A lot of those are some pretty bad missnomers though. The biggest mistake people make is thinking nature is static when history proves otherwise.
It's natural for entire landscapes to change and species to die out. And on an overall scale it's healthy for the planet. The Bark Beetle and animals moving across locations is nothing new either, it's simply a fact of life. I mean you can't expect insects, mammals, amphibians, and reptiles to respect state boundries, they're going to move around and overtake new areas in the search for survival.
There's also been evidence that we're still exiting the last ice age, which basically means the warming trend we're experiences not only has been slow, but may be totally natural. Does that mean we're not contributing? No, but it also means that it's possible it's a totally natural phenomenon that we're well aware of. The polar ice caps melting is bad but it's also on another cycle. 80 Million years ago there was no northern polar ice cap, the average ocean height was 20 feet higher then it is today, and the average world temperature was almost 10ºF warmer then it is now.
I realize Al Gore is trying to do good for the planet (though he's a hypocrit, since his home has one of the worst energy use standards in the country, and he even borrows energy tokens to pay for it). But you can't take "An Inconvienent Truth" as fact because a lot of the science he's proposing in there is still speculative.
There's a lot to this issue which hasn't been addressed, and others which are said to be fact when they are, in fact, not studied for long and well enough to conclusive prove it's existince. My point being is actually study the facts for yourself and don't rely on scare tactic movies like "An Inconvienent Truth" to sway your opinions. By and large the scientific community agrees that global warming does exist, the debate is weather man caused the whole thing or it's a natural trend (which happens on a 20,000 year cycle).
There's a lot to nature and weather that's often used as a scare tactic that simply isn't true. I've been told as many as 7 species will become extinct each year. And I've heard that as many as 10 new ones may emerge. The total bio-mass of the planet is really no less now then it was hundreds of thousands of years ago, it's just been changed, evolved, or died out. The cycle of life is what this is really about, and simply put there's just not enough we know about it in the 400 years of true study we've done on the subject to diffinitively say "the world is coming to an end!"