Underway surface seawater and marine boundary layer observations made from the Alaska Marine Highway System M/V Columbia from October 2017 to October 2018


From October 2017 to October 2018, underway surface water measurements were collected from the Alaska Marine Highway System M/V Columbia during 81 service route transits. The service route of the Columbia included the ports of Sitka, Juneau, Haines, Skagway, Wrangell, Petersburg, and Ketchikan in southeast Alaska, and between Ketchikan and Bellingham, WA. The vessel sailed from Ketchikan every Wednesday, arrived in Bellingham on Friday, and returned to Ketchikan on Sunday. Measurements of temperature, salinity, dissolved oxygen content, and CO2 partial pressure were made every 2 mins on seawater drawn into the vessel from a ~2 m intake. Seawater was delivered from the intake to analytical equipment on the car deck using a AMT 1/2 HP pump (4295-98). Temperature and salinity data were collected using a Sea-Bird SBE 45 MicroTSG Thermosalinograph, and intake temperature measured using a SBE 38 Digital Oceanographic Thermometer. Dissolved oxygen content was determined using an Aanderaa 4330F that had undergone multipoint calibration. CO2 measurements were made using a General Oceanics 8050 (GO8050) pCO2 Measuring System. All data streams, including GPS information from an antenna and atmospheric pressure from a Druck barometer positioned on the foredeck, were captured by the GO8050 control computer. Atmospheric CO2 measurements were also made using the GO8050 on unaltered marine air drawn to the system through an intake located on the foredeck. The CO2 measurement scheme involved the analysis of four gas standards of known CO2 content (150 ppm, 349 ppm, 449 ppm, and 850 ppm; Praxair), 12 analyses atmospheric CO2, and 240 seawater CO2 measurements in a cycle that was repeated every 8.5 hours. The seawater and atmospheric CO2 analyses were run in a sequence of 3 atmospheric measurements and 60 seawater measurements that was repeated 4 times between standardization. This project was supported by the Tula Foundation and Alaska Ocean Observing System, and was a collaborative effort between the Hakai Institute, University of Washington Joint Institute for the Study of the Atmosphere and Ocean/NOAA Pacific Marine Environmental Laboratory, State of Alaska Department of Transportation, University of Alaska Southeast Alaska Coastal Rainforest Center, and the Alaska Ocean Observing System.

Access and Use

Licence: Creative Commons Attribution 4.0

Data and Resources



Dataset extent

Metadata Reference Date(s) January 13, 2022 (Revision)
January 24, 2022 (Publication)
Data Reference Date(s) April 25, 2019 (Publication)
Frequency of Update As Needed

Responsible Party 1
Wiley Evans
Hakai Institute
  • Custodian
  • Owner
  • Point of Contact
  • Principal Investigator
Responsible Party 2
Hakai Institute
  • Distributor
  • Resource Provider

Field Value
Ocean Variables
  • Inorganic Carbon
  • Other
Climate Variables Inorganic Carbon
Scope Dataset
Status Completed
Topic Category oceans
Maintenance Note Generated from https://cioos-siooc.github.io/metadata-entry-form
Spatial Extent [[[-140.68082679, 46.98536693], [-119.96438849, 46.98536693], [-119.96438849, 59.31669647], [-140.68082679, 59.31669647], [-140.68082679, 46.98536693]]]
North Bounding Latitude 59.31669647
South Bounding Latitude 46.98536693
East Bounding Longitude -119.96438849
West Bounding Longitude -140.68082679
Vertical Extent
Default Locale English
Citation identifier
Included in Data Catalogue
Included in Data Catalogue 1
Hakai Data Catalogue
Science on the Coastal Margin