While it is not unexpected that experts predicting how active Solar Cycle (SC) 25 will be 
compared to SC 24, the new forecast from NASA is significantly different than the National Weather Service forecast.
A few weeks ago, I reported that the National Weather Service forecast for SC 25 activity would be slightly greater than SC 24. They added:
“The expectation that Cycle 25 will be comparable in size to Cycle 24 means that the steady decline in solar cycle amplitude, seen from cycles 21-24, has come to an end and that there is no indication that we are currently approaching a Maunder-type minimum in solar activity.”
NASA’s prediction is different, really different. Their expert says:
Research now underway may have found a reliable new method to predict this solar activity. The Sun’s activity rises and falls in an 11-year cycle. The forecast for the next solar cycle says it will be the weakest of the last 200 years. The maximum of this next cycle – measured in terms of sunspot number, a standard measure of solar activity level – could be 30 to 50% lower than the most recent one. The results show that the next cycle will start in 2020 and reach its maximum in 2025.
The NASA prediction did not discuss the possibility of a Maunder minimum. However their prediction does not rule out a Maunder minimum in progress as it forecasts SC25 will not be the end of a steady decline in solar cycle amplitude.
Both of the predicting groups acknowledge that they are still far from a full understanding of how the Sun works. So, we will just have to wait and see.
cbdakota
Climate Change Sanity 
is there evidence that our surface temperature is responsive to the solar cycle?
Chaamjamal
I think it is generally believed that low solar activity during the years from 1645 to 1715 resulted in the Maunder Minimum. The Maunder Minimum was a period of cooling. The instrumentation for measuring magnetic fields did not exist then, but sunspot counting was done then. Sunspot activity is a good proxy for solar activity. Lots of sunspots indicate a very activity Sun and few sunspots indicate low activity. Later on there was another minimum,the Dalton Minimum that occurred around the early 1800’s. Surface temperatures did go down. Then the Grand Solar Maximum took place from abut 1950 to 2009. Surface temperatures have risen. So far, it has taken a consecutive number of very active solar cycle to be able to detect a rising temperature or a consecutive number of low activity solar cycles to be able to detect a cooling of the surface temperature.
This proposition is somewhat contentious. Emperical data suggests that it is true. Volcano activity is often said to have caused the minimums. One knows that volcanic activity can cause cooling. But “why” one has to ask “are those volcanos happening when the Sun’s activity is low?”
cbdakota
Thank you very much for this very informed comment. I have been a solar cycle skeptic because i could not find a correlation at an annual time scale. But john casey set me straight. He says we need longer time scales and suggested 11 years and 22 years. I did that work and he is right. There is a clear relationship that suggests that surface temperature is responsive to the solar cycle. Please see my post “sunspots and temperature”
Here is the link to Sunspots and Temperature:
https://tambonthongchai.com/2019/06/19/sunspots/
Very nice work! I shall keep this for reference.
cbdakota
Thank you
How can a lower solar activity leads to global warming? Is there something wrong in Svenmarks theory? And if so, what?
Raymond, sorry to take so long to reply but domestic issues take first place. And today was a break for me in that I got to play a round of golf.
Well I do not think the Svensmark theory is wrong in that he says lower solar activity invites more cosmic rays into our atmosphere and those cosmic rays do strike oxygen molecules, for example, and shatter them. The pieces are sites upon which clouds can form. Low clouds increase the albedo thus reducing the Sun’s radiation that strikes the surface. Cooling happens. CERN provided two conclusions when they tested Svensmarks theory. First they said that cosmic rays do as Svensmark says but collisions do not form enough particles to make a significant impact on cloud formation. CERN then injected normal atmosphere containing dust particles, pollen, etc. This was followed by bombarding the test gas and found that enough particles were formed that would be enough to make a significant impact on cloud formation. That an increase of cosmic rays correlates with lower Solar activity has clearly been established.
cbdakota