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Title: A decade of marine inorganic carbon chemistry observations in the northern Gulf of Alaska – insights into an environment in transition
Abstract. As elsewhere in the global ocean, the Gulf of Alaska is experiencing the rapid onset of ocean acidification (OA) driven by oceanic absorption of anthropogenic emissions of carbon dioxide from the atmosphere. In support of OA research and monitoring, we present here a data product of marine inorganic carbon chemistry parameters measured from seawater samples taken during biannual cruises between 2008 and 2017 in the northern Gulf of Alaska. Samples were collected each May and September over the 10 year period using a conductivity, temperature, depth (CTD) profiler coupled with a Niskin bottle rosette at stations including a long-term hydrographic survey transect known as the Gulf of Alaska (GAK) Line. This dataset includes discrete seawater measurements such as dissolved inorganic carbon and total alkalinity, which allows the calculation of other marine carbon parameters, including carbonate mineral saturation states, carbon dioxide (CO2), and pH. Cumulative daily Bakun upwelling indices illustrate the pattern of downwelling in the northern Gulf of Alaska, with a period of relaxation spanning between the May and September cruises. The observed time and space variability impart challenges for disentangling the OA signal despite this dataset spanning a decade. However, this data product greatly enhances our understanding of seasonal and interannual variability in the marine inorganic carbon system parameters. The product can also aid in the ground truthing of biogeochemical models, refining estimates of sea–air CO2 exchange, and determining appropriate CO2 parameter ranges for experiments targeting potentially vulnerable species. Data are available at https://doi.org/10.25921/x9sg-9b08 (Monacci et al., 2023).  more » « less
Award ID(s):
2322806 1656070
PAR ID:
10519761
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Copernicus Publications
Date Published:
Journal Name:
Earth System Science Data
Edition / Version:
1
Volume:
16
Issue:
1
ISSN:
1866-3516
Page Range / eLocation ID:
647 to 665
Subject(s) / Keyword(s):
ocean acidification, pCO2, pH
Format(s):
Medium: X Other: pdf
Sponsoring Org:
National Science Foundation
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