water chemistry and the supply of nutrients...
The variability of coastal carbonate chemistry continues to provide significant hurdles for understanding interactions between anthropogenic and natural CO2 cycling and resultant effects on coastal acidification dynamics. Attribution of the anthropogenic component is vital for identifying the impacts of increasing atmospheric carbon on coastal habitats such as coral reefs, upwelling...
Shallow coastal waters serve an important role as long-term carbon (C) sinks because they capture terrestrial C
and retain internally produced C in wetlands and sediments. We show that tropical cyclones (TCs) can lead to
rapid CO₂ efflux from estuaries, driven by physical and biogeochemical perturbation of these coastal C...
From June 2009 to July 2010, we conducted 27 continuous-flow surveys of surface water CO₂ partial pressure (pCO₂) along the longitudinal axis of the Neuse River Estuary (NRE), North Carolina ranging from the tidal freshwater region to the polyhaline border with the Pamlico Sound. Lateral transects were also conducted at...
The Bering Sea and Gulf of Alaska support a number of commercially important flatfish fisheries. These high latitude ecosystems are predicted to be most immediately impacted by ongoing ocean acidification, but the range of responses by commercial fishery species has yet to be fully explored. In this study, we examined...
Headwater streams comprise nearly 90% of the total length of perennial channels in global catchments. They mineralize organic carbon entering from terrestrial systems, evade terrestrial carbon dioxide (CO₂ ), and generate and remove carbon through in-stream primary production and respiration. Despite their importance, headwater streams are often neglected in global...
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]2.0.CO%3B2. 290
MacIntyre, S., R. Wanninkhof, and J. Chanton (1995), Trace gas exchange across the
We assess the global balance of calcite export through the water column and burial in sediments as it varies regionally. We first drive a comprehensive 1-D model for sediment calcite preservation with globally gridded field observations and satellite-based syntheses. We then reformulate this model into a simpler five-parameter box model,...
Analysis of satellite ocean color, sea surface temperature, and sea ice cover data reveals consistent patterns between biological production, iron availability, and physical forcings in the Southern Ocean. The consistency of these patterns, in conjunction with information on physical conditions during the last glacial maximum (LGM), enables estimates of export...
Observations from Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) biogeochemical profiling Argo floats are used to characterize the climatological seasonal cycles and drivers of dissolved inorganic carbon, total alkalinity, pH, the partial pressure of carbon dioxide (CO2), and the saturation state of aragonite at the surface and at...
Many ocean regions important to the global carbon budget, including the equatorial Pacific Ocean, have low chlorophyll concentrations despite high levels of conventional nutrients. Iron may instead by the limiting nutrient, and elevated input of terrigenous Fe during windy glacial episodes has been hypothesized to stimulate oceanic productivity through time...
A globally integrated carbon observation and analysis
system is needed to improve the fundamental understanding
of the global carbon cycle, to improve our ability to
project future changes, and to verify the effectiveness of policies
aiming to reduce greenhouse gas emissions and increase
carbon sequestration. Building an integrated carbon observation...
We determine rates of gross photosynthetic O₂ production (GOP) and net community O₂ production (NCP) using the triple oxygen isotope and O₂/Ar approach on two spring and two late summer meridional transects of the NE Pacific. Observed GOP and NCP in the subtropical (89 ± 9 and 8.3 ± 1.3...
Analysis of observations and sensitivity experiments with a new three-dimensional global model of stable carbon isotope cycling elucidate processes that control the distribution of delta C-13 of dissolved inorganic carbon (DIC) in the contemporary and preindustrial ocean. Biological fractionation and the sinking of isotopically light delta C-13 organic matter from...
Chemical and biological sensor technologies have advanced rapidly in the past five years. Sensors that require low power and operate for multiple years are now available for oxygen, nitrate, and a variety of bio-optional properties that serve as proxies for important components of the carbon cycle (e.g., particulate organic carbon)....
The subarctic-subtropical transition zone in the North Pacific represents the second largest sink of
atmospheric carbon dioxide in the world ocean, yet the relative importance of physical and biological processes in
this uptake is debated. In a step toward understanding the spatiotemporal variability of environmental,
physiological, and ecological factors that...
Continental margin carbon cycling is complex, highly variable over a range of space and time scales, and forced by multiple physical and biogeochemical drivers. Predictions of globally significant air–sea CO₂ fluxes in these regions have been extrapolated based on very sparse data sets. We present here a method for predicting...
Time-series observations are critical to understand the structure, function, and dynamics of marine ecosystems. The Hawaii Ocean Time-series program has maintained near-monthly sampling at Station ALOHA (22°45′N, 158°00′W) in the oligotrophic North Pacific Subtropical Gyre (NPSG) since 1988 and has identified ecosystem variability over seasonal to interannual timescales. To further...
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I, 54(6), 951–974, doi:910.1016/j.dsr.2007.1002.1007.
6
Wanninkhof, R. (2014
Satellite measurements allow global assessments of phytoplankton concentrations and, from observed temporal changes in biomass, direct access to net biomass accumulation rates (r). For the subarctic Atlantic basin, analysis of annual cycles in r reveals that initiation of the annual blooming phase does not occur in spring after stratification surpasses...
We use autonomous gas measurements to examine the metabolic balance (photosynthesis
minus respiration) of coastal Antarctic waters during the spring/summer growth season. Our observations
capture the development of a massive phytoplankton bloom and reveal striking variability in pCO₂ and
biological oxygen saturation (ΔO₂/Ar) resulting from large shifts in community metabolism...
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):1307-1312.
3
2. WanninkhofR (1992) Relationship between wind-speed and gas exchange over the
Optical variability occurs in the near-surface and upper ocean on very short time and space scales (e.g., milliseconds and millimeters and less) as well as greater scales. This variability is caused by solar, meteorological, and other physical forcing as well as biological and chemical processes that affect optical properties and...
Understanding and modeling microbial responses and feedbacks to climate change is hampered by a lack of a framework in the pelagic environment by which to link local mechanism to large scale patterns. Where terrestrial ecology draws from landscape theory and practice to address issues of scale, the pelagic seascape concept...
Various human activities, including fossil fuel combustion and forest clearing, emit about eight petagrams (or billion tons) of carbon in the form of CO2 into the atmosphere annually. The global ocean absorbs about two petagrams of CO2, and about a half of that amount is absorbed by the Southern Ocean...
The Southern Ocean plays an important role in the ocean’s uptake of heat and carbon yet the processes controlling this uptake are not well understood. To date, more than 100 biogeochemical profiling floats that measure water column pH, oxygen, nitrate, fluorescence, and backscattering at 10-day intervals have been deployed throughout...
During the Southern Ocean Iron Experiment (SOFeX), January-February 2002, two iron fertilization experiments were conducted at the south (66.45°S, 171.8°W) and north (56.23°S, 172°W) patches. The south patch was replete with all macronutrients, whereas the north patch was nearly depleted of silicate. Using a towed water sampling/measurement system, high resolution...
To investigate CO₂ chemistry in ocean water with greater time-space resolutions, we systems, which have state-of-the-art precision but an order of magnitude or better analysis, for carbon dioxide partial pressures (Pco₂) and total carbon dioxide Pco₂ system was based on equilibration of a CO₂-free carrier gas stream with seawater sample...
The carbon system of the western Arctic Ocean is undergoing a rapid transition as sea ice extent and thickness decline. These processes are dynamically forcing the region, with unknown consequences for CO2 fluxes and carbonate mineral saturation states, particularly in the coastal regions where sensitive ecosystems are already under threat...
The Chukchi Sea is thought to be a globally important sink of atmospheric CO₂ due to the summertime drawdown of surface pCO₂ by phytoplankton and subsequent shelf-to-basin transport of CO₂-enriched subsurface waters into the upper halocline of the Arctic Ocean. Here we show that annually occurring storm-induced mixing events during...
Carbon dioxide (CO₂) fluxes between the ocean and atmosphere on continental margins are difficult to diagnose because these regions experience large variability over spatial and temporal scales spanning meters to basins and hours to years, respectively. In a global sense, continental margins could represent a significant atmospheric CO₂ sink, equivalent...
Rates of net community production (NCP) and air-sea CO₂ flux in the Northeast Pacific subarctic, transition zone and subtropical regions (22°N–50°N, 145°W–152°W) were determined on a cruise in August–September 2008 by continuous measurement of surface values of the ratio of dissolved oxygen to argon (O₂/Ar) and the partial pressure of...
Patterns of primary productivity in the Arctic are expected to change with continued warming, yet productivity measurements are historically limited, both spatially and temporally. An established method of measuring net biological oxygen production, which can be used to estimate net community production (NCP) rates, is with an equilibrated inlet mass...
We use autonomous gas measurements to examine the metabolic balance (photosynthesis
minus respiration) of coastal Antarctic waters during the spring/summer growth season. Our observations
capture the development of a massive phytoplankton bloom and reveal striking variability in pCO₂ and
biological oxygen saturation (ΔO₂/Ar) resulting from large shifts in community metabolism...
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. Paper., 58(3), 241–259.
Wanninkhof, R. (1992), Relationship between wind-speed and gas exchange over
Numerous monitoring efforts are underway to improve understanding of ocean acidification and its impacts on coastal environments, but there is a need to develop a coordinated approach that facilitates spatial and temporal comparisons of drivers and responses on a regional scale. Toward that goal, the California Current Acidification Network (C-CAN)...
Previous work has shown that the Oregon shelf is a sink for atmospheric carbon dioxide (CO₂) during the upwelling season; however, until now, summertime variability in CO₂ exchange and sign of the flux for the rest of the year were unknown. Observations of the partial pressure of CO₂ (pCO₂) in...
We examined high-resolution cross-shelf distributions of particulate organic carbon
(POC) and dissolved O₂ during the upwelling season off the Oregon coast. Oxygen
concentrations were supersaturated in surface waters, and hypoxic in near-bottom
waters, with greatly expanded hypoxic conditions late in the season. Simplified time-dependent
mass balances on cross-shelf integrated concentrations...
Hypoxia is a naturally occurring phenomenon that happens seasonally off the Oregon coast. As a consequence, there has been a great deal of research focused around analyzing the strength and duration of the hypoxic event during the summer season. This paper, however, takes an innovative approach by looking at the...
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Wanninkhof, R, 1992. Relationship between wind speed and gas exchange over the ocean.
Journal of
Modeling elementary chemical reactions in ocean fluid dynamics simulations requires significant computing resources, which can be diminished with model reduction techniques. Submesoscale ocean turbulence and biogeochemical reactions in the ocean occur on approximately the same time scale, 105 seconds. This similarity in time scales indicates a strong coupling between these...
Time-series observations are critical to understand the structure, function, and dynamics of marine ecosystems. The Hawaii Ocean Time-series program has maintained near-monthly sampling at Station ALOHA (22°45′N, 158°00′W) in the oligotrophic North Pacific Subtropical Gyre (NPSG) since 1988 and has identified ecosystem variability over seasonal to interannual timescales. To further...
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Wilson, S. T., Barone, B., Ascani, F., Bidigare, R. R., Church, M. J., Valle, D. A., ...
& Karl, D. M
Recent studies have suggested that the marine contribution of methane from shallow regions and melting marine-terminating glaciers may have been underestimated. Here we report on methane sources and potential sinks associated with methane seeps in Cumberland Bay, South Georgia's largest fjord system. The average organic carbon content in the upper...
Anthropogenic carbon dioxide (CO₂) emissions are acidifying the ocean, affecting calcification rates in pelagic organisms, and thereby modifying the oceanic carbon and alkalinity cycles. However, the responses of pelagic calcifying organisms to acidification vary widely between species, contributing uncertainty to predictions of atmospheric CO₂ and the resulting climate change. At...
As concern grows about the long-term effects of increasing atmospheric CO₂
concentrations, it becomes increasingly important to understand the cycling of carbon
on Earth, particularly in the dynamic marine reservoir. Gas exchange and relatively
rapid ocean mixing times mean that the oceans play a significant role in determining
the atmospheric...
We examined the spatial and temporal variability of stream carbon dioxide (CO₂) and the drivers of these variations in a headwater catchment. To examine temporal variation and drivers, we measured stream and hyporheic pCO₂ at high temporal resolution over 11 months in a 95.9-ha forested headwater catchment in the Western...