scholarly journals Carbon cycling in the North American coastal ocean: a synthesis

2019 ◽  
Vol 16 (6) ◽  
pp. 1281-1304 ◽  
Author(s):  
Katja Fennel ◽  
Simone Alin ◽  
Leticia Barbero ◽  
Wiley Evans ◽  
Timothée Bourgeois ◽  
...  

Abstract. A quantification of carbon fluxes in the coastal ocean and across its boundaries with the atmosphere, land, and the open ocean is important for assessing the current state and projecting future trends in ocean carbon uptake and coastal ocean acidification, but this is currently a missing component of global carbon budgeting. This synthesis reviews recent progress in characterizing these carbon fluxes for the North American coastal ocean. Several observing networks and high-resolution regional models are now available. Recent efforts have focused primarily on quantifying the net air–sea exchange of carbon dioxide (CO2). Some studies have estimated other key fluxes, such as the exchange of organic and inorganic carbon between shelves and the open ocean. Available estimates of air–sea CO2 flux, informed by more than a decade of observations, indicate that the North American Exclusive Economic Zone (EEZ) acts as a sink of 160±80 Tg C yr−1, although this flux is not well constrained. The Arctic and sub-Arctic, mid-latitude Atlantic, and mid-latitude Pacific portions of the EEZ account for 104, 62, and −3.7 Tg C yr−1, respectively, while making up 51 %, 25 %, and 24 % of the total area, respectively. Combining the net uptake of 160±80 Tg C yr−1 with an estimated carbon input from land of 106±30 Tg C yr−1 minus an estimated burial of 65±55 Tg C yr−1 and an estimated accumulation of dissolved carbon in EEZ waters of 50±25 Tg C yr−1 implies a carbon export of 151±105 Tg C yr−1 to the open ocean. The increasing concentration of inorganic carbon in coastal and open-ocean waters leads to ocean acidification. As a result, conditions favoring the dissolution of calcium carbonate occur regularly in subsurface coastal waters in the Arctic, which are naturally prone to low pH, and the North Pacific, where upwelling of deep, carbon-rich waters has intensified. Expanded monitoring and extension of existing model capabilities are required to provide more reliable coastal carbon budgets, projections of future states of the coastal ocean, and quantification of anthropogenic carbon contributions.

2018 ◽  
Author(s):  
Katja Fennel ◽  
Simone Alin ◽  
Leticia Barbero ◽  
Wiley Evans ◽  
Timotheé Bourgeois ◽  
...  

Abstract. A quantification of carbon fluxes in the coastal ocean and across its boundaries, specifically the air-sea, land-to-coastal-ocean and coastal-to-open-ocean interfaces, is important for assessing the current state and projecting future trends in ocean carbon uptake and coastal ocean acidification, but is currently a missing component of global carbon budgeting. This synthesis reviews recent progress in characterizing these carbon fluxes with focus on the North American coastal ocean. Several observing networks and high-resolution regional models are now available. Recent efforts have focused primarily on quantifying net air-sea exchange of carbon dioxide (CO2). Some studies have estimated other key fluxes, such as the exchange of organic and inorganic carbon between shelves and the open ocean. Available estimates of air-sea CO2 flux, informed by more than a decade of observations, indicate that the North American margins act as a net sink for atmospheric CO2. This net uptake is driven primarily by the high-latitude regions. The estimated magnitude of the net flux is 160 ± 80 Tg C/y for the North American Exclusive Economic Zone, a number that is not well constrained. The increasing concentration of inorganic carbon in coastal and open-ocean waters leads to ocean acidification. As a result conditions favouring dissolution of calcium carbonate occur regularly in subsurface coastal waters in the Arctic, which are naturally prone to low pH, and the North Pacific, where upwelling of deep, carbon-rich waters has intensified and, in combination with the uptake of anthropogenic carbon, leads to low seawater pH and aragonite saturation states during the upwelling season. Expanded monitoring and extension of existing model capabilities are required to provide more reliable coastal carbon budgets, projections of future states of the coastal ocean, and quantification of anthropogenic carbon contributions.


2021 ◽  
Vol 13 (6) ◽  
pp. 2777-2799
Author(s):  
Li-Qing Jiang ◽  
Richard A. Feely ◽  
Rik Wanninkhof ◽  
Dana Greeley ◽  
Leticia Barbero ◽  
...  

Abstract. Internally consistent, quality-controlled (QC) data products play an important role in promoting regional-to-global research efforts to understand societal vulnerabilities to ocean acidification (OA). However, there are currently no such data products for the coastal ocean, where most of the OA-susceptible commercial and recreational fisheries and aquaculture industries are located. In this collaborative effort, we compiled, quality-controlled, and synthesized 2 decades of discrete measurements of inorganic carbon system parameters, oxygen, and nutrient chemistry data from the North American continental shelves to generate a data product called the Coastal Ocean Data Analysis Product in North America (CODAP-NA). There are few deep-water (> 1500 m) sampling locations in the current data product. As a result, crossover analyses, which rely on comparisons between measurements on different cruises in the stable deep ocean, could not form the basis for cruise-to-cruise adjustments. For this reason, care was taken in the selection of data sets to include in this initial release of CODAP-NA, and only data sets from laboratories with known quality assurance practices were included. New consistency checks and outlier detections were used to QC the data. Future releases of this CODAP-NA product will use this core data product as the basis for cruise-to-cruise comparisons. We worked closely with the investigators who collected and measured these data during the QC process. This version (v2021) of the CODAP-NA is comprised of 3391 oceanographic profiles from 61 research cruises covering all continental shelves of North America, from Alaska to Mexico in the west and from Canada to the Caribbean in the east. Data for 14 variables (temperature; salinity; dissolved oxygen content; dissolved inorganic carbon content; total alkalinity; pH on total scale; carbonate ion content; fugacity of carbon dioxide; and substance contents of silicate, phosphate, nitrate, nitrite, nitrate plus nitrite, and ammonium) have been subjected to extensive QC. CODAP-NA is available as a merged data product (Excel, CSV, MATLAB, and NetCDF; https://doi.org/10.25921/531n-c230, https://www.ncei.noaa.gov/data/oceans/ncei/ocads/metadata/0219960.html, last access: 15 May 2021) (Jiang et al., 2021a). The original cruise data have also been updated with data providers' consent and summarized in a table with links to NOAA's National Centers for Environmental Information (NCEI) archives (https://www.ncei.noaa.gov/access/ocean-acidification-data-stewardship-oads/synthesis/NAcruises.html).


2021 ◽  
Author(s):  
Li-Qing Jiang ◽  
Richard A. Feely ◽  
Rik Wanninkhof ◽  
Dana Greeley ◽  
Leticia Barbero ◽  
...  

Abstract. Internally-consistent, quality-controlled data products play a very important role in promoting regional to global research efforts to understand societal vulnerabilities to ocean acidification (OA). However, there are currently no such data products for the coastal ocean where most of the OA-susceptible commercial and recreational fisheries and aquaculture industries are located. In this collaborative effort, we compiled, quality controlled (QC), and synthesized two decades of discrete measurements of inorganic carbon system parameters, oxygen, and nutrient chemistry data from the U.S. North American continental shelves, to generate a data product called the Coastal Ocean Data Analysis Product for North America (CODAP-NA). There are few deep-water (> 1500 m) sampling locations in the current data product. As a result, cross-over analyses, which rely on comparisons between measurements on different cruises in the stable deep ocean, could not form the basis for cruise-to-cruise adjustments. For this reason, care was taken in the selection of data sets to include in this initial release of CODAP-NA, and only data sets from laboratories with known quality assurance practices were included. New consistency checks and outlier detections were used to QC the data. Future releases of this CODAP-NA product will use this core data product as the basis for secondary QC. We worked closely with the investigators who collected and measured these data during the QC process. This version of the CODAP-NA is comprised of 3,292 oceanographic profiles from 61 research cruises covering all continental shelves of North America, from Alaska to Mexico in the west and from Canada to the Caribbean in the east. Data for 14 variables (temperature; salinity; dissolved oxygen concentration; dissolved inorganic carbon concentration; total alkalinity; pH on the Total Scale; carbonate ion concentration; fugacity of carbon dioxide; and concentrations of silicate, phosphate, nitrate, nitrite, nitrate plus nitrite, and ammonium) have been subjected to extensive QC. CODAP-NA is available as a merged data product (Excel, CSV, MATLAB, and NetCDF, https://doi.org/10.25921/531n-c230, https://www.ncei.noaa.gov/data/oceans/ncei/ocads/metadata/0219960.html) (Jiang et al., 2020). The original cruise data have also been updated with data providers' consent and summarized in a table with links to NOAA's National Centers for Environmental Information (NCEI) archives (https://www.ncei.noaa.gov/access/ocean-acidification-data-stewardship-oads/synthesis/NAcruises.html).


Author(s):  
Eli R. Pérez‐Ruiz ◽  
Enrique R. Vivoni ◽  
Enrico A. Yépez ◽  
Julio C. Rodríguez ◽  
David J. Gochis ◽  
...  

2019 ◽  
Vol 11 (9) ◽  
pp. 2677 ◽  
Author(s):  
Miho Ishizu ◽  
Yasumasa Miyazawa ◽  
Tomohiko Tsunoda ◽  
Xinyu Guo

We developed a biogeochemical and carbon model (JCOPE_EC) coupled with an operational ocean model for the North Western Pacific. JCOPE_EC represents ocean acidification indices on the background of the risks due to ocean acidification and our model experiences. It is an off-line tracer model driven by a high-resolution regional ocean general circulation model (JCOPE2M). The results showed that the model adequately reproduced the general patterns in the observed data, including the seasonal variability of chlorophyll-a, dissolved inorganic nitrogen/phosphorus, dissolved inorganic carbon, and total alkalinity. We provide an overview of this system and the results of the model validation based on the available observed data. Sensitivity analysis using fixed values for temperature, salinity, dissolved inorganic carbon and total alkalinity helped us identify which variables contributed most to seasonal variations in the ocean acidification indices, pH and Ωarg. The seasonal variation in the pHinsitu was governed mainly by balances of the change in temperature and dissolved inorganic carbon. The seasonal increase in Ωarg from winter to summer was governed mainly by dissolved inorganic carbon levels.


Polar Record ◽  
1956 ◽  
Vol 8 (52) ◽  
pp. 22-23 ◽  
Author(s):  
P. D. Baird

The Arctic Institute of North America was established in 1945 in two small rooms in McGill University, with a staff consisting of Dr Lincoln Washburn and a secretary, who made up for the lack of equipment and facilities by abundant energy and enthusiasm. Since then the Institute's growth has been considerable, always in the direction of its three main objectives—to form a centre for reference information and study on the North American Arctic, to encourage arctic scientific research in any field, and to disseminate arctic information by means of a journal, other publications, and lectures.


2009 ◽  
Vol 9 (2) ◽  
pp. 7213-7237 ◽  
Author(s):  
S. A. Vay ◽  
S. C. Tyler ◽  
Y. Choi ◽  
D. R. Blake ◽  
N. J. Blake ◽  
...  

Abstract. Radiocarbon samples taken over Mexico City and the surrounding region during the MILAGRO field campaign in March 2006 exhibited an unexpected distribution: (1) relatively few samples (23%) were below the North American free tropospheric background value (57‰) despite the fossil fuel emissions from one of the world's most highly polluted environments; and (2) frequent enrichment well above the background value was observed. Correlate source tracer species and air transport characteristics were examined to elucidate influences on the radiocarbon distribution. Our analysis suggests that a combination of radiocarbon sources biased the "regional radiocarbon background" above the North American value thereby decreasing the apparent fossil fuel signature. These sources included the release of bomb or "hot" radiocarbon sequestered in plant carbon pools via the ubiquitous biomass burning in the region as well as the direct release of radiocarbon as CO2. Plausible large local perturbations include the burning of hazardous waste in cement kilns; medical waste incineration; and emissions from the Laguna Verde Nuclear Power Plant. These observations provide insight into the use of Δ14CO2 to constrain fossil fuel emissions in the megacity environment, indicating that underestimation of the fossil fuel contribution to the CO2 flux is likely wherever biomass burning coexists with urban emissions. Our findings increase the complexity required to quantify fossil fuel-derived CO2 in source-rich environments characteristic of megacities, and have implications for the use of Δ14CO2 observations in evaluating bottoms-up emission inventories and their reliability as a tool for validating national emission claims of CO2 within the framework of the Kyoto Protocol.


2019 ◽  
Vol 12 ◽  
pp. 139-164
Author(s):  
Magdalena Lewandowska

The arrival of the ancestors of the Apaches and Navajo to the North American Southwest, the so-called Apachean migra-tion is one of the most widely discussed issues in American archeology. Since the 19th century, after connections were disco-vered between the Athabaskan language family, potential routes and directions of migration between the Arctic and Subarctic region (inhabited by the Northern Athabaskans) and the Southwest (inhabited by the Southern Athabaskans) began to be con-sidered. During the 1930s, the Edward Sapir’s linguistic research made it possible to determine that the migration flowed from north to south, but this conclusion merely sowed the seed of research on Apachean migration, which has since blossomed with archaeological discoveries from the last 20 or 30 years. Today, we are able to pinpoint what prompted the Athabaskans’ journey; we also know of cultures such as Promontory (around the Great Salt Lake) or Dismal River (Great Plains), which we associate with the presence of the Apachean people on both sides of the Rocky Mountains. Still, many questions remain unanswered, and previous hypotheses are being verified in the light of new discoveries. No less interesting proved the results of research into some auxiliary sciences of archeology: genetics and linguistics, and the analysis of historical sources and oral tradition.The following article aims to introduce the reader to the most important and recent discoveries related to the issue of Apachean migration, and present hypotheses that have recently emerged in the scientific community, both in the context of the migration route itself and arrival in the Southwest, as well as the dates associated with them.


The North American Arctic was one of the last regions on Earth to be settled by humans, due to its extreme climate, limited range of resources, and remoteness from populated areas. Despite these factors, it holds a rich and complex history relating to Inuit, Iñupiat, Inuvialuit, Yupik, and Aleut peoples and their ancestors. The artifacts, dwellings, and food remains of these ancient peoples are remarkably well preserved due to cold temperatures and permafrost, allowing archaeologists to reconstruct their lifeways with great accuracy. Furthermore, the combination of modern Elders’ traditional knowledge with the region’s high-resolution ethnographic record allows past peoples’ lives to be reconstructed to a level simply not possible elsewhere. Combined, these factors yield an archaeological record of global significance—the Arctic provides ideal case studies relating to issues as diverse as the impacts of climate change on human societies, the complex process of interaction between indigenous peoples and Europeans, and the dynamic relationships between environment, economy, social organization, and ideology in hunter-gatherer societies. In this book, each Arctic cultural tradition is described in detail, with up-to-date coverage of recent interpretations of all aspects of their lifeways. Additional chapters cover broad themes applicable to the full range of arctic cultures, such as trade, stone tool technology, ancient DNA research, and the relationship between archaeology and modern arctic communities. The resulting volume, written by the region’s leading researchers, is by far the most comprehensive coverage of North American arctic archaeology ever assembled.


Rangifer ◽  
2005 ◽  
Vol 25 (1) ◽  
pp. 19-30 ◽  
Author(s):  
Knut H. Røed

The classification and colonization of reindeer and caribou (Rangifer tarandus) was assessed from analysis of both proteins, nuclear DNA and mitochondrial DNA. I demonstrate that the current subspecies designations are not compatible with the differentiation at these markers, suggesting that the morphological differences among extant subspecies did not evolve in separate glacial refugia. Thus, morphological differences among extant subspecies probably evolved as adaptive responses to post-glacial environmental changes. An exception to this is the North American woodland caribou, where all three marker systems support a subspecies-specific refugium as the ancestral origin of these animals. Three major mtDNA haplogroups reported, represent three separate origins of the species during the last glaciation. The most influential origin has contributed to the gene pool of all extant subspecies, suggesting the existence of a large and continuous glacial population ranging across extensive areas of tundra in Eurasia and Beringia. The North American tundra forms (R.t. granti and groenlandicus) and the arctic forms (R.t platyrhynchus, R.t pearyi and R.t eogroenlandicus) almost exclusively comprise haplotypes of such an origin. Another small and isolated refugium seems to have arisen in western Eurasia in close connection to the extensive ice sheet that covered Fennoscandia. The two Eurasian subspecies R.t. tarandus and R.t. fennicus appear to have a diphyletic origin as both the putatively small and isolated Eurasian refugium and the large Beringia refugium have contributed to their gene pools. A third distinct and geographically well-defined refugial area was probably located south to the extensive North American continental ice sheet from where the ancestors of the present North American woodland caribou (R.t. caribou) likely originated.Abstract in Norwegian / Sammendrag: Systematisk inndeling og kolonisering av rein (Rangifer tarandus) ble bestemt ved å analysere for variasjon i genetiske markører som proteiner, kjerneDNA og mitokondrieDNA. Dagens oppdeling av rein i underarter viser liten overensstemmelse med variasjonsmønsteret i de undersøkte markørene, noe som viser at de morfologiske forskjellene som karakteriserer dagens underarter ikke har utviklet seg i atskilte refugier i løpet av siste istid. Unntak fra dette er nordamerikansk skogsrein (woodland caribou-R.t. caribou) hvor alle tre markørsystemene indikerer at denne har utviklet seg i et refugium forskjellig fra andre underarter. De tre registrerte hovedhaplogruppene i mitokondrie-DNA representerer tre atskilte opprinnelser av rein i løpet av siste istid. Den mest innflytelsesrike av disse bidro vesentlig til genbanken til alle dagens underarter av rein, noe som tyder på at det under siste istid eksisterte en stor reinpopulasjon med kontinuerlig utbredelse gjennom store deler av tundraen i Eurasia og Beringia. De nordamerikanske tundrareintypene (R.t. granti og R.t. groenlandicus), samt de arktiske typene (R.t. platyrhunchus, R.t. pearyi og R.t. eogroenlandicus) består nærmest utelukkende av haplotyper med denne opprinnelse. Et annet lite og isolert refugium syntes å ha oppstått i Vest-Europa i nærheten av den omfattende isbreen som dekket Fennoskandia. De to europeiske underarter, R.t. tarandus og R.t. fennicus, syntes å ha en todelt opprinnelse med genetisk påvirkning fra både det antatt lille og isolerte refugiet i Eurasia samt fra det store Beringia refugiet. Et tredje geografisk distinkt refugium var antagelig lokalisert sør for den omfattende isbreen i Nord Amerika hvorfra forfedrene til dagens nordamerikanske skogsrein (R.t. caribou) har sin mest sannsynlige opprinnelse.


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