Scientists warn polar geoengineering proposals are dangerous, unlikely to work

Dozens of polar scientists have concluded that a range of proposed geoengineering interventions in the Arctic and Antarctic are dangerous, unlikely to be feasible at scale and could divert attention from the established need to cut greenhouse-gas emissions.

In a review published in the journal Frontiers in Science, more than 40 researchers assessed five widely discussed polar geoengineering ideas — including artificially thickening sea ice, injecting reflective particles into the atmosphere and installing barriers to block warm water from reaching vulnerable glaciers — and found each failed to meet basic criteria for feasibility and acceptable environmental risk. "These approaches are dealing with the symptoms of climate change rather than the causes," said lead author Martin Siegert, a professor of geosciences at the University of Exeter.

The review highlights both local and global hazards. One high-profile concept — spraying tiny reflective aerosols into the stratosphere to cool the planet — could alter weather patterns and raise questions about who would have authority to deploy such measures, the scientists said. Online conspiracy theories that claim ordinary aircraft contrails are evidence of secret geoengineering operations remain unfounded, but many legitimate researchers stress the potential for far-reaching knock-on effects from deliberate atmospheric intervention.

Concerns about governance are acute in polar regions, where decision-making is complex and several nations have competing interests. "If a country were to deploy geoengineering against the wishes of others, it could increase geopolitical tensions in polar regions," said Dr. Valérie Masson-Delmotte, a senior scientist at Université Paris‑Saclay in France, who was cited by the authors.

Practical and economic obstacles also weighed heavily in the assessment. A frequently discussed sea-ice thickening proposal would pump seawater over the surface of Arctic ice in winter to build up a thicker layer ahead of summer melt. The review notes that covering 10% of the Arctic with such systems could require roughly 10 million seawater pumps, a scale likely to be prohibitively costly and logistically unworkable.

Another idea aimed at protecting Thwaites Glacier in West Antarctica — building an underwater barrier to block warm water from undermining the ice — is described by the authors as technically demanding and unlikely to perform as intended at the scale needed to save large glaciers.

Supporters of some geoengineering research say the techniques should be explored as possible supplements to emissions reductions rather than replacements. Dr. Shaun Fitzgerald, director of the University of Cambridge's Centre for Climate Repair, acknowledged the review raised "very valid concerns" but argued further study could help society make more informed decisions about risks versus potential benefits. He said emissions reductions must remain the priority.

The debate over research funding is already under way. A UK government-backed agency recently announced nearly £60 million to support geoengineering-related studies, while the government has said it has no plans to deploy such technologies. The authors of the Frontiers review nevertheless argued that many proposed polar interventions are so unrealistic that resources would be better spent on decarbonisation and on improving basic polar science and observation.

The scientists concluded that, given the current state of knowledge, polar geoengineering carries a high risk of causing "severe environmental damage" and of creating a misleading narrative that technical fixes could substitute for steep reductions in fossil-fuel emissions. They urged governments and funding bodies to prioritise policies and research that directly reduce emissions and improve understanding of polar systems rather than pursue interventions that remain speculative, costly and potentially harmful.