Guest Post by Ira Glickstein
I just updated my December 2012 IPCC “Arrows” animation based on the latest available IPCC AR5 (2013) Global Warming prediction for 2035. One good result is that the midpoint of the AR5 prediction range for 2035 is LOWER than the corresponding predictions for three out of the four previous Assessment Reports. Only the Second Assessment Report (SAR – 1995) has a midpoint lower than the AR5 2035 midpoint. The First (FAR – 1990), Third (TAR – 2001) and Fourth (AR4 – 2007) have midpoints for 2035 that are higher than the midpoint for the AR5 prediction! Thus, with AR5, the IPCC has, at least to some extent, “seen the light” and backed down a bit on their predictions of future warming.
On the other hand, the SLOPE of the AR5 prediction is about as steep as the slope of the FAR and AR4 predictions, and even steeper than the SAR and TAR. The reason for this fixation on very steep Global Warming increases is that ALL IPCC models are firmly wedded to ECS estimates at least twice (and possibly three times) as high as they should be. (ECS “Equilibrium Climate Sensitivity” is how much temperatures are expected to increase due to a doubling of Atmospheric CO2.)
(click image to start animation)
It appears the IPCC has learned very little from the abject failure of any of their previous Assessment Reports to comport with the actual temperature record that shows no appreciable warming for 17 years. Without a doubt, IPCC analysis methodology and computer models continue to be seriously flawed. They have way over-estimated the extent of Global Warming since the IPCC first started issuing Assessment Reports in 1990. When actual observations over a period of more than two decades, during which CO2 levels have continued their rapid rise, substantially contradict predictions based on a given climate theory, that theory must be greatly modified or completely discarded.
The Base graphic in the above animation is from the middle panel of TFE.3, Figure 1 (page TS-96) of the IPCC “WORKING GROUP I CONTRIBUTION TO THE IPCC FIFTH ASSESSMENT REPORT, CLIMATE CHANGE 2013: THE PHYSICAL SCIENCE BASIS, Final Draft Underlying Scientific-Technical Assessment. A report accepted by Working Group I of the IPCC but not approved in detail”, available here.
My animation consists of four frames: 1) Base graphic, 2) Black circles that indicate the official Temperature Anomalies (w.r.t. 1961-1990) for the years the FAR, SAR, TAR, AR4, and AR5 were issued. 3) Arrows from the temperature anomaly circles to the midpoints of IPCC predictions for 2035, and, finally, 4) my guess for 2035, which is no NET change from 2013.
IPCC PREDICTIONS FOR 2013 TEND TO BE HIGH
The non-animated graphic illustrates the failures of previous IPCC Assessment Reports. Look above the “AR5 2013” black circle that indicates the current temperature anomaly and you will see that the arrows all pass well above that circle, with the sole exception of the SAR arrow, which is pretty close, but still a bit high.
RATIONALE FOR MY “GUESS” THAT “NO NET CHANGE” WILL PROVE TO BE CLOSER TO THE TRUTH THAN ANY IPCC PREDICTION
I call my projection a “guess” because, as a non-expert on matters of climate, I do not pretend to really know what the future holds. I only wish the IPCC and their allied “Warmists” and “Alarmists” were as modest about their lack of real knowledge about the distant future.
My “guess” is based on four factors:
1) IPCC ECS estimates are two or three times too high. I believe the true ECS is closer to 1°C than the 2°C to 3°C claimed by the official climate Team. If I am correct about the true value of ECS, and if as expected CO2 levels continue their rapid rise (largely due to human activities such as unprecedented burning of fossil fuels), we will continue to experience substantially less human-caused Global Warming than calculated by the IPCC models. Given the stabilization of global temperatures for 17 years, in the face of the continuous rise in CO2 levels, it seems impossible that the claim that CO2 is the MAJOR cause of warming could be true.
2) Daytime clouds, thunderstorms and related natural phenomena have net cooling effects. The way these phenomena are modeled by the IPCC models is basically wrong. I subscribe to the Thermostat Hypothesis put forth in 2009 by Willis Eschenbach that these phenomena counteract some of the warming effects of greenhouse gasses. For example, thunderstorms tend to cool the Surface, daytime clouds increase the albedo (reflectiveness) of the Earth system, and, therefore, when thunderstorms and daytime clouds occur earlier in the day, or there are more of them, that regulates Surface warming to some extent.
3) We seem to be entering a downturn in the multi-decadal cycle of warming and cooling. There has been a general warming trend as the Earth recovers from the “Little Ice Age” which lasted from about 1350 to 1850. An approximately 60-year cycle of warming and cooling seems to be superimposed on that general warming trend and we appear to be near the beginning of a downward trend in that cycle, likely to continue for several decades.
4) The current Sunspot cycle is quite weak and may signal the start of a new cooling period similar to the Dalton Minimum. Cycle #24 has peaked at 67 in the summer of 2013, which is considerably lower than the previous cycle #23 that was nearly twice as strong and peaked in 2001. The Dalton Minimum, from about 1790 to 1830, had a series of low-peaking cycles which coincided with a period of cooling of about 1°C. If Sunspot cycles #25 and #26 are also weak, we may have entered a multi-decadal cooling period. According to Henrik Svensmark’s cosmic ray theory, changes in Solar activity that we observe as a series of stronger or weaker Sunspot cycles has an effect on cosmic rays which, in turn, has an effect on cloud formation. The net result is that weaker Sunspot cycles increase cloudiness, which, in turn, increases the albedo (reflectiveness) of the Earth system, which has a cooling effect. Thus, a series of weak Sunspot cycles could bring us some serious cooling that will counteract any Global Warming due to continued CO2 increases.
(NOTE: Back in 2006 NASA predicted that Cycle #24 would be stronger than #23 and would peak at 156 to 180! Then, in 2008 they reduced their prediction to 137 and in 2009 they reduced it further to 104, which would make #24 a bit weaker than #23. At that time, on my personal Blog before I became a Guest Contributor to WUWT, I predicted #24 would peak at 80. See my 2010 WUWT posting that recounts NASA’s Sunspot roller coaster!)
I’m optimistic about the future! Unlike some of the Alarmists and Warmists who actually hope for a climate catastrophe to justify their decades of shrill Catastrophic Anthropogenic Global Warming (CAGW) warnings, I’d prefer a future without such problems. Indeed, I hope that the cooling trends listed above do not result in excessive cooling which would be far more dangerous than the moderate warming we have experienced over the past century.
PS: For the record, the caption for the applicable part of the IPCC figure I used as the base graphic for my animation is:
TFE.3, Figure 1: …(middle: left) Estimated changes in the observed globally and annually averaged surface temperature anomaly relative to 1961-1990 (in °C) since 1950 compared with the range of projections from the previous IPCC assessments. Values are harmonized to start form the same value at 1990. Observed global annual temperature anomaly, relative to 1961–1990, from three datasets is shown as squares (NASA (dark blue), NOAA (warm mustard), and the UK Hadley Centre (bright green) data sets. The coloured shading shows the projected range of global annual mean near surface temperature change from 1990 to 2035 for models used in FAR (Figure 6.11), SAR (Figure 19 in the TS of IPCC 1996), TAR (full range of TAR, Figure 9.13(b)). TAR results are based on the simple climate model analyses presented in this assessment and not on the individual full three-dimensional climate model simulations. For the AR4 results are presented as single model runs of the CMIP3 ensemble for the historical period from 1950-2000 (light grey lines) and for three scenarios (A2, A1B and B1) from 2001-2035. For the three SRES scenarios the bars show the CMIP3 ensemble mean and the likely range given by -40 % to +60% of the mean as assessed in Meehl et al. (2007). The publication years of the assessment reports are shown. (middle; right) Projections of annual mean global mean surface air temperature (GMST) for 1950–2035 (anomalies relative to 1961–1990) under different RCPs from CMIP5 models (light grey and coloured lines, one ensemble member per model), and observational estimates the same as the middle left panel. The grey shaded region shows the indicative likely range for annual mean GMST during the period 2016–2035 for all RCPs (see Figure TS.14 for more details). The grey bar shows this same indicative likely range for the year 2035. …