Solar Corona?

A colleague pointed out to me yesterday that  evidence is emerging of a four-month periodicity in the number of Covid-19 cases worldwide:

The above graph shows a smoothed version of the data. The raw data also show a clear 7-day periodicity owing to the fact that reporting is reduced at weekends:

I’ll leave it as an exercise for the student to perform a Fourier-transform of the data to demonstrate these effects more convincingly.

Said colleague also pointed out this paper which has the title New indications of the 4-month oscillation in solar activity, atmospheric circulation and Earth’s rotation and the abstract:

The 4-month oscillation, detected earlier by the same authors in geophysical and solar data series, is now confirmed by the analysis of other observations. In the present results the 4-month oscillation is better emphasized than in previous results, and the analysis of the new series confirms that the solar activity contribution to the global atmospheric circulation and consequently to the Earth’s rotation is not negligeable. It is shown that in the effective atmospheric angular momentum and Earth’s rotation, its amplitude is slightly above the amplitude of the oscillation known as the Madden-Julian cycle.

I wonder if these could, by any chance, be related?

P.S. Before I get thrown into social media prison let me make it clear that I am not proposing this as a serious theory!

5 Responses to “Solar Corona?”

  1. Surely another possibility is that people’s behaviour is linked to figures for Covid cases – high case numbers lead to increased adherence to safety protocols, which leads to fewer cases, which leads to complacency about safety protocols, which leads to high case numbers … It’s much like the insurance cycle, where low incidence of claims make insurers more ready to take risks when approving insurance, which leads to more claims, which leads to an insurance crisis, which makes insurers more cautious … (usually over a 10-year-or-so period).

    • telescoper Says:

      That doesn’t really work because the periodicity is much less evident in data from individual countries. There is no consistent global policy so I don’t see how the worldwide data can be explained like that.

  2. It could be the seasonal difference between the northern and southern hemisphere: respiratory viruses are more prevalent in areas with high humidity and low temperature.
    If the data can be separated into hemispheres, it could be checked if it is true.
    If it is possible to find a diffusion law, then the protection could be modulated according to the time of year; even with a known the reason of the global periodicity (the differential equation), different protection could be required near the forecasted diffusion peak.

  3. Length of a school term

  4. Anton Garrett Says:

    Immunity period after catching it?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: