A compiled data product of profile, discrete biogeochemical measurements from 35 individual cruise data sets collected from a variety of ships in the southern Salish Sea and northern California Current System (Washington state marine waters) from 2008-02-04 to 2018-10-19

by Simone R. Alin¹, Jan Newton², Dana Greeley¹, Beth Curry², Julian Herndon³, Alex Kozyr⁴ and Richard A. Feely¹

¹Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, Washington, USA
²Applied Physics Laboratory, University of Washington, Seattle, Washington, USA
³Cooperative Institute for Climate, Ocean, and Ecosystem Studies, University of Washington, Seattle, Washington, USA
⁴National Centers for Environmental Information, National Oceanic and Atmospheric Administration, Silver Spring, Maryland, USA

OCADS Project Metadata Page        Database Files (Please see Copyright and Fair Data Use information at the bottom of this page)       

Figure caption

Map of study area, with regions coded using different symbols and cruise station numbers included. “Puget Sound” cruises cover these areas of the southern Salish Sea: Admiralty Reach (red squares), Hood Canal (blue circles), Whidbey Basin (purple diamonds), and Main Basin and South Sound (green triangles, with South Sound stations being 34–38). “Sound-to-Sea” cruises occupied some or all of the stations along the red line (white circles). In some publications, these station numbers are given with a preceding “P”—the station numbers are identical, however (see the NANOOS Salish Cruise app Map tab for full station name information: http://nvs.nanoos.org/CruiseSalish).

Abstract

Acidification patterns in coastal and estuarine environments are challenging to characterize and attribute using moored time-series alone because lateral, depth, and time patterns are complex and have multiple drivers, including circulation, biology, regional weather, and large-scale climate oscillations. Cruise time-series can provide spatial context to data sets with higher temporal resolution, provide invaluable validation for numerical simulations, and frame biological experiments and observations with information about relevant environmental complexity. This time-series of 35 cruise data sets (See Table below) extending through the southern Salish Sea and into Washington’s northern coastal waters spans the years 2008–2018, including strong ocean condition anomalies, with sampling depths from the seawater surface to near-bottom water masses. Two predominant sampling patterns are present across the cruises: 1) Puget Sound cruises sampled all basins within the sound and across the sill at its inlet (Admiralty Reach). These cruises have recurred regularly in April, July, and September since 2014. 2) “Sound-to-Sea” cruises, associated with servicing the Ćháʔba· ocean acidification mooring off La Push, Washington, sample at a suite of CTD stations located between Seattle (located just east of where the Main Basin line ends on the map) and the mooring site off the coast, occurring most frequently in May and October. A subset of stations (7, 22, and 28) belong to both Puget Sound and Sound-to-Sea cruises. Biological sample collection has also been conducted regularly since 2014 at a subset of stations (in the Salish Sea: 4, 8, 12, 22, 28, 38, 402, and on the coast at station 381), although biological data are not included in the data products described here. Observations included in the Salish cruise data product are bottle sample analyses of total alkalinity, dissolved inorganic carbon, nutrient (nitrate, nitrite, ammonium, phosphate, silicate), and oxygen content (µmol per kg units); and CTD sensor measurements of temperature, salinity (via conductivity), and oxygen content at bottle sample depths where Niskin bottles collected seawater. Oxygen and nutrient data are also provided in concentration units (mg per L) to facilitate data uptake by biology end users, and oxygen data are provided in mL per L units as well. This data product captures the long-lasting effects of the Northeast Pacific marine heatwave of 2013–2015 and the El Niño of 2015–2016 on the temperature profiles of the southern Salish Sea, with contemporaneous changes in inorganic carbon, oxygen, and nutrient content. Further details on methods and findings from the Salish cruise time-series are presented in publications. This time-series from cruises in Washington’s estuarine and coastal waters is known collectively as “the Salish cruises,” and end users are encouraged to use the most recent full data product files available via the Database Files link above, as the individual cruise data files linked in Table 1 may not have received all QC updates described in the Alin et al. ESSD publication below. Users can also access full-resolution data (0.5 db depth bins) from CTD downcasts corresponding to the CTD upcast data collected with discrete bottle samples for Salish cruises, including those dating back to 1998, at http://nvs.nanoos.org/CruiseSalish.
Three subsets of the data product are available on the Index page accessed by clicking the Database Files link above the map:
1) Filename “SalishCruise_dataProduct_2008to2018_09202023_CO2calcs.csv” contains the smallest subset of the data product, consisting of 3971 complete records of DIC, TA, T, S, O2, and nutrient measurements with the highest quality QC flags (QC=2, or “acceptable”), ready for calculations of the full carbonate system; this file is recommended for end users without strong familiarity with QCing or interpolating biogeochemical data.
2) Filename “SalishCruise_dataProduct_2008to2018_09202023_questNut.csv” contains additional samples with nutrient data that require further QC attention (total of 4021 paired observations); all other data have “acceptable” QC flags (=2).
3) Filename “SalishCruise_dataProduct_2008to2018_09202023_allData.csv” contains the most complete version of the Salish cruise data product, including all data with “questionable” QC flags (=3) and data gaps for users with the capacity for or interest in interpolating to fill data gaps. The total number of observations in this file is 7525.
An Excel file with updated metadata, including a tab detailing changes since the previous version of the data product on the NCEI page, is also available via the Index page (“SalishCruise_dataProduct_2008to2018_metadata_09202023.xlsx”).