Dim the Sun to limit global warming, say scientists
20 Questions | Spelling | Dictation
Scientists have a revolutionary idea to save Earth from global warming. Geo-engineers from Harvard University believe that spraying "sun-dimming" chemicals high above the Earth could slow down global warming. They say this would be "remarkably inexpensive," costing about $2.25 billion a year over 15 years. The technique is called stratospheric aerosol injection (SAI). It is still yet to be proven. It would involve using huge hoses or high-powered cannons to spray chemicals into the stratosphere. This would be a reflective barrier against sunlight.
The scientists admitted that their idea is still in the planning stages. They said: "We make no judgment about the desirability of SAI. We simply show that a hypothetical deployment program, while both highly uncertain and ambitious, would indeed be technically possible." Not all scientists think the idea is a good one. Some think it is pie in the sky. They say 100 specially-designed planes would need to make 4,000 missions a year, crossing most of the globe's airspace. Over 100 governments would need to agree to this. There are concerns it could increase droughts and extreme weather.
Try other levels. The listening is a little longer, with more vocabulary.
This page has all the levels, listening and reading for this lesson.
← Back to the sun dimming lesson.