Scientists have come out with a new way to reduce global warming, but this could entail consequences that we do not know. What would happen is that the atmosphere would be shaded from the sun and this would cool the earth, thus compensating for global warming. It is a risky plan.
The concept called solar geoengineering, implies that tiny particles would be injected in the atmosphere. These then would act as a sun shield reflecting sunlight back in space and cooling the planet.
Of course, scientists say that the scheme is not as crazy at it sounds as Nature does it all the time. When volcanoes erupt they spew particles in the atmosphere that do exactly what scientists propose. On a smaller scale the same would happen, with a fleet of aircraft spraying 250,000 metric tonnes of sulfur dioxide into the lower stratosphere. The particles would change how much sunlight is reflected back to space, with less reflection thus a cooling of the planet. Only one percent of sunlight reflected back into space could provide enough cooling to balance the effects of the warming caused by carbon emissions.
Naturally the project would have to be an international effort and would cost about 1 to 10 billion dollars per year. It sounds a lot but could be well worth the effort. After all the United States spends well over 670 billions dollars per year on the military alone.
It is a risky scheme when one tinkers with Nature and a system that has been in use for billions of years. No one can predict the consequences of rolling the dice. What if things become worse? I think it is best to think of this solution as a last gasp, a Hail Mary pass in case we really have no other choices. The best thing is still to drive down emissions and to have countries cooperate to fight global warming as it is in our interest to do so. We all have a stake in this.