Even with the strong surge in global temperatures from the current El Niño and from the surge of 2015 global warming exaggeration and fabrication (here, here and here), there remains the strange case of establishment climate science models failing to meet expected outcomes.
Case in point. This chart replicates the famous climate model output presented to Congress and the world in 1988 by James Hansen, the then chief climatologist of the NASA/GISS climate research unit. (Here is an image of the original chart.)
The climate model predicted annual temperature changes would follow the bright green curve if greenhouse gases (GHGs) were not curtailed. GHGs include: CO2, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride - the latter 3 are known as fluorinated greenhouse gases.
The orange curve represents the predicted annual temperature changes if the GHG growth rate were reduced over time.
The chart's cyan (aqua) curve datapoints are the predicted annual temperature changes if GHGs were curtailed by governmental polices and regulations so that year 2000 and beyond had a net growth rate equal to zero.
From the Hansen 1998 testimony, there is this statement:
"We have considered cases ranging from business as usual [BAU], which is scenario A, to draconian emission cuts, scenario C, which would totally eliminate net trace gas growth by year 2000."
From the 1988 Hansen peer-reviewed article that supports his testimony, there is this statement:
"We define three trace gas scenarios to provide an indication of how the predicted climate trend depends upon trace gas growth rates. Scenario 'A' [chart's green curve] assumes that growth rates of trace gas emissions typical of the 1970s and 1980s will continue indefinitely; the assumed annual growth averages about 1.5% of current emissions, so the net greenhouse forcing increases exponentially. Scenario 'B' [chart's orange curve] has decreasing trace gas growth rates, such that the annual increase of the greenhouse climate forcing remains approximately constant at the present level. Scenario 'C' [chart's cyan curve] drastically reduces trace gas growth between 1990 and 2000 such that the greenhouse climate forcing ceases to increase after 2000."
So.....since NASA's top climate expert's testimony, what has happened with the GHG growth and growth rates?
From a recent U.S. EPA report on non-CO2 greenhouse gases, there is the following:
"Global non-CO2 emissions are projected to increase significantly between 2005 and 2030 unless further actions are taken to reduce emissions...total emissions of non-CO2 greenhouse gases have nonetheless increased."
From the latest IPCC AR5 climate report, we know the following about GHGs (a synopsis here):
"Total anthropogenic GHG emissions have continued to increase over 1970 to 2010 with larger absolute decadal increases toward the end of this period. Despite a growing number of climate change mitigation policies, annual GHG emissions grew on average by 1.0 gigatonne carbon dioxide equivalent (GtCO2eq) (2.2 %) per year from 2000 to 2010 compared to 0.4 GtCO2eq (1.3 %) per year from 1970 to 2000. Total anthropogenic GHG emissions were the highest in human history from 2000 to 2010 and reached 49 (±4.5) GtCO2eq/yr in 2010.".....
In addition, the combination of CO2 fossil fuels emissions and CO2 emissions from deforestation, forest fires and peat burning have grown from 72% of all GHG emissions in 1970 to 76% of all GHG emissions.
Regarding fossil fuel CO2 emissions, specifically (CO2 data here): NASA and Hansen's 'BAU' Scenario A was proposed at a time when CO2 emissions were growing: since 1972, the 15 years ending 1987 the world emitted 285 billion tonnes of CO2. This represents a CO2 average growth rate of 2.2% per year for those 15 years prior to Hansen's 1988 testimony.
In contrast, for the 15 years ending 2014, the world has emitted a total of 467 billion tonnes - that is growth some 1.6 times greater than Hansen's 'BAU'. This represents a CO2 average growth rate of 2.9% per year for the period since 1999.
Without any doubt, both empirically and objectively, NASA's Hansen's projected GHG emissions for 'Scenario A' has easily been exceeded since his testimony in 1988. To state otherwise is a falsehood, categorically.
Now, back to the above chart.
For the year 2015, NASA's model predictions had temperature change for all 3 scenarios declining. Of course, we now know the exact opposite took place with the sharp increase in 2015 global temps.
It is important to note that since the 1988 testimony, the NASA climate predictions have very rarely been correct regarding annual temperature changes. (NASA is not an exception, though - all climate computer models and experts suffer the same level of failure.)
For what it's worth, the chart also shows the 2016 predictions: there is continuing decline for Scenarios B & C, but a sharp spike up for Scenario A to a record calendar year anomaly level.
While global warming alarmists are celebrating 2015 as the "warmest" year ever, the climate model failures clearly point to the absurdity of focusing on peak or trough moments as indicators of informed expertise. Peaks happen and troughs happen, in weather and climate, but pointing to either as scientific proof of computer simulations is not science.
Taking that to heart, the accompanying chart has 3-year average plots of highly adjusted observed temperatures from the NASA and UK climate agencies - the 3-year averages remove the focus from peaks/troughs.
As can be seen, 3-year averages of the GISS and HC4 datasets depict the last 3-year average increase due to the El Niño conditions, and those questionable man-made factors.
Be that as it may, the GISS and HC4 averages still remain closer to the realm of NASA's Scenario C range. As a reminder, the Scenario C predictions are a result of net zero GHG emissions simulated to have started in year 2000, which is yet another galaxy away from reality.
In conclusion, some relevant takeaways on climate models:
1. At this point, now close to 3 decades after NASA's testimony, one can safely surmise that expert climate models can't predict squat. The climate is a chaotic complex that defies even the most sophisticated and powerful forecasting tools.
2. GHG emissions have far surpassed the 1988 "world-will-soon-end" BAU construct - a construct that many alarmists still believe. Yet the predicted positive feedback from BAU has not occurred and thus runaway global warming is, without question, AWOL.
3. The climate models are still absolutely unable to discern either the amount or rate of global warming/cooling that is due to natural forces. The models were designed to purposefully rely on greenhouse gas forcings as their major causal factor, while diminishing natural climate impacts. It's no wonder that climate models remain on a fail path.
4. Based on the model outputs from 1960 to the present, policymakers and the public would be better served by rejecting the alarmist scenarios A and B; instead, moving forward, base all adaption and mitigation policies on Scenario 'C', which would likely produce better outcomes with superior allocation of scarce resources.
The climate models definitely have their important place in the climate researcher's toolbox. They are best suited to advance science's better understanding of our world, but their climate predictions, forecasts and prognostications should never be relied on - they are unreliable and inaccurate.
Update h/t: Video of climate scientist making the same point about climate model failure before a congressional committee on Feb 2, 2016:
Additional climate model charts.