Counting Sunspots and Sunspot Inflation

Guest post by Dr. Leif Svalgaard The official sunspot number is issued by SIDC in Brussels . The [relative] sunspot number was introduced by Rudolf Wolf  in the middle of the 19th century. He called it the ‘relative’ number because it is rather like an index instead of the actual number of spots…


The sun – still slumping

The latest solar cycle update graphs have been released by the NOAA SWPC today, and the anemic cycle 24 continues: The current count isn’t keeping up with the prediction line in red. Not only is the sunspot count low, so is the 10.7cm radio flux and the Ap magnetic index:

Solar cycle update: sunspots down, Ap index way down

The NOAA SWPC monthly solar cycle update has been published here, and after a big spike last month, the sunspot count is down again. There’s an even bigger drop though in the Ap geomagnetic index, as seen and discussed below the Continue reading line. 10.7 centimeter radio flux was down slightly too.