Next month, researchers in the U.K. will start to pump water nearly a kilometer up into the atmosphere, by way of a suspended hose.
The experiment is the first major test of a piping system that could one day spew sulfate particles into the stratosphere at an altitude of 20 kilometers, supported by a stadium-size hydrogen balloon. The goal is geoengineering, or the “deliberate, large-scale manipulation of the planetary environment” in the words of the Royal Society of London, which provides scientific advice to policymakers. In this case, researchers are attempting to re-create the effects of volcanic eruptions to artificially cool Earth.
The $30,000 test, part of a project called Stratospheric Particle Injection for Climate Engineering (SPICE), is inspired by the 1991 eruption of Mount Pinatubo in the Philippines. That volcano spewed 20 million tons of sulfate particles into the atmosphere, cooling Earth by 0.5 degree Celsius for 18 months. If the British feasibility tests are successful, the balloon-and-hose contraption could be used to inject additional particles into the stratosphere, thereby reflecting more of the sun’s energy back into space, and hopefully curbing some of the effects of global warming.
“This is one of the first times that people have taken geoengineering out of the lab and into the field,” lead scientist Matthew Watson said Tuesday during a press conference in London. “We are still decades away—and I do mean decades—from doing real geoengineering.” Watson said his team still needs to determine which substances would work best at reflecting light, how much is needed to have an effect, and the possible unintended consequences of injecting the particles into the atmosphere, such as acid rain, ozone depletion or weather pattern disruption.