Sunspots

The combination image below, adapted from NOAA and from an earlier post, shows the observed values for the number of sunspots (top) and for the F10.7cm radio flux (bottom) for cycle 25, up to May 2022, as well as the values predicted by NOAA.


Within a few years time, sunspots are expected to reach the peak of the current solar cycle (number 25). As above image shows, NOAA predicts the maximum for cycle 25 to be reached in July 2025, when NOAA predicts the number of sunspots to be 115.3 and radio flux to be 135.8. However, as the above image also shows, observed values for May 2022 are already very close to the maximum values predicted by NOAA to be reached in July 2025. 

Green dot: NOAA/NASA amplitude prediction. Purple dot: study's amplitude prediction

These high observations appear to confirm the findings of a 2020 study by Scott McIntosh et al. that, due to interactions with earlier cycles, sunspot Solar Cycle 25 could have a magnitude that rivals the top few since records began (see above image, from the study). 



According to above image, from IPCC AR4 SPM, solar irradiance corresponds with a radiative forcing of 0.12 W/m², with a range of 0.06 to 0.3 W/m².

According to James Hansen et al., the variation in forcing is as much as 0.25 W/m⁻² (from solar minimum to solar maximum). The image below, by James Hansen et al. (updated September 1, 2022), shows that the rise in sunspots forcing from May 2020 to July 2025 could make a difference of about 0.2 W/m² (which translates into some 0.15°C or 0.27°F). 


The image at the top shows that the current sunspots cycle up to May 2022 is stronger than expected. If this trend continues, the rise in sunspots forcing from May 2020 to July 2025 may well make a difference of more than 0.2°C. 

The next El Niño looks set to line up with a high peak in sunspots, in a cataclysmic alignment that could push up the temperature enough to cause dramatic sea ice loss in the Arctic, resulting in runaway temperature rise by 2026, as an earlier post concluded.


Links

• NOAA - Space Weather Prediction Center
https://www.swpc.noaa.gov/products/solar-cycle-progression

• Cataclysmic Alignment
https://arctic-news.blogspot.com/2022/06/cataclysmic-alignment.html

• The Termination Event has Arrived - by Tony Phillips
• Overlapping Magnetic Activity Cycles and the Sunspot Number: Forecasting Sunspot Cycle 25 Amplitude - by Scott McIntosh et al. (2020)

• IPCC - Radiative forcing components - from IPCC AR4 WG1 SPM (2007)

• Young people’s burden: requirement of negative CO2 emissions - by James Hansen et al.
https://esd.copernicus.org/articles/8/577/2017

• Solar Irradiance - by James Hansen et al. 
http://www.columbia.edu/~mhs119/Solar