Be careful about disbelieving what the majority (most would say vast majority) of scientists say about climate change in favor of extrapolations based on one (or many) year's data.
Charlie,
What you've written there is basically what has been used to tell us that global warming is anthropogenic (remove the "dis" in front of "believing" though). It's not a scientific debate at all sadly - it's a political one. Short term data can be used to prove global warming by scientists / The Media but not to discredit it.
Accurate measuring of climatic conditions has not been around for more than a couple of generations (and many would argue that the data still is not accurate due to a number of reasons). That's an unbelievably small percentage of the lifetime of the planet. It's been colder before. It's been hotter before. It will be colder in the future, it will be hotter in the future.
It's impossible to state from the available data what is causing any temperature change in the planet. There are too many variables, and the computer models are only as good as the data they are given (see the discredited "Hockey Stick" for proof of that).
Tom,
As I see it you bring up two issues. I'll paraphrase them as:
1. Don't believe everything you're told, especially by the politicians and media.
and
2. Accurate measurements haven't been around long enough to justify the predictions being made.
If I'm terribly far off, let me know, but I don't want to get involved in a semantic brouhaha.
To 1, I'd say that I'd be more concerned as to what their sources are. I am not a climatologist or scientist. Therefore unless I want to decide based on a wholly ignorant opinion (my own), I must listen to someone who knows what he or she is talking about. For me, this has meant talking to a close friend who is a scientist (technically a grad student) and finding out what would be a credible source. She pointed me to the Intergovernmental Panel on Climate Change. This organization is the largest organization of climatologists in the world and its last report was fairly unequivocal about the scale and scope of the climate change problem. Since no organization of remotely similar size and respect exists, the evidence and (more importantly) interpretations that they have offered is the one I've chosen to believe. Could they all be lying? Yes, but it's no more likely (I'd call it less likely) than the possibility that those on the other side of the issue are lying. Since in the realm of science (at least in my book) Tie goes to side with the majority of more-qualified scientists, I believe the IPCC.
As to number 2, I'd say that only a scientist can really know what is good enough. I've mentioned the ice cores that can contain evidence (which is different than data) from long, long ago.