An engineer whose speciality is geoengineering(noun)
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Use "geoengineer" in a sentence
"I may have heard the word "geoengineer" once or twice before, but I knew next to nothing about it, other than the fact that it generally referred to people with outlandish ideas about how to counteract global warming."
""geoengineer" the earth's climate, please remember that many cures have ended up being worse than the disease."
"Some have even proposed sulphur dioxide could used to geoengineer the planet by deliberately injecting millions of tonnes into the atmosphere to combat warming."