As the Arctic warms at four times the global average, long-time glaciologist John Moore has witnessed many of his former research sites vanish. The ice that once provided stable ground for scientific inquiry has melted, prompting urgent efforts to slow or reverse the accelerating climate crisis in the region. Moore, along with the University of the Arctic, has helped identify 61 potential interventions aimed at protecting the Arctic. These include some radical concepts, many of which will be examined at a Cambridge University conference, where scientists and engineers hope to narrow the list to around ten viable options.
The central theme of this initiative is geoengineering, a field that explores large-scale technological solutions to alter the Earth’s climate. Some of the proposals now on the table include sunlight reflection methods (SRM), marine-cloud brightening (MCB), building vast space mirrors, and stabilizing glaciers using underwater curtains. While these ideas once seemed futuristic, they’re increasingly considered essential tools for climate intervention.
Dr. Shaun Fitzgerald, director of Cambridge’s Centre for Climate Repair, supports evaluating these ideas rigorously. He emphasizes that progress in traditional emissions reduction has been too slow and believes it’s vital to explore alternatives. His stance reflects a growing sentiment among researchers: while none of these approaches will solve all climate problems, ignoring them could prove more dangerous than exploring them.
Still, geoengineering is highly controversial. Critics raise serious ethical and legal concerns, especially when local or Indigenous communities are not consulted. For example, the Saami Council joined other groups in opposing a Harvard-led project involving stratospheric aerosol injection (SAI), a method that mimics volcanic eruptions by releasing particles into the upper atmosphere to reflect sunlight. The Saami called the plan a “real moral hazard,” highlighting concerns about unintended consequences and lack of accountability.
Fitzgerald insists that debate and transparency are crucial, which is why the Cambridge conference includes discussions on ethics, governance, and public engagement. Not all proposals hold equal promise. Ocean-based solutions, like altering currents, often come with high risk and uncertainty. Some, including attempts to block the Bering Strait, have already been dismissed as unfeasible.
Marine-cloud brightening is seen by some, including Prof. Peter Wadhams, as the most promising method. Unlike SAI, it can be scaled back quickly if negative effects occur. On the other hand, thickening sea ice through artificial refreezing is criticized for requiring excessive energy, limiting its large-scale viability.
Despite pushback—including moves to ban geoengineering in some U.S. states and UK political debates about its legality—UK scientists are moving ahead with small-scale outdoor tests as part of a £50 million program. Supporters argue that continuing this research is critical, given the rapid pace of climate change.
Ultimately, the Arctic’s future may depend on bold, innovative solutions. As Moore and Fitzgerald stress, it is not about certainty, but about carefully exploring what might work before time runs out. In that context, geoengineering remains a controversial yet increasingly central part of the climate debate.