We may be witnessing the sun’s last dying gasps before entering into a long slumber. The impact of that slumber on Earth’s climate remains the subject of growing scientific speculation.
Its been known for years that sunspot umbral magnetic field strength has been declining while their intensity has been rising, thanks to researchers Matt Penn and Bill Livingston at the National Solar Observatory.
The changes are independent of the 11-year sunspot cycle.
A steady decline in umbral magnetic field strength is the most dramatic evidence that sunspots are fading away. Should their field strength drop below 1,500 gauss it becomes physically impossible for sunspots to form and they will disappear.
Less sunspot activity reduces the sun’s radiant energy output and cools Earth.
Several trends in sunspot activity for this cycle are becoming clear.
First, northern sunspot activity is near its end while southern activity is at its zenith. The only drama left is when will southern spot polarity reversal occur. That is expected any time. The sun right now is a magnetic monopole. The sun will finish its inexorable journey to sunspot minimum after southern sunspot polarity reversal occurs.
The decline in sunspot magnetic field strength is continuing, but showing signs of leveling off along a shallow concave curve. Umbral intensity is showing a similar change in the reverse.
Sunspots may not disappear completely, but they will be so weak that a long term decrease in solar wind and a slight but prolonged decrease in the sun’s temperature will result.
The latest solar data from this month reinforces the belief that our sun is headed into a long-term period of low solar activity.
As time goes on a link between decreasing solar activity and the halt in global warming 17 years ago becomes harder and harder to deny.