Tag Archives: Surface Temperature Record

Global Warming Hiatus?

Just a quick item on the pause in global warming that is said to have happened over the last X number of years. I took NOAA’s instrumental record since the late 19th century and calculated the average deviation for “surface” temperatures from a baseline for the entire period. Surface temperatures refer to the lower part of the atmosphere and sea surfaces. When you look at a graph of “global warming” expressed in temperatures, this is almost always what is meant (this leaves out a lot of things, including the poles, much of Africa, and deeper ocean waters). But it is a standard and a fairly useful one.

If there was a significant pause in the overall upswing of temperatures for any period of time, I reasoned, it would show up as a cluster of negative years … years where the temperature for that year is lower than the previous years. More to the point, “hiatuses” (and I actually don’t like that word because it is being used correctly …. “pause” is a better word) if they happen on a regular basis should show up as a cluster, not necessarily continuous, of negative years.

Look at the graph above. This is simply a graph that shows a point for each year that is cooler than the previous year. There are tests that one could do on this data. For example, a sign test or a run test would tell if there was any clustering of negatives. But I’m not going to bother with this at this point.

It seems to me that negative years are fairly uniformly distributed at the large scale and seem random. There may in fact be some real clusters in here, but if they are, they are not recent.

So there you go.