By Frank Bosse and Fritz Vahrenholt
(Translated/edited by P Gosselin)
Our sole relevant source of energy at the center of our solar system was quieter than normal in July for our current solar cycle (SC) 24. The entire cycle so far has only been 56% as active as the mean cycle.
And with a sunspot number (SSN) of 32.5 in July, it was only 42% as active as the mean for the 92nd month into the cycle. Compared to a month earlier (only 27%) it was a slight uptick:
Fig. 1: SC 24 until July 2016 (red) compared to the mean cycle, which is computed from the mean of the previous 23 cycles (blue), and SC5 (black) which was very similar in behavior.
The small upward hook arises from there being 5 spotless days in July, compared to 9 in June. After the record lame start of the cycle over the first 2 years, are we now experiencing a similar end as well?
Compared to the previous cycles, not much has changed since the month earlier:
Fig. 2: Accumulated sunspot anomaly from the mean (blue curve, Figure 1) for each cycle, 92 months into the cycle.
The red bar to the far right has been gaining in length in its downward direction over the past few months. Where will it end? There are still about 36 months remaining in the cycle, and most likely the bar representing SC 24 will continue to fall further. In our next report we will take a look again at the current polar fields, which are the first predictors for the upcoming cycle.
Due to time constraints, NTZ summarizes the main points pertaining to the AMO, the subject of the second part of Vahrenholt’s and Bosse’s post. Vahrenholt and Bosse present a figure that shows that the AMO likely has reached its positive maxima, and now may be headed downwards, which will have an impact on global climate over the coming decades.
AMO since 1950 with annual mean values and 20-year smoothing (low pass: Loess).
Bosse and Vahrenholt write that the AMO has an impact on hurricanes and the temperatures in Western Europe during the summer: “Yes, that’s right. How warm our summers are depends in large part on the AMO.”
The following chart depicts the land surface temperatures of Western Europe:
Western Europe land temperatures (CRUTEM 4) with a 20-year smoothing (Loess).
The two Die kalte Sonne authors write that the AMO plays a role on global temperature and that climate models have not taken the powerful AMO adequately into account, citing recent scientific publications. They summarize:
Many climate models and prognoses were tuned using data from the period 1976 to 2005 and assigned the effects of the reoccurring AMO increase during these years over to CO2. Climate sensitivity, the effect of CO2 on temperature, is thus overstated by 30-50%. The temperature changes expected from CO2 are less.”