Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Related Publications
• Parameters
• Instruments
• Deployments
• Project Information
• Funding

These data were published in Barkley et al., 2018.

This dataset contains information about discrete seawater samples collected from 2012-2016 on Jarvis Island for salinity, nutrients, total alkalinity (TA), and dissolved inorganic carbon (DIC) during each sampling period.

Discrete seawater samples were collected during each sampling period for salinity, nutrients, total alkalinity (TA), and dissolved inorganic carbon (DIC). Temperature and depth were recorded with HOBO temperature loggers (September 2012) and Sensus Ultra dive data loggers (2015-2016). TA and DIC analyses were performed using a Versatile Instrument for the Determination of Total inorganic carbon and titration Alkalinity (VINDTA, Marianda Analytics and Data) and standardized using certified reference materials obtained from Andrew Dickson (Scripps Institution of Oceanography).

Salinity samples were analyzed at WHOI using a Guildline autosal salinometer, and nutrient samples were run at the WHOI Nutrient Analytical Facility.

Seawater samples, and in situ instrument time series were collected during seven expeditions to Jarvis Island between 2008 and 2017, aboard:

• NOAA ship Hi’ialakai (27–29 March 2008, 2–4 April 2010, 3–5 May 2012, 2–5 April 2017)
• Pangaea Exploration S/V Sea Dragon (13–16 September 2012)
• R/V Machias (12–15 November 2015)
• NOAA ship Oscar Elton Sette (17–23 May 2016)

Research activities and sample collection were conducted under U.S. Fish and Wildlife Service Pacific Reefs National Wildlife Refuge Complex Research and Monitoring Special Use Permits

• 12521-10001 (effective date: 15 Jan 2010; expiration date: 30 May 2010)
• 12521-12001 (effective date: 7 Feb 2012; expiration date: 31 Dec 2012)
• 12521-12005 (effective date: 29 Aug 2012; expiration date: 30 June 2014)
• 12521-14001 (effective date: 1 Jan 2015; expiration date: 31 Dec 2015)
• 12513-15001 (effective date: 11 Nov 2015; expiration date: 31 Dec 2015)

and in compliance with Presidential Proclamation 8336.

Full CO2 system parameters were calculated from temperature, salinity, TA, and DIC using CO2SYS with the constants of Mehrbach et al. (1973) refit by Dickson and Millero (1987). Nutrient and carbonate chemistry values were consistent down to 20 m depth, and samples collected between 0 m and 20 m were averaged.

BCO-DMO processing:

• Added ISO_DateTime_UTC column
• Updated column headers
• Standardized the format of columns "date_UTC" and "time_UTC"

NSF Award Abstract:
Ocean warming kills corals and efforts are underway to identify and protect coral reefs that may withstand the projected 21st century rise in tropical ocean temperatures. Coral reefs in the central equatorial Pacific (CEP) have been exposed to episodes of extreme warmth every 3-7 years for centuries, if not millennia, yet remain highly productive ecosystems. Initial data obtained by the investigator from stress signatures archived in the skeletons of long lived coral species, suggests that CEP reefs lose their symbiotic algae or bleach, sometimes severely, during warm episodes. The observation that CEP reefs bleach repetitively yet remain productive implies uncommon resilience to ocean warming. The investigator will use laboratory experiments and field observations to validate skeletal records of historical bleaching. A successful outcome will provide novel and valuable insights into the resilience of the CEP reefs and a new tool with which to identify thermally tolerant coral reef ecosystems across the tropics. Additionally, this project includes mentorship of a postdoc and six undergraduate or high school students, outreach through presentations and media, and expansion of publically available software for coral stress band analysis.

Ocean warming projections indicate severe impacts to coral reefs will occur on an annual basis within the next few decades. Consequently, a coordinated effort is underway to identify reefs that might survive these changes. The investigator will test the hypothesis that such reefs exist at the epicenter of influence of the El Niño-Southern Oscillation (ENSO), where strong inter-annual temperature variability creates conditions conducive for the development of thermal resilience. The project uses laboratory-based bleaching experiments and actual stress signatures accreted by wild corals during the 2015 El Niño to validate signatures of historical bleaching archived in the skeletons of massive reef building corals. In addition the investigator will use new, long cores from the CEP to build a robust dataset of historical bleaching back to the 1800's. A successful outcome will increase confidence in the interpretation of skeletal stress bands as quantitative bleaching proxies and enable the reconstruction of the history of coral reef bleaching and recovery in the CEP.