The repeated assertions that AGW has been debunked are severely overstated. I've looked at all the counter arguments, and none have yet to pan out. I already shown facts that debunk the utterly false notion that the oceans have risen appreciatively in the last 6000 years before recent times. I've also linked data that shows the temperatures in the last few years are warm by historical measures. I've shown the tree ring problem is overblown, and the trees in question are a divergent subset of all trees sampled, and are the only specimen which does not correlate. The majority of tree ring data correlates well with measured temperature, as well as other proxy data. Other data such as ice cores and sediments have also been shown to correlate. So far, I've seen nothing that proves otherwise. As well, I haven't seen a large and/or growing chorus of scientists who have decided to cease believing in the established science. Just repeating these highly questionable notions aren't going to make them true.
Now, there have been questions raised about the "hockey stick" temperature graph, and how the MWP obliterates it. But, as with all the counter arguments I've investigated so far, this one falls apart when examined closely. Look at the graphics on
this site. Notice that during the MWP, the GLOBAL temperatures were much cooler than they are today. It's striking to notice that although there was some regional warming, it does not significantly impact the hockey stick graph. It appears to be a case of turbulent regional heating and cooling rather than a global trend. So, as I've discovered to be the case with nearly all the counter arguments, the effectiveness of using this information to counter AGW depends on using incomplete data, and it falls apart when closely examined. This has been a pattern from the start, and once that pattern emerged, it's easy to surmise that's going to be the MO for most of the arguments being made, and can be assumed by anyone reading them.
And the reason it is important to pay attention to AWG should be very easy to understand, and self-explanatory. Suffices to say we aren't prehistoric man anymore, and are very dependent on a global economy as well as a small temperate region of the earth which the vast majority of the world's food is grown. That's why scientists are blowing the warning horn, not for fame or fortune, but because they are concerned for mankind and want to ward off any man-made mass extinction. It is their adopted responsibility to try to make things better for people, just as they have done by eradicating disease, inventing new medicine and medical procedures, developing storm early warning systems, etc. We love science when it saves the life of a loved one, but hate it when we think we might have to change bad habits to make life better for everyone.