Over the past 6 or 8 months the idea of ocean fertilization has been raised many times as a possible scenario to help end – or at least provide assistance to the end – of global warming. However according to a new study conducted by researchers at Stanford and Oregon State Universities such a scheme would not be a major help to the reduction of carbon dioxide in the atmosphere.
Ocean fertilization for the uninitiated is simple; in a conducive area of the ocean, dump large amounts of iron (one of several minerals, but the predominant one) to create an algal bloom. Such blooms are theorized to increase the amount of carbon dioxide the ocean breathes in.
However, according to the new study, the process by which the carbon is directed to the deeper ocean – known by scientists as the “Biological Pump,” does not work effectively during the summer months where a normal bloom occurs.
The theory was put to the test by monitoring the amount of algae in the surface waters of the planet, and comparing that with how much carbon was actually sinking to the bottom. The results showed a clear season pattern in both aspects. But the relationship between the two was what surprised the researchers; less carbon was transported to the bottom during a summertime bloom, than compared to the rest of the year.
This was a new analysis, and thus provided results never before seen before. But it also required the researchers, lead by Dr. Michael Lutz, now at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science, to design new mathematical algorithms.
“By jumping a mathematical hurdle we found a new globally synchronous signal,” said Dr. Lutz.
That aside, it was the results that were the biggest hurdle for people to accept. “This discovery is very surprising”, said lead author Lutz. “If, during natural plankton blooms, less carbon actually sinks to deep water than during the rest of the year, then it suggests that the Biological Pump leaks.”
“More material is recycled in shallow water and less sinks to depth, which makes sense if you consider how this ecosystem has evolved in a way to minimize loss”, said Lutz. “Ocean fertilization schemes, which resemble an artificial summer, may not remove as much carbon dioxide from the atmosphere as has been suggested because they ignore the natural processes revealed by this research.”
So far, all of the carbon sequestration attempts have not produced a marked increase in carbon storage. According to Dr. Lutz, this is not surprising, and is presumably the case no matter the duration or location.
“The limited duration of previous ocean fertilization experiments may not be why carbon sequestration wasn’t found during those artificial blooms. This apparent puzzle could actually reflect how marine ecosystems naturally handle blooms and agrees with our findings. A bloom is like ringing the marine ecosystem dinner bell. The microbial and food web dinner guests appear and consume most of the fresh algal food.”
“Our study highlights the need to understand natural ecosystem processes, especially in a world where change is occurring so rapidly,” concluded Dr. Lutz.
University of Miami Rosenstiel School of Marine & Atmospheric Science via ENN – Ocean Fertilization ‘Fix’ For Global Warming Discredited By New Research
Image Courtesy of Mr. Delgoff