Anthony Watts has a new post on Watts Up With That (WUWT) called Humor: climate delegates unaware of the pause in global warming. Maybe this is funny, but more because the views presented in the WUWT post are tragic rather than because it is typically comedic. The premise of the post, as the title indicates, is that global warming paused 16 years ago and, according to Anthony, it is funny that many delegates at the UN climate conference in Bonn did not know this. There may well be a very good reason why they didn’t know this. It may be simply because it isn’t true.
So, what do I mean by this? What Anthony is referring to is that the trend in the global surface temperature anomalies is not statistically significant. This means that there is a chance (small that it is) that there has been no increase in global surface temperatures since the mid-1990s. However, by the same argument, we can’t rule out that it hasn’t risen quite fast (~ 0.2oC per decade). Furthermore, the trend is positive and the analysis tells us that it is most likely that global surface temperatures have risen, since the mid-1990s, at a rate close to 0.1oC per decade.
Essentially, Anthony is basing his claim on global surface temperature anomalies alone which, although the trend is not statistically significant, do not indicate that there has been no increase in global surface temperatures since the mid-1990s. However, there is another issue. Global warming is about energy, not just about global surface temperatures. It is a process in which the Earth gains more energy from the Sun than it loses back into space. There is extensive evidence to suggest that we are currently undergoing global warming. There are satellite measurements of the energy imbalance. There are measurements showing that the ocean heat content continues to increase. There are measurements showing that the volume of arctic ice continues to decrease (quite dramatically). These are all indicators of global warming. Focusing only on the global surface temperatures ignores many other important and significant (90% of the excess energy is going into the oceans) indicators of global warming.
If there is anything amusing about this (and there isn’t really in my opinion) it is that the author of one of the most viewed sites on global warming and climate change appears not to really understand the fundamentals of global warming. Either that, or he is explicitly trying to mislead those who read his blog. Not actually sure which is worse.