By Phil Hartmeyer, NOAA Ocean Exploration
ACUA Individual Associate Member
Study of the human connection to the sea, rivers, and lakes has progressively moved into deeper waters thanks to multidisciplinary interests, developments in technology, and exploration-focused missions. NOAA Ocean Exploration is a leader in this space, and, together with partners, works to explore and uncover this connection in deep-ocean and poorly-understood environments.
Multi-disciplinary interests have progressively converged on maritime heritage sites as places to study a variety of scientific and management interests. To quote Dr. Leila Hamdan, these ‘islands of biodiversity’ are being studied further in deepwater in increasing numbers. Microbial, chemical, oceanographic, geologic, and biological studies can appropriately tier atop of traditional maritime heritage discovery and characterization missions. One future direction of deepwater archeology works to advance the research on how environmental variables affect site preservation and the interactions of maritime heritage with the environment. NOAA Ocean Exploration is currently evaluating how to best operationalize sampling these ocean exploration variables and maximize this capability to benefit many ocean science disciplines.
| High-Priority Exploration Variables | Maritime Heritage Application |
|---|---|
| Species-specific and general biomass, density, distribution, diversity and abundance: microbes, plankton, invertebrates, fish, megafauna, marine mammals, meio- and macrofauna | To understand the biological footprint and role of maritime heritage sites in ecology and environment, and the role biology (particularly microbes) play in site formation processes |
| Dissolved oxygen | Oxygen levels affect the rate of organic deterioration, corrosion rates and microbial activity |
| Distribution and cover of habitats: Mud volcanoes, cold seeps, vent communities, cold water/deep-sea coral communities, general living habitats, unique and sensitive communities | Maritime heritage sites occur in all benthic habitats, offering potential for comparative analysis between sites, and comparative analysis to parallel habitats absent of maritime heritage |
| Global seafloor mapping and seafloor composition (substrate) | Understanding substrate type can inform degree of maritime heritage site preservation and future site deterioration processes |
| Particulate organic matter, dissolved organic carbon, heterotrophic and chemoautotrophic carbon | Understanding how sites are affecting the local carbon cycle |
| Inorganic macronutrients, nitrate/nitrite, silicate, and phosphate | Understanding how chemicals emitted by maritime heritage sites are affecting local biological communities, and site deterioration rates |
| Sea surface and subsurface salinity and temperature | Salinity and temperature affect the rate of maritime heritage deterioration and corrosion. Comparative studies of these variables help explain differences in levels of site preservation in the deep ocean |
| Surface and subsurface currents | Subsurface currents can introduce conditions like scour, substrate embedding and sedimentation and affect biological growth |
| Carbonate chemistry: Dissolved inorganic carbon, pH, alkalinity, and redox | Carbonate chemistry affects the degree and rate of maritime heritage deterioration. Comparative studies help explain differences in levels of historic preservation of sites in the deep sea |
| Anthropogenic impacts: Microplastic abundance, size, distribution, and diversity and anthropogenic impacts that may have altered biological communities | Given maritime heritage sites can be proud off the seafloor, they can be damaged by deep-sea fishing practices, and collect marine debris whose effect on local biological communities can be studied |
| Inorganic macronutrients, nitrate/nitrite, silicate, and phosphate | Understanding how chemicals emitted by maritime heritage sites are affecting local biological communities, and site deterioration rates |
| Sea surface and subsurface salinity and temperature | Salinity and temperature affect the rate of maritime heritage deterioration and corrosion. Comparative studies of these variables help explain differences in levels of site preservation in the deep ocean |
| Surface and subsurface currents | Subsurface currents can introduce conditions like scour, substrate embedding and sedimentation and affect biological growth |
| Carbonate chemistry: Dissolved inorganic carbon, pH, alkalinity, and redox | Carbonate chemistry affects the degree and rate of maritime heritage deterioration. Comparative studies help explain differences in levels of historic preservation of sites in the deep sea |
| Anthropogenic impacts: Microplastic abundance, size, distribution, and diversity and anthropogenic impacts that may have altered biological communities | Given maritime heritage sites can be proud off the seafloor, they can be damaged by deep-sea fishing practices, and collect marine debris whose effect on local biological communities can be studied |
Table 1. A sublist of the 16 high priority ocean exploration variables identified in Egan, et. al (2021) and applications that would advance understanding of maritime heritage sites.
Access has always been a part of the challenge in archaeology and a metric for the discipline’s success: access to the past, to each other, and to many voices. Deepwater archaeology (>200m water depth) is often executed off larger research platforms that can only accommodate several scientists among the engineers, technicians, mappers, and ship crew onboard. NOAA Ocean Exploration has created tools and opportunities to make access more equitable including telepresence-enabled exploration, where deep-sea archaeology missions, like geophysical mapping surveys and remotely operated vehicle (ROV) dives, are broadcast live around the world. Telepresence is all about prioritizing access and allows our communities to explore together, bringing sites like the USS Yorktown, sunk in 5200 meters of water, to every living room or device with an internet connection (Fig 1).
“Ocean exploration is about making discoveries, searching for things that are unusual and unexpected. As the first step in the scientific process, the rigorous observations and documentation of biological, chemical, physical, geological, and archaeological aspects of the ocean gained from exploration set the stage for future research and decision-making” (Why do we explore the ocean?). NOAA Ocean Exploration is dedicated to exploring the unknown ocean, unlocking its potential through scientific discovery, technological advancements, and data delivery. The best part? It’s easy to get involved.
For the next several years NOAA Ocean Exploration is leading a multifaceted science campaign called “Beyond the Blue: Illuminating the Pacific” designed to raise collective knowledge, understanding, and appreciation of deep ocean waters in the Pacific Islands region. Success relies on coordinated mapping and exploration expeditions, data management and sharing, strategic partnerships, and outreach and engagement. Alongside many diverse partners, including NOAA’s Office of Marine and Aircraft Operations and the Ocean Exploration Cooperative Institute, NOAA Ocean Exploration funds expeditions on NOAA Ship Okeanos Explorer, Ocean Exploration Trust’s Exploration Vessel Nautilus, and through the office’s Notice of Funding Opportunity. For 2026, Okeanos Explorer efforts will focus around Hawaii, the Pacific Islands Heritage Marine National Monument, American Samoa, and the Cook Islands (Fig 2).
Underscored when operating in remote places, community-driven archaeology maximizes collaborative potential, forging connections with multidisciplinary professionals, students, local communities, and the public while uncovering, together, stories of our shared past. Enabled by telepresence, abundant opportunities exist to join NOAA’s shore-based science team to follow – and contribute to each expedition. Exploration generates lots of data (geophysical, hydrographic, high definition photos and video, and others), and for current or future students, there is an existing inventory of archaeological site data that needs characterization and research. Similarly, the campaign allows our archaeology and history communities to make ROV dive target and exploration area suggestions. Those interested are encouraged to email archaeology.oceanexploration@noaa.gov to learn more about getting involved in NOAA Ocean Exploration archaeology.
Categorised in: Deep Thoughts