From the CO2Science Archive: In an intriguing paper published in Physics Reports, Qing-Bin Lu – who is associated with three different Departments at Canada’s University of Waterloo (Physics and Astronomy, Biology, and Chemistry) – injects a whole new dimension into the contentious debate over what has been the cause of late 20th-century global warming and its early 21st-century cessation. The bulk of Lu’s paper is dedicated to describing the new cosmic-ray-driven electron-induced reaction mechanism – or CRE model – of ozone depletion, which he contrasts with the conventional photochemical model of ozone depletion. Near the end of his discussion of this other important subject, however, he makes some original observations about the possible effects of chlorofluorocarbons (CFCs) and cosmic-ray-driven ozone depletion on global climate change, which subsidiary analysis gives one pause to wonder if the ire of the world’s climate alarmists has long been focused upon the wrong greenhouse gas, i.e., CO2.
Paper reviewed: Lu, Q.-B. 2009. Cosmic-ray-driven electron-induced reactions of halogenated molecules adsorbed on ice surfaces: Implications for atmospheric ozone depletion and global climate change. Physics Reports 487: 141-167.
Lu begins by noting that ozone-depleting CFCs are also greenhouse gases, but that the IPCC has considered them to provide only about 13% of the total radiative forcing produced by all of the atmosphere’s well-mixed greenhouse gases. He then goes on to challenge the low value of this assessment, stating emphatically (as indicated by his use of italics) that “these conclusions were based on climate model simulations rather than direct observations.” And he thus proceeds to consider some real-world measurements in ways that have not been done before.
In plotting yearly mean global temperature deviations (ΔT, relative to the 1980 mean value) vs. equivalent effective stratospheric chlorine concentrations (EESC, normalized to the 1980 value) over the period 1970-2008, for example, Lu found that the former parameter was a well-defined function of the latter, as may be seen in the figure below, where the correlation coefficient (R) of the linear relationship between the two parameters is 0.89 at a probability level (P) of < 0.0001.
Figure 1. Yearly global temperature relative to its 1980 value (ΔT) vs. yearly EESC normalized to its 1980 value. Adapted from Lu (2009).
Of course, correlation does not prove causation, as climate skeptics are fond of saying about the similar relationship between ΔT and the air’s CO2 content over the latter part of the 20th century. But Lu makes a point of noting that following the implementation of the Montreal Protocol, the total halogen level in the lower atmosphere was observed to peak in 1994 and the EESC over Antarctica was estimated to peak around the year 2000, after which it actually began to decline, as did global temperature, as shown in the figure below. And based on the estimated trend of EESC over the next four decades, Lu’s analysis suggests that the earth may well continue to cool – as it has been gradually doing for the past decade – until the middle of the current century or more.
Figure 2. Yearly global temperature relative to its 1980 value (ΔT) and yearly EESC normalized to its 1980 value vs. time. Adapted from Lu (2009).
As for what it all means, Lu states, in the concluding paragraph of his lengthy treatise, that the “observed data point to the possibility that the global warming observed in the late 20th century was dominantly caused by CFCs, modulated by CRE-driven ozone depletion,” and that “with the decreasing emission of CFCs into the atmosphere, global cooling may have started since 2002.”
Like the good scientist that we presume he is, however, Lu does not contend that this must be the case; he only states that “this is likely a subject deserving close attention.”
The question now is: Will other scientists provide that close attention? With all that is riding on the issue, we sincerely hope that they will.
Qing-Bin Lu! What sort of scientist is he, relying and presenting data and applying quantitative statistical techniques. He has the gall to suggest further research is needed, without claiming the "science is settled." Get out of here Lu!
I have long been a follower of Prof Lu and his work. I like the fact that after positing a theory that seems reasonable, he replicated the chemistry in a chamber in his Waterloo University lab.
Try a correlation with jet aircraft activity. Ozone depleation can occur due to low o2 levels.
UV plus oxygen makes ozone ozone filters UV and infrared. Infrared is what heats solid objects.. Antartic chlorine comes from Mt Erebus emmisions. Other ozone depleting chemicals are also emmitted. The ozone hole ruduces during the summer months.
Here is Lu's newest paper on the topic, which includes his first-principles (parameter-free) quantum-physics calculations of the warming effect of CFCs:
Qing-Bin Lu, Major Contribution of Halogenated Greenhouse Gases to Global Surface Temperature Change, Atmosphere 2022, 13(9), 1419; https://doi.org/10.3390/atmos13091419
Abstract: This paper aims to better understand why there was a global warming pause in 2000–2015 and why the global mean surface temperature (GMST) has risen again in recent years. We present and statistically analyze substantial time-series observed datasets of global lower-stratospheric temperature (GLST), troposphere–stratosphere temperature climatology, global land surface air temperature, GMST, sea ice extent (SIE) and snow cover extent (SCE), combined with modeled calculations of GLSTs and GMSTs. The observed and analyzed results show that GLST/SCE has stabilized since the mid-1990s with no significant change over the past two and a half decades. Upper-stratospheric warming at high latitudes has been observed and GMST or global land surface air temperature has reached a plateau since the mid-2000s with the removal of natural effects. In marked contrast, continued drastic warmings at the coasts of polar regions (particularly Russia and Alaska) are observed and well explained by the sea-ice-loss warming amplification mechanism. The calculated GMSTs by the parameter-free quantum-physics warming model of halogenated greenhouse gases (GHGs) show excellent agreement with the observed GMSTs after the natural El Niño southern oscillation and volcanic effects are removed. These results have provided strong evidence for the dominant warming mechanism of anthropogenic halogenated GHGs. The results also call for closer scrutiny of the assumptions made in current climate models.