Trawler [image credit: BBC]
Any deliberate large-scale interference in natural processes must be fraught with risks and difficulties. Nevertheless some scientists think they should seek to impose their will on nature, invoking climate models and CO2-obsessed theories as the excuse.
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Removal of excess carbon dioxide in the atmosphere, in addition to major reductions in ongoing emissions, is required to stave off the most severe consequences of climate change, claims EurekAlert [Talkshop comment – without offering any evidence].
Large-scale ocean iron fertilization is one of several strategies that could help remove carbon dioxide, but new research published this week in Global Change Biology by a Bigelow Laboratory for Ocean Sciences researcher and colleagues shows that it might also negatively affect marine ecosystems in far corners of the ocean.
Using advanced models of ocean biogeochemistry and ecology, the team showed that iron fertilization in the Southern Ocean could exacerbate climate change-driven nutrient shortages and productivity losses in the tropics, potentially hurting the coastal fisheries on which many people rely.
The findings illustrate both the interconnected nature of the ocean and the need for more objective research on the relative advantages and unintended consequences of marine carbon dioxide removal.
“These modeling experiments demonstrate the need to understand not only the implications of marine carbon dioxide removal strategies for carbon cycling, but also the ecological and ‘downstream’ implications, even those decades in the future or thousands of miles away,” said Bigelow Laboratory Senior Research Scientist Ben Twining, one of the study’s co-lead authors.
The ocean is the planet’s largest sink for carbon emissions. Unsurprisingly, then, plans for carbon dioxide removal are increasingly focused on marine-based strategies like iron fertilization.
The basic idea is that adding valuable micronutrients to certain areas of the ocean — like the iron-limited Southern Ocean — will stimulate primary productivity by allowing other nutrients to be more completely consumed, enhancing the amount of carbon dioxide that phytoplankton absorb at the surface and, ultimately, sink to the seafloor when they die.
Advocates for ocean iron fertilization have pointed out that the solution doesn’t require land or freshwater and can be implemented more quickly than other strategies. And past modeling efforts have shown that iron fertilization does indeed reduce atmospheric carbon.
However, early research also showed that fertilization could exacerbate a process known as “nutrient robbing” by hampering the supply of critical nutrients from iron-limited areas to adjacent regions, in turn reducing the amount of marine life and productivity at the tropics.
On top of that, a 2021 report by the U.S. National Academies of Science argued that the current knowledge base around marine carbon dioxide removal approaches like fertilization was insufficient, especially when it came to scientists’ understanding of how fertilization would interact with other climate-change driven changes to ocean processes.
To help fill some of those knowledge gaps, the authors of the current study expanded previous modeling work, incorporating recent research on how phytoplankton use micronutrients like iron and additional considerations for climate change and fisheries impacts.
“One of the new aspects of our work was to layer ocean iron fertilization on top of climate change,” Twining said. “We also connected our results to a fisheries model, as a way to put the predicted changes in productivity into terms that are more meaningful to people.”
Their results showed a five percent decline in the biomass of fish and marine species in the tropics, including economically important coastal areas, due to large-scale iron fertilization. This was on top of a 15 percent decline expected due to climate change as warming temperatures stratify the ocean, depriving the surface of critical nutrients.
“It’s notable how the ‘fingerprint’ of ocean iron fertilization on the levels of nutrients was similar to that expected from climate change,” said co-lead author of the study, Alessandro Tagliabue at the University of Liverpool. “This raises significant hurdles to the detection and monitoring of any negative impacts of fertilization.”
Full article here.
Tallbloke's Talkshop 
Is there a competition to see who can come up with the most lame brained idea for messing up the environment? Or are they just following the diktats of the Club of Rome and the UN to reduce the earth’s population?
Maintaining a general air of synthetic crisis no doubt helps with research funding, and feeds the climate propaganda machine.
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there seems to be a WP glitch with the usernames at the moment. Corrected now.Known problem — https://wordpress.org/support/topic/author-name-for-posts-showing-as-1/
I rarely bother to read of any of such claims now I understand the scale of natural climate control system versus any perturbation and the simple fact these studies are nit a deterministic study of a definite theory tested by independent observation, what we used to call “science”, rather they are made up ona model without serious observational study under controlled conditions that are primarily designed to attract a a grant so support consensual thought and consider such complex multivariate systems their predictions can have no merit, and are usually too vague to ever be proven either way. They do satisfy the criteria of keeping a pointless and unadeqaute person employed as an academic at taxpayers expense doing meaningless work, a version of the back to work schemes that keep pointless people off the dole queue at society’s expense – like NHS diversity managers and Local Council “Active TRavel” managers. Save your life for real things. Back to reality?
Featured article: The models did show that iron fertilization could remove up to 45 gigatonnes of carbon dioxide from the ocean surface between 2005 and 2100. But, while removing half a gigatonne a year is not insignificant, the authors stress it’s very limited when compared to the current rate of carbon emissions — and the reductions required to meet climate targets.
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So a lot of effort and expense for negligible results at the global scale?
Reblogged this on Climate Collections.
https://earthobservatory.nasa.gov/features/Martin
“In July 1988, during at a lecture at the Woods Hole Oceanographic Institution, oceanographer John Martin stood up and said in his best Dr. Strangelove accent, “Give me a half tanker of iron, and I will give you an ice age.”
I’m less worried about an ice age and a lot more worried about potential of reduction of atmospheric CO2 and the impacts on the terrestrial biosphere.
[reply] interesting link
The iron fertilization theory is based on the faulty premise that CO2 is a driver of atmospheric processes instead of being an effect of other processes.