The absence of any major volcanic eruptions post-2000 raises some serious questions regarding the results of this study. One simply cannot look only at one ‘part” or factor (e.g. particles) at a time in atmospheric chemistry and physics and expect the results to represent the “whole.”
Gödel’s incompleteness theorems suggest that no matter how much climate mathematical modeling one does of the parts, it cannot reproduce the “whole.” The “whole” is always much more than what the sum of the “parts” suggest. And in this case the global climate is much, much more than what any mathematical modeling of any part of it (e.g. volcanic particles) suggest, and always will be. Observational science gives us an indication of the physical state of the “whole.” Mathematical modeling cannot do this. And this is why observational science should be preferred and supplemented with modeling rather than the other way around (where modeling is primarily considered).
Lastly, I am always bewildered when I see a paper (or in this case a letter) loaded with coauthors (or signatories), in this case 16. It leaves me with the impression of scientific bullying – the paper with the most coauthors must be the correct one (or perhaps just the politically correct one). But the number of coauthors is irrelevant to the validity of the analysis and likely says more about “group think” dynamics than anything to do with the science itself.
D.A Ridley, S. Solomon, J. E. Barnes, V.D. Burlakov, T. Deshler, S.I. Dolgii, T. Nagai, R.R. Neely III, A.V. Nevzorov, C. Ritter, T. Sakai, B.D. Santer, M. Sato, A. Schmidt, O. Uchino and J. P. Vernier. Total volcanic stratospheric aerosol optical depths and implications for global climate change. Geophysical Research Letters. DOI: 10.1002/2014GL061541
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Turbidity and suspended solids can provide protection of microorganisms against disinfectants and environmental stress. This study suggests hardness plays a role although the experimental conditions were limited.
[Effects of algae and kaolinite particles on the survival of bacteriophage MS2]
He Q, Wu QQ, Ma HF, Zhou ZM, Yuan BL. [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui “Huan jing ke xue” bian ji wei yuan hui.].” Huan Jing Ke Xue. 2014 Aug;35(8):3192-7. Article in Chinese.
In this study, Bacteriophage MS2, Kaolinite and Microcystis aeruginosa were selected as model materials for human enteric viruses, inorganic and organic particles, respectively. The influence of the inorganic (Kaolinite) or organic (Microcystis aeruginosa) particles on the survival of MS2 at different conditions, such as particles concentration, pH, ion concentration and natural organic matter (NOM) were studied. The results showed that Kaolinite had no effect on the survival of phage MS2 except that apparent survival of MS2 increased 1 logarithm in higher hardness water. Microcystis aeruginosa addition reduced 1 logarithm of MS2 survival. However, when the pH value was greater than 4.0 or the concentration of Microcystis aeruginosa was less than 1.0 x 10(6) cells x L(-1), Microcystis aeruginosa addition had no influence on the survival of MS2. In higher hardness water, Microcystis aeruginosa protected MS2 viruses and then increased the survival of MS2. In drinking water, resource containing higher concentration of particles, the survival ability of virus would be enhanced with the increase of the hardness and then elevated the risks of drinking water safety.
Petrovič A, Simonič M. Effect of Chlorella sorokiniana on the biological denitrification of drinking water. Environmental science and pollution research international. 2014 Oct 28.
The influence of Chlorella sorokiniana on drinking water’s biological denitrification was studied at two different initial nitrate concentrations, 50 and 100 mg/L, respectively. Sucrose and grape juice were used as carbon sources. The experiments showed that the denitrification process in the presence of algae was, even at low concentrations, i.e. 50 mg/L of nitrate, slower than without them, but yet still more than 95 % of nitrate was removed in 24 h. It was also discovered that, with the addition of ammonium and urea, the urea interfered much more with the denitrification process, as less than 50 % of the initial nitrate was removed. However, algae did not contribute to the nitrate and ammonium removals, as the final concentrations of both in the presence of algae were higher by approx 5 %. At 100 mg/L of initial nitrate, the denitrification kinetics in the presence of algae was apparently slower regarding those experiments at lower levels of nitrate and only 65-70 % of nitrate was removed over 24 h. Using grape juice instead of sucrose improved the nitrate removal slightly.
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