Researchers at Harvard University are working on a radical plan to cool the Earth. They propose spraying calcium carbonate dust particles into the stratosphere to cool the planet by reflecting some of the sun’s rays into space. The idea comes from the 1991 eruption of Mount Pinatubo, which injected an estimated 20 million tons of sulfur dioxide into the stratosphere, cooling the Earth to pre-industrial temperatures for 18 months.
Reflecting sunlight context
Following in the footsteps of the 1991 Mount Pinatubo eruption, scientists believe a similar process can be used to cool the Earth artificially. This deliberate and large-scale attempt to influence the Earth’s climate is referred to as geoengineering.
Many in the scientific community have warned against the practice of geoengineering, but as global warming continues, some scientists, policymakers, and even environmentalists are reconsidering its use due to current attempts to curb global warming being inadequate.
The project entails using a high-altitude balloon to take scientific equipment 12 miles into the atmosphere, where about 4.5 pounds of calcium carbonate will be released. Once released, the equipment in the balloon would then measure what happens to the surrounding air. Based on the results and further iterative experiments, the initiative can be scaled for planetary impact.
Spraying dust into the stratosphere is a drastic step that could have far-reaching consequences for the Earth and its inhabitants.
The large-scale impact this type of project could eventually have on Earth’s climate has caused some observers to say the project has crossed the moral line of scientific experimentation. Others argue that humanity has already been participating in geoengineering, specifically through the massive amounts of carbon emissions that world populations have pumped into the atmosphere since the first industrial revolution.
The scientific community and environmental groups are paying extensive attention to the project, all of whom worry that this kind of undertaking can distract the world’s attention from reducing greenhouse gas emissions using existing technologies and policies.
Applications for reflecting sunlight
Attempts to reflect sunlight could:
- Succeed in cooling the Earth and reversing climate change, but the project’s long-term consequences are unknown.
- Have severe and unpredictable effects on the Earth’s climate, causing unforeseen complications for life on the planet, such as affecting wind patterns, storm formations and causing novel climate changes.
- Have negative or positive impacts on crop yields globally, especially in farming regions already being adversely affected by climate change
- Lead to protests by environmentalists and the public at large once the dangers of geoengineering become known.
- Halt current attempts to limit greenhouse gas emissions because of the promise that geoengineering could cool the Earth without needing to do so. Geoengineering could stop governments, large companies, and businesses from taking action against climate change.
Questions to comment on
- Does geoengineering hold any positive promise, or is it a risky initiative with too many variables to control?
- If geoengineering succeeds in cooling the Earth, how might it impact the environmental initiatives of large greenhouse emitters, such as countries and large companies?