Scientists have a revolutionary to save Earth from global warming. Geo- from Harvard University believe that spraying "sun-dimming" high above the Earth could slow down global warming. They say this would be " inexpensive," costing about $2.25 a year over 15 years. The is called stratospheric injection (SAI). It is still yet to be proven. It would involve using hoses or high-powered cannons to spray chemicals into the . This would be a reflective against sunlight.
The scientists admitted that their idea is in the planning stages. They said: "We make no about the desirability of SAI. We show that a hypothetical deployment , while both highly uncertain and ambitious, would indeed be technically ." Not all scientists think the idea is a one. Some think it is in the sky. They say 100 specially-designed would need to make 4,000 missions a year, crossing most of the globe's . Over 100 governments would need to agree to this. There are concerns it could increase and extreme weather.