Paper Reviewed:
Huang, J., Ou, T., Chen, D., Lun, Y. and Zhao, Z. 2019. The amplified Arctic warming in recent decades may have been overestimated by CMIP5 models. Geophysical Research Letters 46: 13,338-12,345.
Policies aimed at protecting humanity and the environment from the potential effects of CO2-induced global warming rely almost entirely upon models predicting large future temperature increases.
But what if those predictions are wrong? What if a comparison between model projections and observations revealed the models are overestimating the amount of warming?
Would climate alarmists admit as much and back away from promoting extreme policies of CO2 emission reductions?
Probably not — at least based upon the recent rhetoric of each of the candidates seeking the Democrat Party’s nomination for President of the United States, all of whom continue to call for the complete elimination of all CO2 emissions from fossil fuel use within the next three decades, or less.
But for non-ideologues who are willing to examine and accept the facts as they are, the recent work of Huang et al. (2019) provides reason enough to pause the crazy CO2 emission-reduction train.
In their study, the five researchers set out to examine how well model projections of Arctic temperatures (poleward of 60°N) compared with good old-fashioned observations.
More specifically, they used a statistical procedure suitable for nonlinear analysis (ensemble empirical mode decomposition) to examine secular Arctic warming over the period 1880-2017.
Observational data utilized in the study were obtained from the HadCRUT4.6 temperature database, whereas model-based temperature projections were derived from simulations from 36 Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate models (GCMs).
The key results are depicted in the figure below.
Figure 1. Observed and model-predicted rates of nonlinear, secular warming in the Arctic (60-90°N) over the period 1880-2017. The black and red dashed lines indicate the 10th and 90th percentiles for temperature means. Adapted from Huang et al. (2019).
As indicated there, the model-estimated rate of secular warming (the solid red line) increased quite sharply across the 138 year period, rising from a value of around 0°C per decade at the beginning of the record to a value of 0.35°C per decade in the end.
Observations, in contrast, started off with a higher warming rate than that of the models (a rate of 0.13°C per decade; the solid black line) but dipped below the rate of warming predicted by the models around the middle of the record, thereafter experiencing a lower rate of warming relative to the models through the end of the record.
By the end of the record, the model-predicted secular rate of warming was 67% higher than that determined from observations (0.21°C).
Thus, the figure shows an increasing disparity between modeled and observed warming rates that starts around the middle of the record and grows to 14°C per decade by the mid-2010s.
In commenting on these findings, Huang et al. state the obvious, that “anthropogenically induced secular warming has been overestimated by the CMIP5 GCMs during the most recent warming period, and the overestimation is aggravated with time.”
What is more, given the error bars shown on the figure, in the very near future the observed warming rate will likely soon fall outside the significance levels of the ensemble model mean, removing any remaining credibility left in the model projections of future Arctic warming.
With regard to why the models are over predicting modern warming, the five researchers say “it is hard to figure out whether the overestimation of the secular Arctic warming rate mainly comes from an inaccurately simulated change of Arctic sea ice extent or effects of associated physical processes under increasing anthropogenic emissions.”
Our bet is on the latter explanation.
The models are likely running too hot because they overestimate the warming power of rising atmospheric CO2 (see our video clip Is Rising Atmospheric CO2 Causing Dangerous Global Warming? to learn why).
Read more at CO2 Science
The M.S. Media prefer to listen to the liberal crack-pots that come up with the most stupid ideas ever and interview hese lose nuts as well
This is part of a larger pattern. Computer models always predict things will be warming or worse than actual observations. The computers work fine. The problem is the people creating the models let their political motivations drive their design.
Computer models are designed mainly to test variables which feed into a greater, more complicated system. The fantasy of trying to model a global climate with a model is just that – fantasy. the Warming alarmists like to use the poles for several reasons, all of which help to feed their campaign: very few people are in a position to validate the findings directly (visually), the polar ice flucturates greatly and often for many reasons not directly related to ambient temperature. those fluctuations also typically take place well after (days to months) the forcing variable has applied to the region under study. I could publish a claim that Hell froze over last week, and nobody would be able to refute me authentically, except to make clear that Hell is just an imaginary location.
This is no problem for the alarmist. Just change the original temperatures adding “correction” factors, and viola! Models are accurate again. Until they aren’t.
Why the fixation on the Earth’s poles? We have satellites capable of providing accurate temperature data, daily. Polar ice seems to get measured only twice per year. It was the warmists who chose polar ice melt as proof of AGW . Nobody lives there. What incentives do we have to go to the north or south poles? The ship of fools did it for us, free.
The Models are only as good as the person who is feeding in the data and manipulating the Computer using these models to make laws or treaties is irresponsible and foolish