More from Andy Lacis

Andy Lacis comments on Judith Curry's visit to the hall of mirrors at And Then There is Physics, but in the spirit of the think, allow Eli to repost.
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Let me toss on here what I posted on ClimateEtc in regard to the recent (April 15, 2015) Science, Space, and Technology Committee Congressional Hearing:

As was to be expected, Congressional hearings are more about political posturing rather than being a directed effort of objective information gathering. Naturally, there was the perfunctory public posturing of pretending to appear “fair and balanced”. But the unmistakable overall flavor was really one of there-we-g0-again legalistic tribunes where selected legal briefs are presented on behalf of well-known staked-out positions by convenient plaintiffs who get to argue the virtues of their special points of view on their favorite issues regarding global warming and global climate change.

What went missing in this Congressional climate forum was any kind of real balancing testimony from experts in the field who have spent decades to analyze this important topic of global climate change. Regrettably, there was no real discussion as to what we actually do know about the global warming problem, and why we know it.

But, looking on the brighter side, perhaps there may have been a small modicum of progress having been made in that the likes of Senator James Inhofe (R, Oklahoma) and Congressman Dana Rohrabacher (R, California) were not out there lambasting global warming and climate change as being the greatest hoax ever perpetrated on humanity. It appears that perhaps at this point in time, making such blatant denials of reality could be perceived as being unnecessarily clueless and ignorant.

But then there is also the contrary example of courageous conviction, and understanding of the global warming reality, exhibited by former Congressman Bob Inglis (R, South Carolina), who paid the price for being politically incorrect. One can only hope that at some point, pragmatic sanity will eventually prevail.

Even some of the staunchest of the global warming doubters have now grudgingly come around to acknowledge that CO2 does indeed absorb thermal radiation (but they want to claim that the absorption is small, that CO2 is saturated, and that water vapor actually absorbs more strongly); that while there might have been some increase in global temperature (it all has been mostly due to natural variability, and as such, it has been beneficial); and that while humans might have contributed to the rise in atmospheric CO2 (it has not been significant, and besides, the plants have benefitted from more CO2).

While there was nothing that was specifically erroneous in these Congressional Hearing presentations, it was the usual problem of half-truths, misdirection, and non-sequiturs being used to paint a picture that is not an accurate description of where we stand in our understanding of the current climate situation.

Part of the problem may also be attributable to the flexible nature of some basic definitions. What exactly is meant by this common term “global warming”? Literally, the term “global warming” would signify that the global-mean temperature is rising, and if the global-mean temperature were to be decreasing, the situation would then become “global cooling”. But this frequently used term has also acquired a more technical meaning as it is being used in climate science. As the key cause and principal component of global warming, it is the rise in atmospheric CO2 and other greenhouse gases that act to increase the strength of the terrestrial greenhouse effect, and induce more water vapor in the atmosphere as a feedback effect. This inevitably leads to an increase in global surface temperature. This is really what the term “global warming” represents.

But there are other factors that also affect the global temperature. These can be caused by changes in solar irradiance, volcanic aerosols, and the natural variability of the ocean. Changes in solar irradiance and volcanic aerosols are typically known accurately enough. It is the variability of the ocean that is the principal source of uncertainly, such as a strong negative branch of the PDO cycle that can keep the global temperature from rising while atmospheric CO2 continues to increase unabated.

It is important to remember that the present-day changes affecting the global climate consist of two basic components: (1) the ongoing global warming component fueled by increasing atmospheric CO2, and (2) the natural variability of the climate system that consists of random-looking fluctuations about a slowly evolving zero reference point of the climate system.

It would be a misdirection to suggest that global warming has just somehow stalled simply because there has been only a little rise in global surface temperature since the prominent peak in 1998. There was no comparable “pause” in the rate of atmospheric CO2 increase during this time period. Instead, the global energy imbalance of the Earth increased as the heat energy that would have been warming the ground surface was being diverted toward heating the ocean. This puts more unrealized global warming into the “pipeline”, from which it will be emerging as the PDO cycle shifts toward its positive phase.

The natural variability of the climate system also makes it difficult to infer climate sensitivity to the radiative forcing by atmospheric CO2. Reliable estimates of the equilibrium climate sensitivity (equivalent to about 3 K for doubled CO2) are obtained from the geological record and from climate model calculations. The transient climate sensitivity is by definition a moving target since it depends on the rate of change of heat transport into the ocean (which itself is a changing factor), and estimating the transient climate sensitivity from observational data is particularly difficult (and uncertain), because it is necessary to know all contributing forcings in order to disentangle the feedback contributions from the total climate system response. While the CO2 forcing may be known accurately, it is big uncertainty as to the “virtual” forcings due to the natural variability of the ocean that are the most difficult to determine. Thus, estimates of the transient climate sensitivity (whether high, or low), will continue to remain highly uncertain.

In view of the above, the suggestion that climate models are running “too hot” compared to observations is disingenuous. Climate models may well run “cold” while simulating El Nino events, and run “hot” while simulating the global temperature during a strong negative PDO. Both climate models and the real world exhibit a form of unforced natural variability. And in both cases, this natural variability is quasi-chaotic, with no real way to coordinate the phasing of this variability. Any short-term comparisons between climate model results and observations need to keep this in mind. To sidestep this problem, the time period for comparisons must be long enough for the natural variability contributions to average out.

Granted, the definition of “dangerous” climate change is ambiguous. And there is probably no real way to quantify just what “dangerous” actually represents. Perhaps the example of the Titanic may help.
At what point did the situation on the Titanic become dangerous? There was no perceived danger when the Titanic left Southampton for New York. Most of the passengers were still dry and alive some two hours after hitting the iceberg. Did the danger begin when the iceberg was spotted, but there was not enough time to avoid the collision? Or was the danger already brewing when Captain Smith ignored reports of icebergs and continued full steam ahead? There might be some relevant parallels to draw.

Global-mean winds, global-mean temperatures, and global-mean precipitation, compared between a doubled CO2 climate and the current climate would not appear to be consequentially different. But it is the extreme weather events that cause the damage. Whether humans get blamed, or not blamed, neither adds nor detracts from the problem. Global warming puts more heat, water vapor, and latent energy into the atmosphere. And that is the fuel that makes the extreme weather events more extreme. So, there actually is a real relationship to be had between global warming (human induced) and a growing danger of more severe weather extremes. A better studied quantification of this relationship would certainly be very useful.

It would seem more appropriate to assign “wickedness” to problems that are more specifically related to witches. The climate problem, while clearly complex and complicated, is not incomprehensible. Current climate models do a very credible job in simulating current climate variability and seasonal changes. Present-day weather models make credible weather forecasts – and there is a close relationship. Most of the cutting edge current climate modeling research is aimed at understanding the physics of ocean circulation and the natural variability of the climate system that this generates. While this may be the principal source of uncertainty in predicting regional climate change and weather extreme events, this uncertainty in modeling the climate system’s natural variability is clearly separate and unrelated to the radiative energy balance physics that characterize the global warming problem. The appropriate uncertainty that exists in one area of climate modeling doe not automatically translate to all other components of the climate system.

Besides, the persistent uncertainties regarding the natural variability of the climate system are not the real problem that we face. The real problem is the continued increase in atmospheric CO2 that is causing the ongoing global warming. And, the basic facts and physics for understanding this aspect of global warming are all well established and well understood.

There always seem to be temptations to minimize the consequences of the global warming problem, or the cost-effectiveness of proposed efforts taken or suggested to counteract the global warming problem. That is just what Steven Koonin attempted to do in a previous post, nor does it appear to be different in this Congressional hearing.

Typically, the economic costs of taking action to address the global warming problem are always cited as being unnecessarily excessive. This was true of the proposed expenditure of hundreds of millions of dollars to upgrade the levees and shoreline in New Orleans prior to Katrina, and in New York prior to Sandy. Had this money actually been spent to make New York and New Orleans more hurricane-proof, we might never have known that hundreds of billions worth of hurricane damage might have been averted.

The economic cost of combating global warming is likely to be many hundreds of billions of dollars. But has anybody tried to calculate how many trillions of dollars it would cost to relocate Miami, New York, Washington DC, and New Orleans to higher ground? Surely, there are bound to be many other economic costs to tally up, brought on by the inaction to counteract the impending consequences that global warming is sure to bring.

Clearly, decisions will need to be made, and they will need to be made sooner rather than later. Is there anybody in Congress who is capable of making the hard decisions? It is actually important to first fully understand the problem before deciding to act, or in justifying the decision not to act.