The Last 25 Years

The last 25 years contain all 15 of the warmest years on record. So should they not also demonstrate that temperatures are unequivocal, unprecedented and accelerating?

Let us use the CO2 datasets and the HADCRUT4 V4.4 temperature dataset to test this expectation.

We know that the 1920-1944 period was a time of rising temperatures.

We have experienced a warmer world over the last 25 years from 1990 to 2014.

Here is the data. Datasets in the links.

Range	CO2 Increase	Temp Anomaly
1920-1944	7.4	.427C
1990-2014	45.5	.446C

That represents an increase of over 6 times the amount of CO2 in our contemporary period of CO2 growth compared to the 1920-1944 period. Based on the constant MSM reminders we are not surprised at the rapid CO2 growth in the last 25 years. It is what we expect.

But the temperature results do not resemble what we would expect from the unprecedented and accelerating description that we keep hearing about. An increase of .019C over the earlier decades does not seem sufficient to justify a fear of rising CO2. These two periods of warming are remarkably similar with vastly different increases in CO2. Does that not allow us to question the supposed unequivocal connection between CO2 and temperature? Isn’t this a poor demonstration of the alleged heat trapping superpowers of CO2?

What temperature increase for the 1990-2014 period would cause you worry? Double, triple, quadruple the earlier period?

DISCLAIMER:

Those were the numbers obtained when this post was created. HADCRUT4 goes through revisions and the next update may change the temperature differences slightly. You might want to ask yourself why a DATA dataset would have a version attached to it. DATA is not a computer program whose code is updated with bug fixes and new features.