Either global warming is the greatest crisis ever to confront humankind, or it is a lefty plot completely manufactured by scientists and politicians in pursuit of research funding and control over our lives. That’s about the way it plays out in the media, on blogs and in conversations on the Metro. Anyone out front on this issue is either an apocalyptic or a denier, virtuous or vile.
Similarly, one camp maintains that temperatures are rising dramatically with unspeakable portents, while the other thinks what has happened is entirely a result of undefined internal oscillations in the earth-sun climate system, and that there is virtually no human component to climate change. This group is especially fond of the lack of statistically significant surface warming since 1995. Since 1997, temperatures really flatlined.
There’s a third way, which suffers from the problem that it is subtle, neither black nor white, and doesn’t do well in sound bites. It’s a “lukewarm” synthesis, arguing indeed that humans have something to do with the rise in surface temperature measured since the mid-1970s, but that it is hardly the end of the world as we know it. This view claims to accommodate the seemingly odd behavior of temperature in the last 15 years.
Each of these positions – let’s call them hothead, flatline, and lukewarm – are testable against observed history and theory. To keep some interest in this occasionally boring topic, I’m going to examine them sequentially, starting with the hotheads.