Geoengineering

The historic Paris climate agreement started a mantra from developing countries: “1.5 to stay alive.” It refers to the international aim to keep global warming under 1.5 degrees Celsius (2.8 Fahrenheit) compared with preindustrial times. But the world will likely pass that threshold within a decade, and global warming is showing little sign of slowing. The world is already facing natural disasters of epic proportions as temperatures rise. Heat records are routinely broken. Wildfire seasons are more extreme. Hurricane strength is increasing. Sea level rise is slowly submerging small island nations and coastal areas. The only known method able to quickly arrest this temperature rise is climate engineering. (It’s sometimes called geoengineering, sunlight reduction methods or solar climate intervention.) This is a set of proposed actions to deliberately alter the climate. These actions include mimicking the cooling effects of large volcanic eruptions by putting la...

When soaring temperatures, extreme weather and catastrophic wildfires hit the headlines, people start asking for quick fixes to climate change. The U.S. government just announced the first awards from a US$3.5 billion fund for projects that promise to pull carbon dioxide out of the air. Policymakers are also exploring more invasive types of geoengineering − the deliberate, large-scale manipulation of Earth’s natural systems. The underlying problem has been known for decades: Fossil-fuel vehicles and power plants, deforestation and unsustainable agricultural practices have been putting more carbon dioxide into the atmosphere than the Earth’s systems can naturally remove, and that’s heating up the planet. Geoengineering, theoretically, aims to restore that balance, either by removing excess carbon dioxide from the atmosphere or reflecting solar energy away from Earth. But changing Earth’s complex and interconnected climate system may have unintended...