HadCRUT Data Rank Analysis (III)

Click here for HadCRUT Data Rank Analysis (I)
Click here for HadCRUT Data Rank Analysis (II)
Click here for HadCRUT Data Rank Analysis (III)
Click here for HadCRUT Data Rank Analysis (IV)
Click here for Results of HadCRUT Data Rank Analysis (V)

Let’s have a look now at the graphs for yearly averages, ranked from #0 (coldest) to #157 (warmest) for the period 1850-2007. Source is once again the HadCRUT data.

We are looking for trends, so instead of simply taking the published average temperatures for the year, I have averaged the monthly ranking for each year taken into consideration. There is anyway no considerable difference between the results of the two approaches.

Fig. 1: Yearly temperature rankings between 1850 and 2007

Figure 1 above shows the rankings for the whole period. Things to note:

(a) There is a clustering of warmer years during the past 20 years or so. This does suggest an overall warming. Taking the HadCRUT data for good (otherwise there would be no point examining them), it is also possible to say that the “warmest X years happened within the past Y years”.

(b) The steepest gradient IN TERMS OF RANKING  is by far between the cold years around 1910 and the warm years around 1938.

(c) All the graphs end up with a “cap”

Fig. 2: Yearly temperature rankings between 1997 and 2007

To investigate point (c), Figure 2 above shows the rankings for the past 10 years. Things to note:

(d) Only Land/Northern-Hemisphere gives any indication of continuous warming to date.

(e) Temperatures in the Southern Hemisphere have not been warming on a decadal scale.

I have been notoriously bad at making predictions but on the basis of figures 1 and 2 it is plausible that at least for now, and at least everywhere but on Land/Northern-Hemisphere, temperatures have reached a high and may not increase further.