A composite image of blooming phytoplankton and swirling currents along the coast of California and western Mexico. (Credit: Norman Kuring / NASA)听
CU Boulder researchers have developed a method that could enable scientists to accurately forecast ocean acidity up to five years in advance. This would enable fisheries and communities that depend on seafood negatively affected by ocean acidification to adapt to changing conditions in real time, improving baby直播app and food security in the next few decades.听
Previous studies have shown the ability to predict ocean acidity a few months out, but this is the first study to prove it is possible to predict variability in ocean acidity multiple years in advance. The new method, described today in , offers potential to forecast the acceleration or slowdown of ocean acidification.听
鈥淲e've taken a climate model and run it like you would have a weather forecast, essentially 鈥� and the model included ocean chemistry, which is extremely novel,鈥� said , lead author of the study, and a doctoral candidate in the Department of Atmospheric and Oceanic Sciences.听
For this study the researchers focused on the California Current System, one of four major coastal upwelling systems in the world, which runs from the tip of Baja California in Mexico all the way up into parts of Canada. The system supports a billion-dollar fisheries industry crucial to the U.S. economy.
Top: Oysters are a popular menu item听and an animal affected by ocean acidification. (Credit: Patricia Alexandre / Pixabay) Bottom: Harvested oysters on a dock in Morro Bay, California. (Credit: Sarah Stierch / Creative Commons)
鈥淗ere, you've got physics, chemistry, and biology all connecting to create extremely profitable fisheries, from crabs all the way up to big fish,鈥� said Brady, who is also a graduate student at the Institute of Arctic and Alpine Research (INSTAAR). 鈥淢aking predictions of future environmental conditions one, two, or even three years out is remarkable, because this is the kind of information that fisheries managers could utilize.鈥澨�
The California Current System is particularly vulnerable to ocean acidification due to the upwelling of naturally acidic waters to the surface.
鈥淭he ocean has been doing us a huge favor,鈥� said study co-author Nicole Lovenduski, associate professor in atmospheric and oceanic sciences and head of the Ocean Biogeochemistry Research Group at INSTAAR.听
The ocean absorbs a large fraction of the excess carbon dioxide in the Earth鈥檚 atmosphere derived from human activity. Unfortunately, as a result of absorbing this extra man-made carbon dioxide 鈥� 24 million tons every single day 鈥� the oceans have become more acidic.听
鈥淥cean acidification is proceeding at a rate 10 times faster today than any time in the last 55 million years,鈥� said Lovenduski. 听
Within decades, scientists are expecting parts of the ocean to become completely corrosive for certain organisms, which means they cannot form or maintain their shells.听
鈥淲e expect people in communities who rely on the ocean ecosystem for fisheries, for tourism and for food security to be affected by ocean acidification,鈥� said Lovenduski.听
This spells trouble for the California Current System, with its naturally corrosive waters. This extra acidification could push its fragile ecosystems over the edge.听
The fortune and frustration of forecasting
People can easily confirm the accuracy of a weather forecast within a few days. The forecast says rain in your city? You can look out the window.听
But it鈥檚 a lot more difficult to get real-time measurements of ocean acidity and figure out if your predictions were correct.听
Top: Pteropod snails, which live in the听California Current System,听are especially sensitive to ocean acidification. This image shows its effects, including ragged, dissolving shell ridges on upper surface, a cloudy shell in lower right quadrant, and severe abrasions. (Credit: NOAA Photo Library / CC) Bottom: In laboratory experiments, this pterapod shell dissolved over the course of 45 days in seawater adjusted to an ocean chemistry projected for the year 2100. (Credit: NOAA Environmental Visualization Laboratory)
But this time, CU Boulder researchers were able to capitalize on historical forecasts from a climate model developed at the National Center for Atmospheric Research. Instead of looking to the future, they generated forecasts of the past using the climate model to see how well their forecast system performed. They found that the climate model forecasts did an excellent job at making predictions of ocean acidity in the real world.
However, these types of climate model forecasts require an enormous amount of computational power, manpower, and time. The potential is there, but the forecasts are not yet ready to be fully operational like weather forecasts.听
And while the study focuses on acidification in one region of the global ocean, it has much larger implications.听
States and smaller regions often do their own forecasts of ocean chemistry on a finer scale, with higher resolution, focused on the coastline where fisheries operate. But while these more local forecasts cannot factor in global climate variables like El Ni帽o, this new global prediction model can.听
This means that this larger model can help inform the boundaries of the smaller models, which will significantly improve their accuracy and extend their forecasts. This would allow fisheries and communities to better plan for where and when to harvest seafood, and to predict potential losses in advance.听
鈥淚n the last decade, people have already found evidence of ocean acidification in the California current,鈥� said Brady. 鈥淚t's here right now, and it's going to be here and ever present in the next couple of decades.鈥澨�
Additional authors on this study include Stephen Yeager, Matthew Long and Keith Lindsay of the National Center for Atmospheric Research.听
