Global surface temperatures have been falling steadily since the last El Nino, glacier melt has been decelerating rapidly and Arctic sea ice has been making a surprising recovery this year. Moreover, the equatorial Pacific has just entered a global cooling La Nina phase.
But there is another far more ominous, long-term sign that the planet is cooling. Prof. Fritz Vahrenholt and Frank Bosse write: Signs show the Earth is heading into a new Dalton Minimum — like the one the planet was forced to endure some 200 years ago.
By Frank Bosse und Fritz Vahrenholt
(Translated/edited by P Gosselin)
The (almost) sole provider of the Earth’s energy at the center of our solar system was once again well below normal in activity last month. The measured sunspot number (SSN) was on average only 13.2. Especially during the middle October trimester (from October 9 to October 20) the sun was almost spotless (11 of 12 days). Thus our sun saw a level of activity that was just 33% of what is normal for this month (no. 107) into the solar cycle.
Looking at the entire solar cycle, the current cycle is only 56% as active as the mean solar cycle (shown in blue below), which is calculated from the previous 23 solar cycles:
Figure 1: The current cycle is shown by the red curve and is compared to the mean curve (blue) and the similar solar cycle number 5 (black). Over the past year we observe that there has been a hiatus in solar activity with a mean SSN of about 25.
Comparison of all the cycles follows:
Fig. 2: The accumulated sunspot anomaly from the mean of the previous 23 cycles – 107 months into the cycle.
The current solar cycle 24 is the third weakest since the systematic observation of solar cycle activity began in 1755. Only solar cycles nos. 5 and 6 (1798…1823 during the Dalton Minimum) were weaker.
Now we would like to look into the future to solar cycle number 25, which is expected to begin around 2021. To do this we use the strength of the current polar field, which we reported on in greater detail in December 2016, also read here in English.
Entering a phase similar to the Dalton Minimum
The researchers at the Wilcox-Observatory of Stanford University were alerted to a impaired mirror that caused inaccurate readings. Since then the error has been resolved and we can now take another look at the data. The fields (the average of the northern and southern hemisphere values) were at 57 centi-Gauss (cG).
The previous solar cycle 23 (an indicator for sunspot activity for the current cycle) at the same point in time in the cycle was approx. 61 cG. In comparison: the quite normal solar cycle 23 (see Fig. .2) was indicated by a field of approx. 104 cG. Thus it is highly probably that also solar cycle 25 will be less active than normal like the current cycle is.
As a result we will experience a weak solar phase that is comparable to that of the Dalton Minimum. It is unlikely that we will experience an even weaker phase like that of the Maunder-Minimum, which occurred between 1650 and 1700.