It was a Nobel prize-winning Swedish chemist by the name of Svante Arrhenius (1859-1927) was who first discovered the greenhouse effect. And it didn't take him long to conclude that burning coal (oil was just coming into widespread use as a fuel in the late 19th century) would cause a surprisingly strong increase in that effect. In other words, the earth would heat up.
Unfortunately, as we know, Arrhenius's theory was incorrect.
Never mind, let's plough on anyway.
Thousands of scientists from Arrhenius onwards could all be wrong and the world’s climate will not become substantially warmer. Suppose that's what happens—yet the government introduces measures to avert the catastrophe anyway. Would that be such a bad thing?
Oh look—it's the precautionary principle rolled out again! But the principle is here distorted because there are substantial costs involved in trying to avert this possible problem.
Because we know what measures the government wants to introduce and they will seriously constrict our freedom; further, they will make us all poorer—and poverty causes death. Especially in the Developing World.
Perhaps I am being unjust; after all, it may be that the author, Valdemar, feels that the deaths of millions of people is a price worth paying—although I doubt that Valdemar anticipates being one of those who are killed.
But if you do think that millions of deaths is a bad thing then "the government [introducing] measures to avert the catastrophe" which doesn't actually exist is probably not something that you'd support.
So the answer to Valdemar's question is, "yes, it would be a bad thing".
The rest of the piece is a sort of self-indulgent hate-piece about drivers: apparently driving is the root of all evil.
Did I hear some old reactionary ask about evidence-based policies? Well, I appeal to common experience. I can’t present a UN-sponsored scientific report to support my viewpoint, oddly enough. I just think that our car-based society is very effective at suppressing what has long been considered civilized behaviour. And I think we’ve lost something important; something nebulous, and certainly something that’s hard to quantify, but something real and good, nonetheless.
Or, to sum up, here's the shorter Valdemar:
I don't know what it is that we've lost, I have no evidence that we've lost it and I have no data on what might have caused us to possibly lose this thing that I can't define. Ergo driving is definitely evil.