It is very cold here in the Eastern US and the President is joking about the lack of global warming. More interesting by far is the fact that there appears to have been no CO2 induced warming in the last 40 years, which is as far back as the satellite measurements go.
That this incredible fact has gone unnoticed is due mostly to the scientific community’s fixation on the warming shown by the surface temperature statistical models. But as explained here, these complex computer models are completely unreliable.
Also, the satellite measurements do show some global warming, which people have mistakenly assumed somehow supports the hypothesis of human caused, CO2 induced warming. Careful inspection shows that this assumption is false. There is in fact no evidence of CO2 warming in the entire satellite record.
To see this one must look at the satellite record in detail. To understand this, bear in mind that science is all about the specific details of an observation. These details can overthrow grand theories that are widely accepted.
For example, the negative result of the Michelson-Morley experiment led to the revolutionary special theory of relativity. When it comes to global warming, the 40 year satellite measurements provide a strong negative result for the CO2 warming hypothesis. The CO2 warming just is not there.
To see this negative result, let us look closely at this graphic.
It gives the monthly almost-global temperature readings for the lower atmosphere. The satellites do not cover the entire globe, just most of it. There is also a red line showing a 13-month running average temperature.
Note that on the vertical scale the temperatures are shown as what are called anomalies, not as actual temperatures. An anomaly here is the difference in degrees Celsius between the actual temperature and an arbitrarily chosen average temperature. That average temperature defines the zero line in the graph. Why this is done is not important for our discussion.
To begin with look at the period from the beginning to 1997. The red line shows that this is what is called an aperiodic oscillator. It is an oscillator because it consistently goes up and down, up and down, etc. It is aperiodic, as opposed to periodic, because the ups and downs are somewhat irregular.
It should be clear by inspection that there is very little, if any, overall warming during this period. That is, the red line is oscillating around roughly the -0.1 degree line.
When you have an aperiodic oscillator with this few oscillations there is no point in trying to be extremely precise, because the next oscillation might change things a bit. In particular, one must be very careful in doing straight line (that is, linear) trend analysis, because the result will be very sensitive to where you start and stop the trend.
So let’s just say that there is little or no warming during this period. This was well known at the time and it was a major issue in the climate change debate.
Then comes what is often called the giant El Nino, although it is actually a giant El Nino-La Nina cycle in ocean circulation. First the temperatures go way up, then way down, before stabilizing back into a natural aperiodic oscillator.
The giant El Nino-La Nina cycle looks to begin mid-1997, interrupting a downward moving aperiodic oscillation. It ends sometime in 2001, followed by a new aperiodic oscillation. However, this oscillation is warmer, centered roughly on the +0.15 line. The new oscillator continues until another big El Nino-La Nina oscillation hits, around 2015. What this last El Nino cycle will do remains to be seen
Thus the graph looks to have basically four distinct periods. First the little-to-no warming period from 1979 until 1997. Second the giant El Nino-La Nina cycle from 1997 until 2001. Third, the warmer little-to-no warming period from 2001 to 2015. Fourth the new El Nino-La Nina cycle that is still in progress.
Yes there is some warming but it appears to be almost entirely coincident with the giant El Nino-La Nina cycle. The simplest explanation is that the second flat aperiodic period is warmer than the first because of the El Nino effect. Perhaps some heat was injected into the atmosphere that remained, thereby increasing the baseline for the next aperiodic oscillator.
But in no case is there any evidence of CO2 induced warming here, nor of any human-caused warming for that matter. These causes would produce a relatively steady warming over time, not the single episodic warming that we clearly see here. In particular, to my knowledge there is no known way that the gradual CO2 increase could have caused this giant El Nino-La Nina cycle.
Thus the little warming that there is in the last 40 years appears to be more or less entirely natural. In any normal science this result would be sufficient to invalidate the hypothesis that the increasing CO2 concentration is causing global warming.