Shaviv is making an extraordinary claim. He claims that changes in solar activity are an order of magnitude greater than solar irradiance. He bases this claim on a paper authored by him, "Using the oceans as a calorimeter to quantify the solar radiative forcing". Have you read this paper? It is very difficult to understand. Do you understand it? In his abstract to this paper he says: We find that the total radiative forcing associated with solar cycles variations is about 5 to 7 times larger than just those associated with the TSI variations, thus implying the necessary existence of an amplification mechanism, although without pointing to which one. 5 to 7 times is not quite an order of magnitude but it is still an extraordinary claim. I was wondering about the accuracy of his graph showing the reconstructed solar constant. How did he determine the "reconstructed solar constant" for the time period between 1920 and 2000? This is how he explains it: (How accurately known is the thermal heat content of the top 700 m of the global oceans during the 20th century? This must be fairly accurate to make the analysis accurate) " We begin with a direct reconstruction of the global oceanic heat flux using the thermal heat content of the top 700 m of the global oceans over the past 5 decades [Ishii et al., 2006], and differentiate it. Since we do not expect the 11‐year oscillations to penetrate deeper than about 200 m (depending on the mixed layer depth and the actual diffusion coefficient), there is no need to add deeper ocean data, which would just add noise. [29] Two sets are generated, one for the whole ocean and one for the Atlantic region (all waters between 80°W and 30°E). The data is then differentiated to get a flux, and averaged with a 3 year (central) running average. The result is depicted in Figure 4. The flux is the average flux going into the oceans. This is not necessarily the average over the whole globe." Then he compares that graph with a graph of sea level fluctuations from tidal gauges to calculate how much solar energy is being absorbed by the top layer of the oceans. He discusses the possible mechanisms that might explain this solar amplification, but doesn't draw any conclusion. Why do you accept this very difficult to understand science over the much more easier to grasp climate science in the recent IPCC report? His argument is based on something for which the mechanism isn't understood and the data is based on imprecise and probably inaccurate data. Compare that to the data that the IPCC has, paleoclimate studies that show a strong role for carbon dioxide and methane, and mechanisms that are well understood.
No, they are not generally accepted. "Generally speaking, we can observe that the scientists in any particular institutional and political setting move as a flock, reserving their controversies and particular originalities for matters that do not call into question the fundamental system of biases they share." —Gunnar Myrdal, Objectivity in Social Research
It seems to me that there will obviously be a correlation between the reconstructed global heat flux and the thermal expansion of the top layer of the ocean if the global heat flux is calculated from the change in ocean heat content. I'll re-post the relevant portion of the article again. " We begin with a direct reconstruction of the global oceanic heat flux using the thermal heat content of the top 700 m of the global oceans over the past 5 decades [Ishii et al., 2006], and differentiate it. Since we do not expect the 11‐year oscillations to penetrate deeper than about 200 m (depending on the mixed layer depth and the actual diffusion coefficient), there is no need to add deeper ocean data, which would just add noise." He found a correlation and used that correlation to find that the peak-to-trough radiation forcing during a solar cycle .It was 1.0 to 1.5 watts/meter. The total solar irradiance (TSI) change is around 0.2 watts/meter. Therefore, an amplifying mechanism must exist if this data is correct. A very fast-feedback climate sensitivity of around 1.5 to 2.0 cannot account for this. The very fast-feedback climate sensitivity would include water vapor feedback. What accounts for this 5 to 7 fold amplification of the TSI change, assuming that that the data and analysis are accurate? What I question is the accuracy of ocean heat content numbers during the 1920 to 2000 time frame needed to measure small deviations over an 11 year interval. The 1 std. deviation error bars are high as shown by the shaded blue region on the graph. I also question the accuracy of the tidal gauge readings. Millimeters of change must be measured accurately. What accounts for this 5 to 7 fold amplification of the TSI radiative forcing?
Is it your opinion that the sun plays the most significant role in global warming over the past 100 years? What role do you place for greenhouse gases? Even if the sun's effects on the climate are some how enhanced significantly beyond the effects of just total solar irradiance (TSI), that doesn't explain the warming of the Earth's surface over the past 50 years. Which is about 0.19 degrees C per decade. It doesn't explain the cooling at the top of the troposphere or the increased warming at night. This is explained well in a Skeptical Science article, "Sun and climate: moving in opposite directions". https://www.skepticalscience.com/solar-activity-sunspots-global-warming-advanced.htm Inability to explain empirical observations Aside from the fact that solar effects cannot physically explain the recent global warming, as with GCRs, there are several empirical observations which solar warming could not account for. For example, if global warming were due to increased solar output, we would expect to see all layers of the atmosphere warm, and more warming during the day when the surface is bombarded with solar radiation than at night. Instead we observe a cooling of the upper atmosphere and greater warming at night, which are fingerprints of the increased greenhouse effect. No change in the trend in solar magnetic flux, which correlates with solar activity, that can account for global warming since 1970. Figure 3: Solar Magnetic Flux from 1967 to 2009 (Vieira and Solanki 2010) We are currently coming out of a deep solar minimum, yet 2020 will likely be the second warmest year on record. There have been 100 days in 2020 with zero sunspots. Figure 1: Annual global temperature change (thin light red) with 11 year moving average of temperature (thick dark red). Temperature from NASA GISS. Annual Total Solar Irradiance (thin light blue) with 11 year moving average of TSI (thick dark blue). TSI from 1880 to 1978 from Krivova et al 2007. TSI from 1979 to 2015 from the World Radiation Center (see their PMOD index page for data updates). Plots of the most recent solar irradiance can be found at the Laboratory for Atmospheric and Space Physics LISIRD site.
As Shaviv explains in several different presentations, he estimates about half 20th century warming was solar-derived. The other half was anthropogenic. A good presentation is here. Carbon Dioxide or Solar Forcing? ". . . Using historic variations in climate and the cosmic ray flux, one can actually quantify empirically the relation between cosmic ray flux variations and global temperature change, and estimate the solar contribution to the 20th century warming. This contribution comes out to be 0.5±0.2°C out of the observed 0.6±0.2°C global warming (Shaviv, 2005). Fig. 5: Solar activity over the past several centuries can be reconstructed using different proxies. These reconstructions demonstrate that 20th century activity is unparalleled over the past 600 years (previously high solar activity took place around 1000 years ago, and 8000 yrs ago). Specifically, we see sunspots and 10Be. The latter is formed in the atmosphere by ~1GeV cosmic rays, which are modulated by the solar wind (stronger solar wind → less galactic cosmic rays → less 10Be production). Note that both proxies do not capture the decrease in the high energy cosmic rays that took place since the 1970's, but which the ion chamber data does (see fig. 6). (image source: Wikipedia) Fig. 6: The flux of cosmic rays reaching Earth, as measured by ion chambers. Red line - annual averages, Blue line - 11 yr moving average. Note that ion chambers are sensitive to particles at relatively high energy (several 10's of GeV, which is higher than the energies responsible for the atmospheric ionization [~10 GeV], and much higher than the energies responsible for the 10Be production [~1 GeV]). Plot redrawn using data from Ahluwalia (1997). Moreover, the decrease in high energy cosmic rays since the 1970's is less pronounced in low energy proxies of solar activity, implying that cosmogenic isotopes (such as 10Be) or direct solar activity proxies (e.g., sun spots, aa index, etc) are less accurate in quantifying the solar → cosmic ray → climate link and its contribution to 20th century global warming. . . ."
Here you go: cosmic ray flux variations. THE OCEANS AS A CALORIMETER ". . . However, if solar activity is amplified by some mechanism (such as hypersensitivity to UV, or indirectly through sensitivity to cosmic ray flux variations), then in principle, a lower climate sensitivity can explain the solar-climate links, but it would mean that a much larger heat flux is entering and leaving the system every solar cycle. . . ."
NOTHING in that quote suggests that YOUR direction of picking one naysayer is the preferred approach when the vast majority are in agreement.
As a matter of law, ANY privately owned publication can print what it chooses to print and NOT print what it chooses not to print. In other words, this is a free country! Look at Fox. They can doctor videos, cut and paste to make it sound like someone said what they didn't say, take statements out of context to promote conspiracy theories, etc., etc. And, NONE of those actions can be called censorship. The reason is that they are private enterprise and may say and do what they want, as long as they don't step over various requirements of actual damages. I'm noting a certain stuborn streak in your approach here that makes your opinions worthless for the reason that they are not formed in relation to reality.
I recognize this as YOUR personal opinion. The catch is that your personal opinion is of no interest when compared to the combined determination of scientists involved in this domain the world over.
Bolding mine: "Censorship is the suppression of speech, public communication, or other information, on the basis that such material is considered objectionable, harmful, sensitive, or "inconvenient." Censorship can be conducted by governments, private institutions, and other controlling bodies." Wikipedia
Yes, it's my personal opinion. Bolding mine. By Michael Crichton Caltech Michelin Lecture January 17, 2003 ". . . I want to pause here and talk about this notion of consensus, and the rise of what has been called consensus science. I regard consensus science as an extremely pernicious development that ought to be stopped cold in its tracks. Historically, the claim of consensus has been the first refuge of scoundrels; it is a way to avoid debate by claiming that the matter is already settled. Whenever you hear the consensus of scientists agrees on something or other, reach for your wallet, because you’re being had. Let’s be clear: the work of science has nothing whatever to do with consensus. Consensus is the business of politics. Science, on the contrary, requires only one investigator who happens to be right, which means that he or she has results that are verifiable by reference to the real world. In science consensus is irrelevant. What is relevant is reproducible results. The greatest scientists in history are great precisely because they broke with the consensus. There is no such thing as consensus science. If it’s consensus, it isn’t science. If it’s science, it isn’t consensus. Period. . . ." Aliens Cause Global Warming Thursday, January 31st, 2019
That is a MAJOR misunderstanding of Chrichton's concern. The question here in this thread has to do with how public policy is to be informed by science. Public policy can not be rationally informed by picking outliers from the totality of those working in fields of climatology. What we accept from science needs to be some kind of majority conclusion of trusted sources - what the full body of knowledge and expertise concludes is likely (along with how likely). Chrichton's concern is that consensus within science could cause SCIENCE (not public policy) to be stunted by groupthink that is unwilling to consider alternative approaches or refutations. This is also what Dr. Judih Curry, a noted climate contrarian, worried about. She wanted to see a direction within science that would allow contrarian positions to receive more attention by having journals or other outlets where results rejected by mainstream journals could get serious review and greater attention. This is not taken lightly. I am STRONGLY in favor of Shaviv's results being taken seriously BY SCIENCE - at least to the point of incorporation or rejection. BUT, that does NOT mean it is legitimate to pick outliers on which to base our public policy. Chrichton NEVER said that we should take that kind of approach in public policy. That would be an entirely political approach to pumpkin picking what it is that pioliticians might want to believe. Having congressmen searching for outliers that seem to suppot their policy desires does NOT qualify as being informed by science. And, our public policy absoltuely DOES need to be informed by scinece.
Initially, there wasn't a consensus that humans could significantly alter the climate by burning oil, coal, and natural gas. That consensus took about 100 years to develop after much investigation. The process that climate science went through is typical for the development from an hypothesis to a theory, except the process took much longer than normal for climate science. There is a consensus on relativity theory, evolutionary theory, and quantum theory. Are those subjects not science because there is a concensus?
Those examples are of the exploitation of science by unscrupulous corporations and the lack of knowledge about a products harmful effects. They have little to do with modern methods in insuring product safety. No reasonable person says that we should always trust scientific findings so that is a bit of a "straw-man".
The topic on this thread is science denial. That doesn't refer to something going on inside of science - the something that Chrichton talked about. Denying science refers to cases of the public and our government representatives refusing to be informed by sciece. Picking radicals and outliers is not how one goes about being informed by science. It IS possible to have a discussion within science concerning any topic one wants. And, when there is disagreement like that where people ARE listening to specific arguments THAT disagreement can not be termed "science denial".
