3. 'Hand of God' conjecture: Ozone dispels epidemic?
SARS raged from the winter of 2002 to the spring of 2003, causing extreme panic in society. However, it suddenly disappeared around May and June, leaving various speculations behind. Coincidentally, most of the airborne viruses, such as the influenza virus, erupt in the autumn and the winter and disappear in the spring and the summer. It seems that there is an invisible "hand of God" driving away the epidemic and saving people.
Most researchers looked for correlations between viruses and temperature/humidity. Taking influenza virus as an example, it is generally believed that the virus can maintain its activity for a long time under the condition of low temperature and humidity, and that its activity will be inhibited as the temperature and humidity increase. However, experiments have shown that everyday temperature changes actually do not affect the virus much, but increasing humidity can effectively increase its death rate.
A hypothesis gradually emerged from the discussion with Zhang Yue: perhaps ozone with germicidal and disinfectant ability is the real "hand of God"?
The ozone concentration changes significantly with the seasons: low in autumn and winter and high in spring and summer. According to observations of the ozone layer by Japan Meteorological Agency, the total amount of ozone for Sapporo, Tsukuba, Kagoshima and Naha – Japanese localities from north to south, generally reaches a peak in February to May, but the peak in the farther north comes earlier and that in the farther south comes later.
The ozone concentration varies from region to region as well. The above observations also show a higher peak concentration in the northern regions and a lower peak concentration in the southern regions. Studies have observed that the total amount of ozone in the earth's atmosphere changes significantly with latitude: lowest in equatorial regions and highest in northern regions near latitude 60°.
Theoretically, the stronger the ultraviolet rays, the faster the oxygen molecules disassociate. The equatorial regions, where the sun shines the most, are the most prone to producing ozone. However, many factors and complex mechanisms act on ozone concentration. The stronger the ultraviolet rays, the easier it is to either produce ozone or break it down. The rate of ozone disassociation is also related to temperature: the higher the temperature, the faster the disassociation. Earth-scale atmospheric circulation is also one of the factors that cannot be ignored, because it can transport the ozone generated locally to other regions.
The largest source of tropospheric ozone is the ozone layer in the stratosphere. The oxygen produced by plants through photosynthesis and the NOx and VOC emitted out of industrial activities also affect the concentration of tropospheric ozone.
In short, the ozone concentration, which depends on the magical disassociation and polymerization of oxygen molecules and oxygen atoms, shows a pattern of low in autumn and winter and high in spring and summer. Moreover, the higher the temperature, the faster ozone molecules break down. Humidity also matters, and the germicidal ability of ozone would decrease sharply in the dry state. Therefore, here comes the bold conjecture: when the seasons change and the weather turns warmer, the ozone concentration and air humidity would rise, and the "hand of God" would begin to dispel epidemics.
The more rigorous rationale should be that assisted by temperature and humidity, the main force – ozone drives away epidemics as its concentration rises with the seasons. Of course, ultraviolet rays, another killer of microbes, also kills outdoor bacteria and viruses.
If the conjecture is true and ozone is the "hand of God", then the epidemic caused by novel coronavirus, like SARS and flu, should vanish as ozone levels rise over the seasons, which can be a prospect offering a ray of hope for those suffering from the outbreak.
Certainly, the bold conjecture requires careful verification, and suggestions from different perspectives are more than welcome.
