Guest post by David Archibald

The heliospheric current sheet has flattened meaning that Solar Cycle 24 is over and we are now in Solar Cycle 25.

https://wattsupwiththat.com/2020/04/22/solar-cycle-25-has-started/

Figure 4: Ap Index 1932 – 2020

What this figure shows is that there has been a permanent shift down in the Sun’s magnetic flux into the New Cold Period. The breakover was most probably in 2005 when the Ap Index suddenly dropped to solar-minimum type levels just above the Modern Warm Period activity floor. Then there was another sudden break down in 2008 with the absolute low in 2009.

Figure 8: Oulu Neutron Count 1964 – 2020

Now that the solar minimum is in, the peak in neutron count should be one year from now. The amplitude of the peak is likely to be close to the amplitude of the 23/24 minimum.

Figure 9: F10.7 flux and Oulu neutron count

As with Figure 5, this figure shows the result of the sudden step down of the Sun’s magnetic activity in 2005. The Sun has entered a new regime of activity with the New Cold Period.