Geoengineering = Peak Technohopium

Geoengineering is the dream of bending Earth’s climate back under human control. The word itself sounds futuristic, but the idea is not new.

Decades ago, Soviet scientists fantasized about damming the Bering Strait to warm Siberia. American researchers have proposed spraying reflective particles in the sky to dim the sun. Clouds are seeded to produce rain.

Volcanoes like Mount Pinatubo in 1991 offered a real-world glimpse when their eruption dust cooled the planet for two years. That brief taste of “accidental geoengineering” inspired some to wonder how far we could take it. The polar regions, where ice is collapsing and seas are rising, are currently a target of several geoengineering schemes. A new paper by Siegert and more than 40 polar experts finds that not one of the schemes survives scrutiny.

Big Five Schemes Reviewed:

1. Stratospheric Aerosol Injection

Spray sulfur or calcium carbonate high into the sky so sunlight bounces back into space. In theory, this mimics volcanic eruptions and cools the Earth. In practice, it risks ozone depletion, acid rain, disrupted rainfall, worsened ocean acidification, and sudden “termination shock” if injections ever stop. Cost estimates start at billions, governance is nonexistent, and any effect at the poles would be weak due to long dark winters.

2. Sea Curtains (or Sea Walls)

Giant flexible barriers anchored to the seafloor to block warm water from melting ice shelves. A kind of undersea dam. Models say they might help one glacier, but they could reroute warm water elsewhere. Logistics are nightmarish (remote seas, iceberg collisions, billion-dollar vessels). Even a single 80 km curtain could cost $80 billion, likely a gross underestimate. Ecological disruption to fish, plankton, and nutrient flows would be inevitable.

3. Sea Ice Management

Two flavors: scatter reflective glass beads across Arctic ice, or pump seawater onto ice so it thickens. The glass beads dissolve, darken the ice, and threaten plankton. The pumps would require tens of millions of machines, billions of dollars yearly, and permanent human occupation of the high Arctic. Even if it worked, models show thickened sea ice barely dents global warming.

4. Basal Water Removal

Drill into the base of glaciers, pump out the lubricating water, and slow their flow to the sea. A single borehole in Antarctica cost $13 million; scaling this would multiply costs by thousands. The subglacial plumbing is too complex and shifting for such interventions to matter. Risks include contaminating pristine ecosystems with black carbon and microbes. Effectiveness: negligible.

5. Ocean Fertilization

Dump iron into the Southern Ocean to trigger plankton blooms that suck up CO₂. Tried in the 2000s, halted by 2011. The blooms proved unpredictable, ecological effects unknown, and the CO₂ drawdown small. Under UN law, it already counts as marine pollution. Reviving it now would be more about political theatre than science.

The Lessons

All five schemes fail on the same grounds: too costly, too dangerous, too uncertain, too late.

More troubling, they would act as a political distraction. A shiny techno-fix gives governments and fossil fuel lobbies cover to delay the only cure: cutting emissions fast and deep.

This is the essence of technohopium. We haven't and won't make the hard changes until they are forced upon us by the laws of physics.

So what does this mean for us? The prognosis is sobering. If humanity places its chips on geoengineering, we are betting on illusions. We are gambling our future on fragile machines in impossible places, while the clock runs out on carbon reduction.

The lesson is simple: There is no shortcut.