Printed September 24, 2025
By Alana M. Carlson, Marine Geoengineering Campaigner on the Heart for Worldwide Environmental Legislation
That is the third evaluation in a multipart collection exposing the threats and dangers related to geoengineering and why these applied sciences should not be thought-about efficient local weather motion.
Because the local weather disaster escalates, so does the seek for options. Geoengineering — large-scale technological intervention in Earth’s local weather system — is more and more coming into mainstream discourse. However behind the undeliverable guarantees of cooling the planet and capturing carbon lies a harmful actuality: geoengineering might devastate biodiversity and disrupt ecosystems, whereas sidelining actual local weather motion.
At a time when Earth’s biodiversity is beneath immense strain from local weather change, air pollution, and habitat destruction, geoengineering dangers accelerating ecosystem collapse and species extinction. If deployed at giant scale, these extremely speculative interventions within the Earth’s ambiance, oceans, and land might basically alter the fragile stability of Earth’s important methods, severely compromising our capacity to guard the biosphere and restore it to a state that higher regulates local weather situations and gives important ecosystem capabilities. By creating the phantasm of a “plan B,” geoengineering additionally dangers delaying essential motion to chop greenhouse gasoline emissions and implement actual options to the local weather disaster.
For these causes, the UN Conference on Organic Variety (CBD) had the foresight to take a collection of precautionary selections referring to geoengineering, together with setting up a de facto moratorium on deployment, with strict standards for experiments, in 2010. The moratorium has been reaffirmed repeatedly — together with most just lately on the United Nations’ biodiversity convention in October 2024 (CBD COP16) — in response to concern concerning the development in uncontrolled experiments.
The Biodiversity Impacts of Geoengineering Strategies
Biodiversity describes the richness of life that makes up ecosystems. Strong biodiversity is crucial for wholesome ecosystems and our well-being. It underpins vital capabilities, like pollination and local weather regulation, and permits Earth to stay within the comparatively secure local weather situations which have allowed life to thrive and flourish. Nevertheless, geoengineering experiments pose grave threats to this already fragile stability.
Central to understanding geoengineering — and its potential for critically undermining biodiversity and human rights — is the size at which it’s proposed, each geographical and temporal, with a purpose to have a climatically related influence. Photo voltaic geoengineering deployment is theorized and modelled on tons of of years of steady deployment and as a planetary-scale intervention, whereas sure ocean carbon dioxide elimination (CDR) methods are theorized as using 10-20 p.c of the ocean’s floor and working for many years, if not centuries, and a few land-based methods are estimated to make the most of twice the world’s at present cultivated land.
Under, we discover the dangers that completely different geoengineering methods pose to biodiversity.
Environment-Primarily based Geoengineering Might Set off World Ecological Disruptions
Photo voltaic radiation modification (SRM) applied sciences are extremely speculative methods that search to artificially cool the planet with out addressing the drivers of the local weather disaster. Deployment of those applied sciences would introduce novel dangers and harm to folks and the planet. Amongst these dangers is the opportunity of termination shock (an abrupt rise in world temperatures on account of discontinued SRM), which signifies that if we have been to start out utilizing these methods, we might by no means cease with out risking catastrophic hurt.
Stratospheric aerosol injection (SAI) and marine cloud brightening (MCB) are proposed SRM methods that would dim the quantity of solar that reaches Earth. If this occurred, it might seemingly have destructive impacts on plant species throughout the planet, leading to elevated meals insecurity. Moreover, these applied sciences would seemingly result in uneven temperature modifications, corresponding to extra cooling within the tropics and warming within the poles. Such modifications would trigger temperature stress — very similar to that noticed with local weather change — that species can be unable to adapt to, resulting in destructive results throughout ecosystems globally.
Additional harms from SAI embody modifications in precipitation and harm to the ozone layer. SAI would decelerate the worldwide water cycle, seemingly inflicting as much as a 2 p.c lower in imply precipitation, which might undermine meals and water safety in all places. Some types of SAI would seemingly weaken our ozone layer, thereby permitting extra dangerous UV rays to achieve Earth and species that will be unable to shortly adapt to the elevated radiation.
Marine microbubbles — an SRM method that proposes utilizing synthetic substances to extend the longevity of bubbles left within the wake of ships — might trigger localized mild dimming, and like SAI and MCB, termination shock if stopped abruptly after a interval of steady large-scale deployment.
As photo voltaic geoengineering doesn’t handle the basis causes of local weather change, and on the similar time introduces the chance of mitigation deterrence, it’s seemingly that the preexisting disaster of ocean acidification can be exacerbated, leading to direct hurt to the bottom of marine meals webs and communities that depend on marine species for his or her livelihoods.
Marine Carbon Dioxide Elimination Threatens Ocean Ecosystems
Marine carbon dioxide removals goal to pressure the ocean to sequester much more carbon than it already does. If deployed, these unproven, energy-intensive approaches would introduce immense novel dangers to our already strained marine ecosystems and certain severely hurt biodiversity to the detriment of marine capabilities and human well-being.
Ocean alkalinity enhancement (OAE) applied sciences suggest growing the oceans’ uptake of CO2 by making marine waters extra alkaline — both via the introduction of processed alkaline minerals or by processing seawater electrochemically to take away acid from it. Mineral OAE comes with a excessive mining price, comparable to at present’s world iron ore business, which might degrade freshwater and terrestrial ecosystems. Mineral OAE proposals pose direct hurt to marine life via the introduction of extremely caustic alkaline supplies or extremely alkalinized water that may burn marine species. OAE might trigger short-term shock results related to the introduction of excessive alkalinity, and should trigger additional, not but understood long-term impacts on biodiversity as properly. Electrochemical OAE would contain processing huge volumes of seawater, harming marine life within the course of, and creating huge portions of acid waste that require therapy and disposal. It’s a extremely energy-intensive course of that dangers displacing renewable power, higher directed towards decarbonizing power methods and offering power entry.
Ocean fertilization (introducing micro- and macronutrients to the ocean to encourage algae development) dangers disrupting the connectivity of marine ecosystems. Such disruptions would seemingly impede the flexibility of migratory species to maneuver as wanted and be a barrier to many species’ copy. These methods threat creating poisonous algal blooms that poison marine species. Oxygen depletion occasions that will result in the suffocation of species may happen. Ocean iron fertilization has already been proven to be ineffective, and deployment is prohibited internationally.
Artification upwelling (pumping cool, nutrient-rich deep-sea waters to the floor via hundreds of pipes) could also be performed in tandem with ocean fertilization and dangers bringing saved carbon up from the deep ocean, which can intensify ocean acidification. Moreover, like MCB and marine microbubble enhancement, seaweed cultivation applied sciences are more likely to trigger localized mild dimming, which might disrupt the idea of meals webs.
Seaweed cultivation can also be proposed together with biomass sinking, the place bales of plant matter can be dumped on the backside of the ocean to extend marine carbon storage. Along with seaweed, wooden, and crop residues from land are additionally proposed for this goal. These methods disregard the truth that deep-sea life is delicate, largely unknown, and gives many important ecosystem capabilities, together with oxygen and nutrient biking within the oceans. They threat bodily harms brought on by depositing bales of biomass on the ocean flooring, in addition to from bottom-up acidification, which might happen on account of the biomass’s inevitable decay. Such harms would result in destructive impacts throughout meals webs, hurt marine biodiversity, and communities reliant on marine ecosystems for his or her livelihoods.
Land-Primarily based Geoengineering Would Disrupt Ecosystems on a Huge Scale
Enhanced weathering (EW) is OAE’s terrestrial cousin. It might see floor alkaline supplies unfold over farmlands and fields to artificially improve CO2 uptake. Like OAE, to do at scale EW would require an unlimited quantity of mining comparable to at present’s iron ore business, and would result in all of mining’s related harms. This system comes with uncertainties concerning the ecological toxicity impacts of spreading crushed, uncharacterized, or poorly characterised supplies over land-based ecosystems and agricultural lands.
Biochar (storing carbon as charcoal unfold over land) and bioenergy with carbon seize storage (BECCS) would include excessive ecological prices. To implement these applied sciences at scale would require rising biomass plantations on greater than twice the land at present cultivated. These plantations would trigger a large lack of biodiversity as a result of habitat and meals loss, in addition to elevated publicity to and decreased resilience to ailments. Moreover, fertilizer manufacturing and use must be scaled up, exacerbating the harms related to it.
Biochar would additionally introduce distinctive air pollution dangers. Along with utilizing biomass for biochar, so-called feedstocks for it could actually embody crop and wooden residues, manure, tires, plastics, municipal waste, and sewage — all of which include distinctive toxicity dangers. Toxins taken up by crops grown in biochar-amended soils might lead, over time, to the buildup of lethal arsenic, cadmium, lead, and mercury in animals and people. People and animals would even be uncovered to those toxins as airborne pollution.
Direct air seize (DAC) is a expertise that seeks to soak up CO2 from the air via solvents or sorbents that carry not but understood dangers for biodiversity from their manufacturing. The set up of DAC crops would exacerbate ecosystem fragmentation and trigger immense water stress wherever deployed. Capturing as much as 1 p.c of annual greenhouse gasoline emissions would require as a lot water as 144 nations eat domestically yearly. DAC additionally introduces novel dangers of CO2 leaks across the crops, which can result in suffocation occasions or fast water acidification. The expertise can also be extremely energy-intensive and carries the identical dangers as electrochemical OAE on this respect. Moreover, captured CO₂ from DAC can also be utilized in enhanced oil restoration (EOR), which claims to retailer CO₂ whereas extracting extra oil. Thus, DAC is used to falsely label EOR as “low carbon” regardless of the elevated emissions on the injection website and its continued help of additional fossil gasoline manufacturing.
A Unhealthy Wager for the Planet, a Unhealthy Wager for Folks
The potential direct and oblique harms to biodiversity and ecosystem capabilities from geoengineering imply these applied sciences pose important, unprecedented, never-before-seen dangers to a variety of human rights. The UN Human Rights Council’s Advisory Committee has warned that the deployment of geoengineering applied sciences has the potential to violate the human rights of “thousands and thousands and maybe billions of individuals,” with the best influence on Indigenous Peoples, rural communities, and fisherfolk. Among the many many human rights that will be undermined as a result of hurt to biodiversity are the rights to life, the rights of future generations, and the proper to tradition.
Untestable besides via experimentation at a big scale, the true extent of social, financial, and cultural harms of geoengineering would seemingly turn into obvious solely as soon as deployed. The harms to biodiversity and human rights might create “sacrifice zones” that additional entrench the fossil financial system and its harms, in addition to different preexisting inequalities on the expense of these most weak to the local weather disaster.
Precaution Over Hypothesis: What Ought to Policymakers Do?
The worldwide response to geoengineering should be guided by precaution, environmental justice, and human rights. Geoengineering is neither insurance coverage to “purchase time” nor any type of complement to mitigation. As an alternative of entertaining harmful, extremely speculative applied sciences, policymakers should stop the normalization of geoengineering in local weather coverage and prioritize actual local weather options that defend and restore biodiversity, together with a full, honest, funded, and quick phaseout of fossil fuels.
To stop the dangers of geoengineering and defend folks and the planet, governments ought to:
Implement and implement the CBD’s de facto moratorium on geoengineering domestically and throughout worldwide fora
Help the event of sturdy precautionary regulatory controls beneath the London Conference/London Protocol to dam dangerous ocean-based geoengineering
Ban all outside geoengineering experiments, stopping any fast hurt and deterring expertise growth
Work towards a Photo voltaic Geoengineering Non-Use Settlement to forestall harmful planetary-scale manipulations of daylight
Cease public help and funding for geoengineering applied sciences and deny patents
Reject geoengineering in local weather insurance policies and carbon market mechanisms, stopping its use as a loophole to proceed emitting greenhouse gases
Defend biodiversity and ecosystem integrity by avoiding dangerous interventions, minimizing unavoidable impacts, and restoring broken ecosystems
Uphold the inherent and collective rights of Indigenous Peoples and the rights of frontline communities, making certain their lands will not be was sacrifice zones for speculative geoengineering tasks
Urgently prioritize actual options to the local weather disaster via a quick, honest, funded, and full phaseout of fossil fuels
The Future We Select
The local weather disaster calls for pressing motion — however not reckless interventions that jeopardize biodiversity and human rights. Policymakers should resist the phantasm of geoengineering and as an alternative decide to confirmed rights-based options. A world free from fossil fuels, rooted in justice and ecological integrity, is feasible — however provided that we reject false options and embrace actual local weather motion now.
Picture Credit score: Flickr-Joseph-King2013 TAMU Utilized Biodiversity Sciences Amazon Subject Faculty on the Tambopata River within the Peruvian Amazon
