Ocean Chemistry of Greenhouse Gases Group

Peter G. Brewer, Principal Investigator

The Ocean Chemistry of Greenhouse Gases is a long-standing MBARI project that first began in 1996 with a simple experiment on an ROV to make gas hydrates in the natural marine environment. The immediate success of this first experiment quickly led to other experiments and the project has continued to evolve over time. At its heart, the project is based upon a simple premise: use MBARI’s advanced technology and ROV platforms to investigate the physical and environmental chemistry of carbon dioxide and methane, which are two of the most prominent and important gases affecting Earth’s changing climate and the health of the ocean. This premise has not only proved successful, it led to a variety of different experiments, discoveries and technology developments.

The project began with a series of experiments investigating the hydrate formation process. This effort required the development of new hardware to transport pressurized gases (e.g., methane, propane, ethane, etc.) and compressed liquids (carbon dioxide) into the deep sea onboard an ROV. Learning how to make controlled releases and conduct in situ synthesis experiments proved both technologically challenging and scientifically rewarding as this work led to new understandings of the clathrate hydrate formation processes.

hydrate synth expt 1

The technology developed for making artificial gas hydrates in the deep sea later enabled investigation of the impact of deep ocean CO2 sequestration. Initially, the project focused on questions related to CO2 hydrate formation, long-term hydrate stability and measurements of hydrate dissolution rates. When this work attracted the interest of biologists who were concerned about the impact of high CO2 levels and low pH on the animals in the deep sea, we partnered with the Barry lab to conduct studies of benthic ecology. This work would eventually lead to the FOCE project.

benthic CO2 work 2

In order to more fully understand the hydrate synthesis process, we developed the first deep ocean Raman in situ spectrometer (DORISS) to allow spectroscopic measurements of the composition and crystal structure of the hydrates formed. Following our successes with synthetic hydrates, we then pursued the investigation of naturally occurring gas hydrates at Eel Canyon, Hydrate Ridge and Barkley Canyon.

Laser on hydrate outcrop

The work with naturally occurring gas hydrates led to physical chemistry studies of the associated gas and oil seeps. With the laser Raman spectrometer we were able to measure the gas composition in situ and study the release of light-weight hydrocarbon gases from rising droplets of oil. In order to further understand the chemistry of these processes, we performed a series experiments to investigate the loss of methane and other gases from small scale releases of surrogate oils in Monterey Bay.

laser on oi and gas in glass push core

More recently, with the development of a pore-water sampling probe, we have used DORISS to make in situ measurments of the interstitial fluids in reducing sediments. The laser Raman spectrometer allows the determination of sulfate, hydrogen sulfide, bisulfide, and dissolved methane in these fluids. When the concentration of hydrogen sulfide is sufficiently high, we can estimate the pore-water pH from the ratio of the hydrogen sulfide and bisulfide peaks.

Pore water probe tripod



Upper-ocean systems
Acoustical ocean ecology
Acoustic instruments
Acoustic fingerprinting
Acoustic community ecology
Acoustics in the news
Biological oceanography
Global modes of sea surface temperature
Krill hotspots in the California Current
Nitrate supply estimates in upwelling systems
Chemical sensors
Chemical data
Land/Ocean Biogeochemical Observatory in Elkhorn Slough
Listing of floats
SOCCOM float visualization
Periodic table of elements in the ocean
Biogeochemical-Argo Report
Profiling float
Interdisciplinary field experiments
Ecogenomic Sensing
Genomic sensors
Field experiments
Harmful algal blooms (HABs)
Water quality
Environmental Sample Processor (ESP)
ESP Web Portal
In the news
Ocean observing system
Midwater research
Midwater ecology
Deep-sea squids and octopuses
Food web dynamics
Midwater time series
Respiration studies
Zooplankton biodiversity
Seafloor processes
Revealing the secrets of Sur Ridge
Exploring Sur Ridge’s coral gardens
Life at Sur Ridge
Mapping Sur Ridge
Biology and ecology
Effects of humans
Ocean acidification, warming, deoxygenation
Lost shipping container study
Effects of upwelling
Faunal patterns
Previous research
Technology development
High-CO2 / low-pH ocean
Benthic respirometer system
Climate change in extreme environments
Station M: A long-term observatory on the abyssal seafloor
Station M long-term time series
Monitoring instrumentation suite
Sargasso Sea research
Antarctic research
Geological changes
Arctic Shelf Edge
Continental Margins and Canyon Dynamics
Coordinated Canyon Experiment
CCE instruments
CCE repeat mapping data
Monterey Canyon: A Grand Canyon beneath the waves
Submarine volcanoes
Mid-ocean ridges
Magmatic processes
Volcanic processes
Explosive eruptions
Hydrothermal systems
Back arc spreading ridges
Near-ridge seamounts
Continental margin seamounts
Non-hot-spot linear chains
Eclectic seamounts topics
Margin processes
Hydrates and seeps
California borderland
Hot spot research
Hot-spot plumes
Magmatic processes
Volcanic processes
Explosive eruptions
Volcanic hazards
Hydrothermal systems
Flexural arch
Coral reefs
ReefGrow software
Eclectic topics
Submarine volcanism cruises
Volcanoes resources
Areas of study
Bioluminescence: Living light in the deep sea
Microscopic biology research
Open ocean biology research
Seafloor biology research
Automated chemical sensors
Methane in the seafloor
Volcanoes and seamounts
Hydrothermal vents
Methane in the seafloor
Submarine canyons
Earthquakes and landslides
Ocean acidification
Physical oceanography and climate change
Ocean circulation and algal blooms
Ocean cycles and climate change
Past research
Molecular ecology
Molecular systematics
SIMZ Project
Bone-eating worms
Gene flow and dispersal
Molecular-ecology expeditions
Ocean chemistry of greenhouse gases
Emerging science of a high CO2/low pH ocean
Brewer, P.G., Peltzer, E.T., Lage, K., (2022). Life at low Reynolds number Re-visited: The efficiency of microbial propulsion. Deep Sea Research Part I: Oceanographic Research Papers, 185: 1-5. https://doi.org/10.1016/j.dsr.2022.103790
Goyet, Catherine, Davis, Daniel L., Peltzer, Edward T., Brewer, Peter G., (1995). Development of improved space sampling strategies for ocean chemical properties: Total carbon dioxide and dissolved nitrate. Geophysical Research Letters, 22: 945-948.
Brewer, Peter G., Goyet, Catherine , Friederich, Gernot, (1997). Direct observation of the oceanic CO2 increase revisited. Proceedings of the National Academy of Sciences of the USA, 94: 8308-8313.
Full publications list