Using the power of innovation to impact the world around us
SIGNALS+ NEWSLETTER SUBSCRIPTION
Stay updated and leverage Signals+ latest insights, information and ideas on Connectivity, Digital Health, Electrification, and Smart Industry.
Thank you for subscribing to ADI Signals+. A confirmation email has been sent to your inbox.
You'll soon receive timely updates on all the breakthrough technologies impacting human lives across the globe. Enjoy!
CloseMONITORING OCEAN ACIDIFICATION AND THE NEED TO FEED A GROWING WORLD
The ocean absorbs about 25% of carbon dioxide (CO2)1 emitted into the atmosphere from fossil fuel burning and other human-related activities. When seawater absorbs CO2, it results in the reduction of the ocean’s pH. This process is called ocean acidification, which has potentially devastating effects on the ocean and humans.
Ocean acidification not only causes significant damage to marine ecosystems but also affects the livelihoods of millions of fishermen and threatens species that supply protein for more than 3.3 billion people.2 Extensive pH monitoring is needed to understand better how acidification impacts shellfish and other fishery species’ viability.
In 2021, Analog Devices, Inc. (ADI) partnered with the Woods Hole Oceanographic Institution (WHOI) to establish the Ocean and Climate Innovation Accelerator (OCIA) in order to accelerate and activate new ocean-based climate change solutions. OCIA is a first-of-its-kind consortium bringing together industry, academia, and philanthropy dedicated to addressing the challenges of climate change, protecting marine life, and preserving the seas. The development of a low cost pH sensor designed for deployment on fishing vessels is just one of the projects that ADI is supporting at WHOI.
WOODS HOLE OCEANOGRAPHIC INSTITUTION
At WHOI, scientists and engineers are committed to understanding all facets of the ocean and its complex connections with Earth’s atmosphere, land, and seas and guiding human stewardship of the planet. WHOI wishes to develop affordable, scalable technologies to better comprehend ocean and climate impact while informing policy. One focus is measuring and monitoring ocean acidification and addressing its effect on fishing, fishermen, and global food insecurity.
AT A GLANCE
ORGANIZATION
WHOI is the world’s largest independent ocean research organization with over 300 scientists and engineers, 100+ students, two large ships, and hundreds of submersibles.
APPLICATION
An out-of-the-box optical sensor for quick, continuous, and high quality in situ pH measurement up to a 300-meter water depth enabled by ADI’s ADPD4101 chip for processing the LED signal and CN0503 time-saving reference design.
CHALLENGE
Create an accurate, low-cost, scalable, automated in situ instrument for measuring ocean pH that requires little training to operate and can be deployed on thousands of fishing gears with fishermen acting in the capacity of citizen scientists.
GOAL
Accurately measure coastal water pH in situ by deploying the low cost pH sensors on fishing gear up to 300-meters in depth and develop a continuously updated weather map of coastal ocean regions. The data obtained from the sensor can be used to make mitigation policies, which might be useful to combat ocean acidification.
MONITORING OCEAN ACIDIFICATION AND THE DECLINE IN MARINE LIFE
Excess human-caused CO2 emissions have resulted in a series of changes in seawater that have already lowered the average surface ocean pH by 0.1 unit (that is, increased water acidity by ~30%) since the onset of the Industrial Revolution.3 In addition, the increase of CO2 in the atmosphere increases air temperature, and the resulting air temperature increase warms the ocean.
Impact of acidification warming on the marine life ecosystem
1- CO2 emissions 2- Direct effects 3- Indirect effects
Acidified oceans cause significant damage to animals with exoskeletons and shells, like corals, oysters, shrimp, and scallops. As the sea becomes more acidic, these creatures struggle to grow and maintain their structures, resulting in reduced growth rates and increased mortality. Ocean acidification disrupts the entire marine web, causing an imbalance of the natural ecosystem, with ripples across the food chain impacting fish and other species that depend on these organisms for food and habitat.5
Living corals in Australia’s Great Barrier Reef have declined by half in only three decades, with a significant decrease in the reef’s fish habitat. Coral bleaching extends over 93% of the reef’s 1,429 miles.6
BILLIONS DEPEND ON MARINE LIFE FOR SUSTENANCE
Decreased pH levels in Earth’s oceans have far-reaching implications for food security worldwide. Nearly one in three people in the world (2.37 billion people) lack access to adequate food and nutrition, while 720 million to 811 million people face hunger.7 A steady supply of healthy shellfish and other seafood products is critically needed to help feed the world’s population, which is growing by 1.1% or 83 million annually.8
According to the United Nations report, “The State of World Fisheries and Aquaculture,” fish and fisheries products are recognized as some of the healthiest foods on the planet. They represent some of the less impactful on the natural environment.9 Increased consumption of fish, with its diverse and valuable nutritional attributes, can directly reduce the prevalence of malnutrition and correct imbalanced high calorie and low micronutrient diets.2
An increasingly acidic ocean dramatically impacts the health of many fisheries, impacting fishermen and those who depend on the protein. Reduced catches result in decreased incomes, affect the economic viability of fishing communities worldwide, and impact the livelihood of vulnerable indigenous people in tribal fishing communities.
Fishermen from the Gulf of Maine to the Chesapeake Bay, the Gulf of Mexico, and Patagonia also feel the impact. Local catches have been reduced as many fish species die off and others migrate away from reefs and coastal areas to less harmful waters.10
PRESERVING THE OCEANS OF THE WORLD FOR FUTURE GENERATIONS
Kathryn Hautanen, Program Manager, Ocean and Climate Innovation Accelerator (OCIA), said, “We’re working with over a dozen teams at WHOI facing design challenges and offering funding to support research, furnishing the latest advanced hardware, and access to ADI’s technical expertise. The consortium is helping WHOI and its scientists and engineers accelerate their work and develop innovative new solutions to better understand the impacts of climate change on the oceans.”
TECHNOLOGY PLAY: ACCURATE, EXTENSIVE, LOWER COST MEASUREMENT NEEDED
One OCIA project, with an incubation grant of $100k to marine chemists Dr. Z. Aleck Wang and Jennie Rheuban and physical oceanographer Glen Gawarkiewicz, aims to develop a prototype, low cost in situ sensor system for high frequency, customizable measurements of seawater pH. The sensor development will target deployment on fishing vessels or other opportunistic platforms for high resolution measurements throughout the water column in the coastal ocean. “We plan to give the instruments to the fishermen, have them strap it onto their gear, and throw it out into the water,” said Jonathan Pfeifer, an MIT-WHOI Joint Program graduate student working on the project. “Ideally, we want to continuously measure pH as the instrument goes down the water column. Once the fishermen bring the device back up, it will offload the data wirelessly to the cloud where all scientists and other fishermen can access it.”
We’re looking to augment the existing data sets with a much higher density of observations in targeted regional areas to provide a broader picture of what’s happening (for ocean acidification),” said Pfeifer. Monitoring ocean acidification efficiently and cost-effectively is critical to tracking the conditions of the ocean and protecting shellfish health. Leveraging fishing vessels already in the region is a cost-effective way to get wide-scale data. The fishermen are key stakeholders in the data.
“Using semiconductors can make devices an order of magnitude smaller, cheaper, and more power efficient. The sensing technologies used in WHOI’s flows are amenable to chip scale manufacturing,” said Hautanen.
ADI, WHOI scientists and engineers, and Pfeifer are collaborating and leveraging ADI technologies proven in different fields to develop the first small, affordable, easy-to-use, automated in situ pH sensor. The tool must be capable of taking continuous measurements at sea and does not require complex and expensive components. The goal is to empower an army of fishermen citizen scientists with a powerful instrument in the battle against ocean acidification, climate change, and food insecurity.
MEASURING OCEAN ACIDIFICATION
WHOI’s challenge was identifying and integrating the most practical technology for generating a beam of light and processing the absorbance data.
The pH sensor measures pH by employing a tiny amount of pH-sensitive dye mixed with seawater. A beam of light is then shined through the fluid mixture to measure the absorbance at two wavelengths. Very high precision measurements for oceanographic pH can be achieved using this method.
PARTNERING TO CREATE A SPECTROMETER
“I spoke with OCIA’s Kathryn Hautanen, who connected me with Guixue Bu, an ADI Staff Engineer,” said Pfeifer. “Guixue reviewed our requirements and the ADI’s ADPD4101 analog front end (AFE) was chosen for its accuracy, real-time sensing, small form factor, ease of use, and low cost. The miniaturized solution includes a complete, highly integrated photometric, multimodal sensor front end that outperforms any of the other prototype spectrometric systems we had developed before, all in a single chip!.”
SPEEDING UP DEVELOPMENT WITH A REFERENCE DESIGN
ADI created a reference platform to enable rapid prototyping of liquid analysis measurements. Without a reference design, most solutions require a highly experienced engineer to develop circuitry, write software, simulate, perform extensive testing, layout, and manufacture the board. The process can often take months.
“If you have a tough electrical problem, it’s not always straightforward how to solve it,” said Pfeifer.“A reference design can give you a quick answer, often within a day of opening that box. Using ADI’s CN0503 optical liquid analysis reference platform, I could just open the box, plug it in, download some reference code, and start making measurements—skipping a lot of development time and experimentation.”
“Analog Devices’ CN0503 evaluation kit was a game-changer for testing the ADPD4101,” Pfeifer said. “It fit our needs perfectly, saved us months of development time, and its performance completely exceeded our expectations. It’s clear that Analog Devices is at the forefront of technology, and I can’t wait to see what else they come up with.”
OCEAN WEATHER FORECASTING AND NEXT STEPS
A prototype of WHOI’s low cost pH sensor is well underway in development. “Cost is expected to run a few thousand dollars, ten times cheaper than all the other estimates we’ve been making for other instruments,” said Pfeifer. “The next step for us is to submit a proposal to a federal agency or private foundation and scale the program up across the waters off the Northeast coast of the United States as a demonstration of capabilities,” said Dr. Z. Aleck Wang, who leads the project at WHOI.
OCIA’s initiative to monitor the ocean is designed to provide data that helps address the decline in fishing yields, the result of climate change and overfishing since the late 19th century. Research is needed to address the threat of ocean acidification and help maintain the marine ecosystem. Exploring new solutions to address ocean acidification and its impact on marine life may help safeguard food security for billions of people across the globe.
1 “The ocean–the world’s greatest ally against climate change.” United Nations.
2 “The State of World Fisheries and Aquaculture, Sustainability in Action.” Food and Agricultural Oranization of the United Nations, 2020.
3 “The State of World Fisheries and Aquaculture, Sustainability in Action.” Food and Agricultural Oranization of the United Nations, 2020.
4 “What Is Carbon Sequestration and How Does it Work?.” University of California, Davis, September 2019.
5 Lauren Morello and Climate Wire. “Ocean Acidification Threatens Global Fisheries.” Scientfic American, December 2010.
6 Michael Slezak. “The Greate Barrier Reef: a catastrophe laid bare.” The Guardian.
7 “The State of Food Security and Nutrition in the World 2021.”Food and Agriculture Organization of the United Nations, 2022.
8 “World Population Prospect.” United Nations, 2017.
9 “The State of World Fisheries and Aquaculture, Towards Blue Transformation.” Food and Agricultural Oranization of the United Nations. 2022.
10 Asuna P. Gilfoyle and Wilow A. Baird. “The Impact of Rishing Ocean Acidificaton Levels on Fish Migration.” Gilfoyle Research.
