I kinda see where he's coming from, though. In one sense you could translate the salting of fields "scare" to today's climate change scare, even considering the differences in academic prowess. For instance you could say that -for their time- field salting (I'd never actually heard of this tactic, it's quite interesting if not devious) and its related arguments for/against are similar to today's climate change issue in that Important People (Kings/Energy Companies) are harming the environment and Scientists (scholars of yore/scholars of today) are crying foul.
Beyond that, no I don't think it's at all comparable. One is talking about a few hundred thousand acres of land, vs the whole planet. One is talking about one aspect of said land (fertility) vs. several factors on Earth (weather, tides, coastlines, ecosystems, etc.). I guess this means the major difference between the two is the scope of the problem, but not necessarily the scientific expertise. I'd say both are probably infantile compared to the total picture that will need to be learned in order to fully understand what's really happening.
Meanwhile, I do have an opinion. I think that if anything, climate change is a reality, and that our impact upon it starting with the industrial revolution is indeed speeding up the natural process of it, but I also think that no amount of "slowing down" will actually help. I believe we've already surpassed the point at which it can be reversed... no that's no right. It was never able to be reversed, the planet heats and cools ever X years anyway, it just so happens that by burning 10 bajillion tons of fossil fuels and putting crap in the atmosphere that's not naturally occurring like CFCs and whatnot is pretty much like hitting fast-forward on the planet's normal cycle. We're sure to be destined for another ice age, but instead of it happening say, 5 or 10 thousand years from now, it'll probably be next week.
Well okay, not next week, but that's the idea anyway, that it'll happen much sooner thanks to our carelessness. I understand that some believe there's no reason to suspect that humans have impacted the Earth's natural cooling cycle at all, and that the hole in the ozone layer is made up, or should be there anyway, or whatever. To that I say, the only way to know for sure is to go back in time and not invent coal burning, etc. and see how things play out 100 years later. But... that's not gonna happen, so we may as well err on the side of caution and do what we can to prepare for what's coming... sunblock SPF 10 million, lots of blankets, prolly should start making underground fortresses, or researching ways to move to another planet or something.