Cool Earth today
Harvard scientists will try to replicate the effects of volcanic eruptions on the climate with the help of the world’s first experiment in the field of solar geo-engineering.
In the course of a project called “Controlled Stratospheric Perturbation Experiment (SCoPEx)” scientists will spray calcium carbonate particles high above the ground in order to reflect sunlight.
This will be the first time when a controversial concept will be used in practice. The existing approach to the solution of the problem comes from computer modeling, as well as observation of the natural effects of volcanoes that create haze from sulfate particles, which effectively cools the Earth. For example, the 1991 Pinatubo eruption in the Philippines reduced average global temperature by about 0.6 degrees Celsius over the next 15 months.
The project will be led by a Harvard team led by scientists Frank Coych and David Keith. They have been working on the SCoPEx project for several years and in a recent interview with Nature mentioned that they will begin the start phase of the experiment in the first half of 2019.
“Computer modeling and laboratory work give us some very useful information about solar geo-engineering. But as in all other aspects of science computer models are ultimately based on observations of the real environment “, – the scientists commented.
Critics about the cooling of the Earth
Although geo-engineering has long been a controversial science, recently the Intergovernmental Panel on Climate Change (IPCC) at the UN has confirmed its potential as Plan B. One of the main reasons for distrust of this field of research was the lack of global experiments. That is why the success of SCoPEx, the first project of such tests, will be closely monitored.
The method used by the team of scientists is that the stratosphere will be filled with calcium carbonate. The experiment will take place in a small area 20 kilometers above the southwest of the United States. Researchers will release a cylinder that injects a small amount of calcium carbonate, about 100 grams at a time and then descends to the ground. Then this design goes back to record the results of the experiment.
According to the article “Nature”, Koich and Keith intend to start the project in the spring of 2019. The SCoPEx team hopes that their results will help build a more informed public and academic debate on solar geo-engineering. Critics argue, however, that any attention drawn by this emerging science diverts from real global efforts to reduce greenhouse gas emissions. According to them, solar geo-engineering at most only masks the consequences of such pollution, rather than reduces it. Also, the main concern of scientists is a potential “stop shock”. In case the project ever stops, it is very difficult to anticipate side effects.