IPCC SPM: “The Pause”
It’s all about temperature.
Much hay has been made over earth’s sea/air surface temperature remaining static since the late 1990s. At least temporarily, earth’s surface temperature – though hot – has leveled off.
The leveling off has become known in skeptic circles as “The Pause”.
The buzz in the climate science universe is what would the IPCC say about “The Pause” in AR5? Wellll… at least in the new “summary for policymakers”, the answer is ‘not much’.
It is instructive to review the SPM to see what it really tells us about “The Pause”.
Earth’s Air/Sea Temperature Profile
Every effect described by the IPCC’s human-caused global warming theory depends on rising earth temperatures. No rise, no effects, no theory.
Therefore, it is no surprise that the very first graphic in the SPM is a timeline plot of the earth’s surface temperature profile since 1850. The IPCC also plots the decadal (10-year) average earth temperature (the bars). The most recent decade, 2000-2009, is the hottest one yet!
But that is not all there is to it. A closer examination reveals there is more to the story than meets the eye.
SPM Temperature vs. CO2
Lets take a closer look at the AR5 temperature profile and throw in a peek at the SPM’s AR5 CO2 profile to.
Since 1850, there looks to have been two distinct phases of temperature rise before the year 2000.
The 1st rise was between about 1920 to 1945 for 25 years bookmarking the dust bowl of the 1930s.
The 2nd distinct rise was for 20 years between 1978 and 1998. Its been steady ever since.
At left, zooming in to look just from 1935 to the present then the infamous “Pause” shows up beginning in the late 1990s.
Importantly, from 1945 to 2000, there was just one 20 year period of temperature rise.
At left is shown the rise of CO2 over roughly the same time period as the temperature rise.
You don’t have to be a climatologist to see the two graphs, though going up, aren’t the same at all.
Clearly, there has to be something more at work in the earth’s climate system then simple greenhouse gas warming.
It surprises nobody that it is natural variability.
If it weren’t for the 20 year temperature rise between 1978 and 1998 then human-caused global warming (AGW) theory would be nothing but a figment of the imagination.
It’s all about temperature!
According to the SPM there has been 0.85°C of warming between 1880 and 2012.
Proponents of AGW theory must explain how, in the last 67 years, there has only been one distinct period of temperature rise lasting only 20 years and that it accounts for 0.6°C of all the warming since 1880; yet CO2 has been rising steadily the whole time before and after.
Clearly, the effects of natural variability are being underestimated.
Furthermore, according to the SPM’s CO2 chart above, about 25% of all CO2 emissions have occurred after “The Pause” began!!
Something’s wrong. The IPCC should address these big concerns but, instead, they ignore them in the SPM.
If “The Pause” lasts a few more years or – GASP! – earth’s temperature decreases then the IPCC’s credibility will be totally lost and AGW theory will go the way of the Dodo bird.
You can only cry wolf so many times before people stop listening.