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Conductivity, Temperature, Depth (CTD)

A Conductivity (salinity), Temperature, Depth (CTD) sensor is a key instrument on ocean acidification research cruises. CTD measurements paint a picture of salinity and temperature from surface to seafloor. Temperature and salinity influence water movement, activity by marine life, and water chemistry throughout the ocean. The CTD is linked with a Niskin bottle rosette (pictured). This collector takes water samples at many depths, providing a snapshot of the whole water column. This expands our sampling below surface waters that are continuously monitored by buoys and moorings in our network. Scientists deploy the CTD rosette at every monitoring station during the cruise.

Water Quality

Dissolved Inorganic Carbon (DIC)

The partial pressure of CO2 (pCO2) tells us how much carbon dioxide is in seawater. Sampling on ocean acidification research cruises expands an important time-series of marine carbon dioxide levels. This information helps us understand ocean carbonate chemistry and biological productivity in the region. On ECOA-3, NOAA’s Atlantic Oceanographic and Meteorological Laboratory (AOML) measured pCO2 using an underway system that continuously takes high-quality measurements during the cruise.

Water Chemistry

Partial Pressure of CO2 (pCO2)

Increases in carbon dioxide (known as CO2) in the atmosphere drive corresponding increases in dissolved CO2 within the surface waters of our ocean. This dissolved CO2 reacts with seawater to form carbonic acid (H2CO3). Carbonic acid breaks apart to form bicarbonate ions (HCO3–) and hydrogen ions (H+). Hydrogen ions (H+) act like free agents. And while the ocean is not acidic, these free agent hydrogen ions cause the seawater to become more acidic. We measure this using pH (H represents hydrogen ions). The free agent hydrogen ions also react with carbonate ions (CO32-) to form bicarbonate (HCO3–), making carbonate ions relatively less abundant. Next, find out why this matters next.

Water Chemistry
Photo Credit: Joe Salisbury (UNH)

Total Alkalinity & pH (TA, pH)

When the ocean absorbs carbon dioxide, chemical reactions create hydrogen ions that act like free agents, able to react with other components in the seawater. Two ways we track ocean acidification are through pH and total alkalinity (TA). pH is a measure of how many free hydrogen ions are in the seawater. More carbon dioxide in the ocean creates more of these free agents, causing lower pH (more acidic). Alkalinity is the ocean’s buffering system against increasing acidity. Total alkalinity is a measure of the concentration of buffering molecules like carbonate and bicarbonate in the seawater that can neutralize acid. Researchers aboard ocean acidification research cruises measure pH and TA along the seaboard.

Water Chemistry

Oxygen (O2)

Oxygen is a core measurement taken on coastal and ocean acidification research cruises. Like animals on land, marine life requires sufficient oxygen to live. Ocean oxygen is considered a co-stressor to ocean acidification. Both low oxygen and acidification increase stress on marine life, and they often occur at the same times and places, creating a greater burden for socio-economically important species. On ECOA-3, researchers from the University of Miami researched more about how ocean biogeochemistry controls oxygen saturation. Oxygen is measured onboard using the Winkler titration method.

Water Chemistry
Harmful Al

Harmful Algal Blooms & Other Protists

Oxygen is a core measurement taken on coastal and ocean acidification research cruises. Like animals on land, marine life requires sufficient oxygen to live. Ocean oxygen is considered a co-stressor to ocean acidification. Both low oxygen and acidification increase stress on marine life, and they often occur at the same times and places, creating a greater burden for socio-economically important species. On ECOA-3, researchers from the University of Miami researched more about how ocean biogeochemistry controls oxygen saturation. Oxygen is measured onboard using the Winkler titration method.

Ecosystem Health
Sediment demo
Image Credit: NOAA OAP

Sediment

Sediments contribute importantly to biogeochemical cycles and remain understudied. On ECOA-3, scientists from the University of Connecticut, Avery Point collected sediments from the seafloor to better understand carbon exchange between seawater and seafloor with the help of bacteria, plankton and other marine life. This was the first time for these in depth sediment analyses on an ECOA cruise.
Take a deep dive with the sediment corer from ECOA-3 >
Ecosystem Health
Satellite image of Chesapeake Bay, estuaries, Washington DC, Baltimore MD.
Image Credit: NASA

Nutrients

Nitrate, nitrite, ammonium, phosphate and silicate are major inorganic nutrients that control primary production and carbon movement in the ocean. Together with the measurements of inorganic carbon, researchers will estimate the effect of riverine input, air-sea CO2 exchange, biological productivity, and carbon exchange on the coastal carbon dynamics.

Ecosystem Health
Image Credit: NASA

Ocean Optics

Satellites complement monitoring in the water. Measurements of light in the ocean collected during daylight hours while sampling water directly enable comparisons between the different types of data. This work supports the calibration and validation of sensors on join NOAA and NASA supported satellites. Furthermore, this information helps validate satellite-based sensors for ocean carbon and better quantify the relationships between salinity and organic (life-based) and inorganic carbon. Some of the parameters collected are colored dissolved organic matter (CDOM), chlorophyll (green pigments from plankton), and salinity. 
Verification of Observations
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ADAPTING TO OCEAN ACIDIFICATION

The NOAA Ocean Acidification Program (OAP) works to prepare society to adapt to the consequences of ocean acidification and conserve marine ecosystems as acidification occurs. Learn more about the human connections and adaptation strategies from these efforts.

Adaptation approaches fostered by the OAP include:

FORECASTING

Using models and research to understand the sensitivity of organisms and ecosystems to ocean acidification to make predictions about the future, allowing communities and industries to prepare

MANAGEMENT

Using these models and predictions as tools to facilitate management strategies that will protect marine resources and communities from future changes

TECHNOLOGY DEVELOPMENT

Developing innovative tools to help monitor ocean acidification and mitigate changing ocean chemistry locally

REDUCING OUR CARBON FOOTPRINT

50 more ways to reduce your carbon footprint >

On the Road

Drive fuel-efficient vehicles or choose public transportation. Choose your bike or walk! Don't sit idle for more than 30 seconds. Keep your tires properly inflated.

With your Food Choices

Eat local- this helps cut down on production and transport! Reduce your meat and dairy. Compost to avoid food waste ending up in the landfill

With your Food Choices

Make energy-efficient choices for your appliances and lighting. Heat and cool efficiently! Change your air filters and program your thermostat, seal and insulate your home, and support clean energy sources

By Reducing Coastal Acidification

Reduce your use of fertilizers, Improve sewage treatment and run off, and Protect and restore coastal habitats

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TAKE ACTION WITH YOUR COMMUNITY

You've taken the first step to learn more about ocean acidification - why not spread this knowledge to your community?

Every community has their unique culture, economy and ecology and what’s at stake from ocean acidification may be different depending on where you live.  As a community member, you can take a larger role in educating the public about ocean acidification. Creating awareness is the first step to taking action.  As communities gain traction, neighboring regions that share marine resources can build larger coalitions to address ocean acidification.  Here are some ideas to get started:

  1. Work with informal educators, such as aquarium outreach programs and local non-profits, to teach the public about ocean acidification. Visit our Education & Outreach page to find the newest tools!
  2. Participate in habitat restoration efforts to restore habitats that help mitigate the effects of coastal acidification
  3. Facilitate conversations with local businesses that might be affected by ocean acidification, building a plan for the future.
  4. Partner with local community efforts to mitigate the driver behind ocean acidification  – excess CO2 – such as community supported agriculture, bike & car shares and other public transportation options.
  5. Contact your regional Coastal Acidification Network (CAN) to learn how OA is affecting your region and more ideas about how you can get involved in your community
       More for Taking Community Action