Global warming is one issue that I'm not convinced of on either side. Maybe convinced isn't the right word...I'm just not sure where I stand on this.
It has gotten a little warmer, averaged world wide. And the rapidity of the warming is much faster than it has been in the past. Those things we know from thermometers and ice core samples. We can't deny the substantial shrinking of the glaciers and the subsequent rise in sea level, either. But whether it can be stopped or whether CO2 has anything to do with it is the question. These deniers, on the other hand, apparently are deeply suspicious of thermometers.
No --- not suspicious of thermometers in the 20th century anyways. But I AM suspicious about the hysterical claims that it's "warming faster than the last xxx Thousand years". Because -- there were no thermometers. And you don't find ice cores GLOBALLY, and tree rings are NOT great thermometers, and the little mud bug shells also used in proxies for those "ancient" temperature studies can't be accurately dated because the little buggers dig and burrow in what is 100s of years of vertical mud in those "core samples". So the bottom line is -- the 0.8degC warming in your lifetime is probably NOT truely exceptional looked at on a climate scale of thousands of years. And all those "proxy studies" lack the time resolution and distributed spatial sampling of the globe to FIND a 1degC change over a 100 years. In fact, they can not find much in the way of variance over spans of 300 to 500 years. So no real conclusions can be made about "natural climate variabilty" from them. Although -- it's now a form of urban legend that they "proved it". .
The rate of warming is NOT increasing as predicted, and most of the 1980s predictions have already failed. CO2 plays a ROLE in this probably, but is NOT the dominant apocalyptic trigger to destroy the planet that it's been made out to be.