Microsoft Word 221110 6min english controlling the weather docx

6 Minute English
 
©British Broadcasting Corporation 2022 
bbclearningenglish.com 
Page 3 of 5 
Neil 
Unlike cloud-seeding, the next type of weather modification has never been 
tested and is still just a theory. ‘Solar geo-engineering’ aims to reduce global 
warming by reflecting sunlight away from the Earth, back into space. This 
involves putting tiny particles called aerosols into the stratosphere - the band of 
sky twenty kilometres above the surface of the earth, about twice as high as 
airplanes fly. 
 
Sam 
Although it’s never been tested, the method is controversial, as Charmaine 
Cozier discussed with Harvard University professor of engineering, David Keith, 
for BBC World Service’s, The Inquiry: 
 
Charmaine Cozier
How controversial is this area? 
Professor David Keith 
There's lots of controversy around solar geo-engineering - and for good reason. 
People are, I think, sensibly scared that this could provide an 
excuse
that allows 
countries or companies to avoid doing the work that has to be done to cut 
emissions. But in fact, controversy has really 
waxed and waned
over time, so in 
the early work on climate change in the 1960s, and 70s and early 80s, these ideas 
were just part of the way we talked about what might happen about climate 
change. And then, as climate change became more politically central, say in the 
90s and 2000s, there was really a 
taboo.
Neil 
David Keith believes that geo-engineering could provide an 
excuse
for inaction 
on climate change – a reason for countries to explain why they did not take 
action. 
Sam 
He says controversy over the method has 
waxed and waned - 
an idiom 
connected with the cycle of the moon which describes something that increases 
then decreases over time. In the 1960s for example, geo-engineering was 
uncontroversial, but by the 1990s it had become