After a few arguments with some acquaintances recently, I feel the need to clarify a few things about the science involved here. For one, the people denying that the changes are occurring clearly haven't even done their own research; I've yet to have someone provide even a single reputable source for any claims being made. By reputable, I mean a recent peer-reviewed scientific article, not coverage in the mainstream media by journalists whose coverage isn't worth calling news. At the very least, an article out of an established, reputable scientific magazine would suffice, but the only "facts" I've been presented are articles on Fox that are usually self-contradictory and easily debunked with about thirty seconds of searching on Google. If there were, in fact, a significant controversy over whether or not made-made global warming is a considerable threat to our future, why haven't there been serious studies by independent scientists that have found issues with the current consensus?
Even if you want to discount the data from the UK climate scientist over those hacked e-mails - the contents of which have been taken wildly out of context and overblown - that eliminates just one data set out of thousands out there, all of which point to a significant warming trend in the last few decades. In addition to things merely being taken out of context, there are terms being used that are perfectly understood by the audience (fellow researchers) even though their meanings are very different than would be used by the population at large. The obvious example is the remark about hiding the decline. The "decline" being referred to is a decline in temperatures as reported by the tree ring record, which is contradicted by the actual temperature measurements being taken at the time. Those who are complaining about this are, in effect, arguing that tree records are more reliable than thermometers.
Of those other data sets, NASA's data from weather stations puts the last significant trough at 1966. I've chosen that particular graph to eliminate even the complaint that the models are skewed; the data in that graph are taken from direct measurements, not extrapolations. The land-ocean graph looks roughly the same. The same graph also calls into question the allegations of a natural 30-year cycle, as there is a huge spike between the mid-60s and about 2000, followed by a period of relative stability; if there were a cyclical variation we would be experiencing a corresponding downturn in global temperatures. While the temperatures in the US this year have been exceptionally cool, they've been more than offset by sweltering heat in other parts of the world, particularly in Asia and the Arctic.
So why haven't temperatures risen much in the last decade? A fair question. Perhaps it has something to do with the sun being in one of its longest and deepest solar minima on record. Perhaps it's that the north pole ice is absorbing a lot of that heat energy, as evidenced by the drastic drops in arctic sea ice with the lowest level ever occurring in 2007 and the third-lowest in 2009. Perhaps it really is just a natural variability that's offsetting the human influence on the climate. I've no doubt that there will be plenty of research into it and answers in the coming years.
Tackling the issues facing the world won't be cheap. The plan itself isn't easy to outline and it'll be different in the various parts of the world. But the time to act is now, not in decades to come. The longer we wait, the more difficult it will be to turn things around and the greater the risk of reaching a point of no return.
