Global warming and Christian discernment

WorldNetDaily: Global warming and Christian discernment
One of the reasons my children are homeschooled is to avoid the brainwashing they would received in either public schools or even private schools on issues like global warming.
Last week, I learned that one of my children is being taught about the crisis global warming represents in a Christian homeschool cooperative biology class!
It’s bad enough my oldest daughter was forced to endure repeated and required showings of Al Gore’s “An Inconvenient Truth” in an art class in a public college. But now we see this agitprop deceiving even those who should know better.
Nowhere in the Bible does God directly or indirectly warn us of the dangers of carbon dioxide, a natural, non-polluting gas as necessary to life on our planet as oxygen.
Instead, God warns us about a real pollutant in our environment. It’s called sin.
Is there not enough real sin in the world for Christians to combat? Why do believers emulate the world in worrying about a phantom crisis that doesn’t threaten the natural life or eternal fate of even one person on the planet? Where is the ability of these believers to discern truth from fiction?