SCoPEx plans to launch a high-altitude balloon from the Esrange Space Station near the Arctic town of Kiruna in Sweden this June.

Harvard University’s solar geoengineering project dubbed as Stratospheric Controlled Perturbation Experiment (SCoPEx) plans to launch a high-altitude balloon from the Esrange Space Station near the Arctic town of Kiruna in Sweden this June.

This will test the ability of the balloon to carry a gondola with 600 kg scientific equipment about 12 miles (20 km) high that will release solar radiation-reflecting particles in the stratosphere.

The SCoPEx project aims to dim the sunlight by reflecting the radiation to space in an effort to help cool the planet. In a previous report by Science Times, Bill Gates and other private donors have expressed their intention of supporting this program to block sunlight from reaching Earth’s surface.

However, reported that the planned test flight of the high-altitude balloon in the summer has been canceled by the US and European scientists due to growing concerns about the possible harmful effects of the controversial solar geoengineering project on the ozone layer and ecosystem.

Controversial Balloon Test Flight Rescheduled to 2022

The SCoPEx project that Harvard scientists hope to become a method to fight global warming mimics the effect of volcanic eruptions in cooling the planet.

But solar engineering has since raised many concerns both from scientists and environmentalists who said that this method is risky and dangerous for the whole planet.

In a statement last March 31, state-owned Swedish Space Corporation (SSC), which operates Esrange said that the scientific community is divided on the benefits of solar geoengineering. Following discussion with experts, the SSC has decided not to continue the controversial high-altitude balloon test flight in June.

Moreover, Harvard’s special committee who studies the societal and ethical aspects of the project also called for the cancellation of the test flight to review the implications it will have on Sweden’s indigenous Sami people and generally in Sweden.

They recommended that societal engagement should take place before the SCoPEx test flight will be conducted in the country. Instead this summer, the test flight is likely to happen in 2022.

Solar Geoengineering Pros and Cons

Solar geoengineering could be done by adding sulfur dioxide to the stratosphere, spraying seawater into the air to increase the concentration of droplets in clouds, and spray bismuth tri-iodide high in the atmosphere.

Although it might bright benefits to the Earth it also has its dark side. Here are some of the pros and cons of solar geoengineering according to New Scientist:


  • Could offset global warming
  • Affordable and feasible
  • Adding sulfur dioxide to the stratosphere is similar to the effect of volcanic eruptions on the atmosphere
  • spraying seawater to clouds will not need toxic chemicals


  • Most solar geoengineering methods reduce rainfall
  • Could alter regional climates with disastrous effects
  • Will make the sky whiter
  • No real-world test has been done yet in injecting seawater into clouds so it might not work
  • Carbon dioxide might continue to increase if spraying of seawater and injecting sulfur dioxide is stopped
Originally published at Science Times