Table of Contents

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

This dataset combines the biogeochemical data collected during the Flower Garden Banks Rapid Response Cruise which occurred following the discovery of the localized mortality event.

The CTD (SBE-25) was equipped with 6 4L niskin bottles and was used to measure temperature and salinity. Niskins were used to collect water samples for carbonate chemistry (i.e., DIC and TA), oxygen, and nutrients. Water samples for DIC and TA were collected according to the methods in Dickson et al. (2007), and analyzed at TAMU using a VINDTA 3C. Certified Reference Materials (CRMs) were provided by A. Dickson at Scripps Institute of Oceanography (Dickson et al. 2007) and were used to calibrate for TA and DIC. The reproducibility of these samples was 1.43 ± 1.07 μmol kg-1 for TA and 2.64 ± 1.24 μmol kg-1 for DIC. Dissolved oxygen (DO) was measured using Winkler titrations. After collecting the water from the Niskin into flasks, aliquots of manganese chloride and sodium hydroxide-sodium iodide were added. The titration was performed directly after water collection using sodium thiosulfate; Winkler titration was performed with an amperometric dead-stop endpoint determination with a double platinum electrode. Nutrient samples (nitrate, nitrite, ammonium, phosphate, and silicate) were collected into polycarbonate flasks after filtration through GF/C 0.7-um pore size filters, frozen, and analyzed ashore using standard World Ocean Circulation Experiment (WOCE) segmented flow methodologies using an Astoria Analyzer (Astoria-Pacific) (Gordon 1994 ).

Sampling gaps are reported as "nd" in the dataset.

BCO-DMO Processing:
- renamed fields (removed spaces and units); 
- formatted date column to yyyy-mm-dd (was m/d/yy);
- corrected year value of 2006 to 2016 (in row 128);
- added ISO_DateTime column
- replaced "nan" with "nd" (no data)

NSF Award Abstract:
Coral reefs are ecologically and economically important ecosystems, and are threatened by a variety of global (climate change) and local (overfishing, pollution) stressors. Anthropogenic climate change is increasing the frequency and severity of storms, which can physically damage reef structures and reduce reef health through changes in seawater quality. In August of 2017, Hurricane Harvey caused widespread flooding in southeast Texas when it released more than 50 trillion liters of rain, which then accumulated along the Texas Shelf. This runoff is expected to impact nearby coral reefs in the Flower Garden Banks National Marine Sanctuary (FGBNMS, northwest Gulf of Mexico) via eddies and jets that transport coastal waters offshore. Findings from this project will allow managers to quickly predict whether extreme storm events are likely to induce reef mortality and ecosystem decline due to freshwater accumulation, by tracking of low salinity water masses coupled with microbial community characterization and metrics of coral health. These data are critical to managing coastal ecosystems, including the high coral cover reefs in the FGBNMS, and will help stakeholders (e.g., diving and fishing communities) plan for and minimize disruption to their livelihoods following these storms. Results will be communicated broadly across scientific arenas, in graduate and undergraduate education and training programs, and to the general public through outreach. The investigators have seven 7 square meter 2-D Reef Replicas from 2014 depicting representative FGBNMS reef bottoms, and will construct additional 2-D Reef Replicas from both banks following the arrival of Harvey runoff, allowing the public to directly experience and quantify the effects of Hurricane Harvey on local reefs using quadrats and identification guides. This project will also synergize with NSF REU programs at Boston University and Texas A&M University, providing transformative research experiences for undergraduates. One post-doctoral scholar, four graduate students, a technician and more than 5 undergraduates will be involved in all aspects of the research. All datasets will be made freely available to the public, and will serve as an important set of baselines for future lines of inquiry into the processes by which hurricanes and other extreme storms impact reef health.

Hurricanes and other extreme storm events can decimate coral reefs through wave-driven physical damage. Freshwater runoff from extreme storms is also potentially detrimental to reefs but has received comparatively less attention. This research will provide unprecedented resolution on how hurricanes and other extreme storm events may trigger cascading interactions among water chemistry, declines in metazoan health and shifts in their associated microbial communities, ultimately resulting in coral reef decline. The freshwater runoff initiated by Hurricane Harvey is likely to impact reefs within the FGBNMS, one of the few remaining coral-dominated reefs in the greater Caribbean. The effects of Harvey runoff will be compared to a previously documented storm-driven runoff event that was associated with invertebrate mortality on the same reef system. Sampling seawater chemistry, microbial communities (water column and benthic), and host gene expression and proteomics before, immediately after, and six months after Harvey runoff enters the FGBNMS will allow us to identify commonalities among large-scale freshwater runoff events and track the response of benthic invertebrate health, microbial community diversity, and the trajectory of reef community recovery or decline. The investigators will determine if changes in water chemistry induce pelagic microbial shifts, if microbial communities typically associated with corals and sponges are altered, and whether feedbacks occur between these potential drivers of benthic invertebrate mortality.