re: #241 Dark_Falcon

Ludwig, question: How do you answer the “cold decade” argument with a view to winning over the arguer?

Well it is interesting that you say it that way.

If the person is actually making that argument in a way that can be reached, as in “I have heard about no warming… is that rue?”

Then I would say the following.

First off, the assertion is not true. If you look at data from year to year, you will see that the graph is not smooth, rather it waggles around a trend that persists over many years.

If you have a spike in one year, but the next one is a little cooler, that does not mean a reversal of the over all trend.

consider the following set of numbers:

1, 2, 0, 1, 3, 2, 4, 3, 6, 3, 5, 8, 4, 6, 9, 10, 14, 8, 11, 10, 15, 16, 13, 14

If you look at it, towards the beginning, the numbers are around 1 and 2.

Towards the end, anyone can see that the numbers are around 14 and 16.

Clearly there is a significant rise in the numbers. Clearly if you look at the intermediate numbers as well, the over all trend of the series is growth.

This is exactly what we see (as a pattern) in the climate. This is exactly what has happened. For over a century, the temperatures on the planet have been steadily rising over all.

Here is a graph from NOAA to show that this is the case.

ncdc.noaa.gov

This is direct data from both satellite and ground based and ocean based sensors, thousands of them from around the world. The data is hard to refute, just like it is hard to argue that the series above is not growing.

However, suppose that you wanted to be completely dishonest and use the data to lie to people who don’t know the whole story.

You could pick the end of the series (15, 16, 13, 14) and falsely claim “aha! The sequence is clearly going down!” “We stopped growing when we hit 16!” It’s just that this is false and based on a sort of mathematical con called cherry picking. The entire trend of the series has been to grow.

In the past there were spikes that went down only to be overtaken. There is no reason to assume that the trend to growth has stopped other than wishful thinking or a desire to simply lie.

This is particularly the case with AGW and world temperatures because there are all sorts of well understood mechanisms in place that assure us we will keep warming. Those physical realities did not go away when we saw the temperature spike in the past, and they have not now. In fact, they have been exacerbated and sooner or later, the numbers will grow strongly. In fact if you look at the central mean of the numbers for temperatures, spikes and all, you will see not only is the temp growing, but the average rate of growth is itself increasing.