Penn and Livingston, in their September 2010 IAU publication “Long-Term Evolution Of Sunspot Magnetic Fields” predicted that Solar Cycle 24 would peak at an International Sunspot number of 66 and Solar Cycle 25 at 7!!
Considering that NASA believes that the peak for Cycle 24 will be 67, their prediction looks pretty good. So would you bet against their Cycle 25 prediction of 7?
Posted in AGW, Ap index, Solar Activity, Solar Cycle 24, Solar Cycle 25, Solar Flux, Sun, sun and climate, Sunspots
While the IPCC doesn’t have an answer for why there has been no statistical increase in global temperatures for going on 17 years, they don’t think the Sun has been a significant factor. They generalize that volcanoes, deep ocean warming, and particulate matter in the atmosphere may be the cause.
Copy of Woodcutting by TheGuardian.com by Duncan Clark
Solar Cycle 24’s Sunspot number bounced up a little as did the F10.7cm radio flux. However, Cycle 24 is still on track to be the least active Cycle since the first part of the last century. The Sun’s North pole appears to have firmly switched its polarity but the South Pole may be months away from switching its polarity. A cycle’s “maximum” is usually called when both poles have done the swap.
The August Sunspot and the F10.7cm radio flux are shown below (Click on Charts to enhance view):
Posted in AGW, Global Temperatures, Solar Activity, Solar Cycle 24, Solar Flux, Sun, Sunspots
NASA predicts a solar magnetic field reversal in about 3 to 4 months. When that happens, Solar Cycle 24 will have reached what is known as the cycle maximum. After that the Sunspot numbers will decrease with time. There is a possibility that a short period of none at all will happen before Cycle 25 kicks in. NASA has produced a video that discusses the mechanism and the implications of the solar magnetic field reversal. The video can be viewed by clicking here.
The July charts for Sunspots and F10.7 cm Radio flux are shown below.
Posted in AGW, Ap index, Environment, Global Temperatures, IPCC, Solar Activity, Solar Cycle 24, Solar Cycle 25, Sun, sun and climate, Sunspots
There are several theories for the cause of glacial periods–Cycles of glaciers followed by interglacial warm periods and then repeating that cycle. Of those theories, the Milankovitch Cycles theory seems to have a broad base of adherents who believe it to have the best answer that question. The Milankovitch theory has some weaknesses. So this posting remains skeptical, however, it appears that there are good reasons why it is probably the most accepted theory. That Richard Lindzen is a supporter of the theory is one of the good reasons.
The Milankovitch theory says that moving in and out of glacial periods is a result of variation in the Earth’s orbit and orientation. Three parameters—Earth’s eccentric orbit around the Sun, the planet’s axial tilt and the procession of its axis are the basis of the theory. These parameters are pretty well defined. The coincidence with certain combinations of the three parameters and the paleohistory of glacial periods is reasonably close. A posting by Doug Hoffman on his blog, the Resilient Earth “Confirmed! Orbital Cycles Control Ice Ages” is very good. I could not say it as well, so this posting will lift much from his.
From Hoffman’s posting:
Earth’s orbit goes from measurably elliptical to nearly circular in a cycle that takes around 100,000 years. Presently, Earth is in a period of low eccentricity, about 3%. This causes a seasonal change in solar energy of 7%. The difference between summer and winter is a 7% difference in the energy a hemisphere receives from the Sun. When Earth’s orbital eccentricity is at its peak (~9%), seasonal variation reaches 20-30%. Additionally, a more eccentric orbit will change the length of seasons in each hemisphere by changing the length of time between the vernal and autumnal equinoxes. (Click on the Chart to enlarge.)
Variation in Axial Obliquity, Orbital Eccentricity, and Polar Precession.NOAA.
Solar Cycle 24 activity was low in June. Sunspots took a sizable drop from about 77 in May to 52 in June. Solar flux dropped as well. (Click on charts to enhance clarity.)
The experts believe that Cycle 24 will match Cycle 14. NASA is predicting Cycle 24 Sunspot peak at 67 whereas Cycle 14’s peak was 64. Cycle 14 began February, 1902 and ended August, 1913. Temperatures during that time were much colder than the average since that time. My March 8, 2013 posting has some interesting statistics to make comparisons of Cycle 24 and other Solar Cycles. There is a plot of temperature anomalies from 1880 to 2010 that you can compare to Solar Cycle size. You can access that data by clicking here.
cbdakota
Chart curtsey of Solen.com
Posted in AGW, Ap index, Solar Activity, Solar Cycle 24, Solar Flux, Sun, sun and climate, Sunspots
Posted in AGW, Environment, Global Temperatures, Solar Activity, Solar Cycle 24, Solar Flux, Sun, sun and climate, Sunspots
Climate Change Sanity 