On the Correlation Between Maximum Amplitude and Smoothed Monthly Mean Sunspot Number During the Rise of the Cycle
Title | On the Correlation Between Maximum Amplitude and Smoothed Monthly Mean Sunspot Number During the Rise of the Cycle PDF eBook |
Author | Robert M. Wilson |
Publisher | |
Pages | 14 |
Release | 1998 |
Genre | Solar cycle |
ISBN |
On the Correlation Between Maximum Amplitude and Smoothed Monthly Mean Sunspot Number During the Rise of the Cycle (from T
Title | On the Correlation Between Maximum Amplitude and Smoothed Monthly Mean Sunspot Number During the Rise of the Cycle (from T PDF eBook |
Author | Robert M. Wilson |
Publisher | |
Pages | 24 |
Release | 1998 |
Genre | Solar cycle |
ISBN |
On Determining the Rise, Size, and Duration Classes of a Sunspot Cycle
Title | On Determining the Rise, Size, and Duration Classes of a Sunspot Cycle PDF eBook |
Author | Robert M. Wilson |
Publisher | |
Pages | 20 |
Release | 1996 |
Genre | Solar cycle |
ISBN |
On the Importance of Cycle Minimum in Sunspot Cycle Prediction
Title | On the Importance of Cycle Minimum in Sunspot Cycle Prediction PDF eBook |
Author | Robert M. Wilson |
Publisher | |
Pages | 20 |
Release | 1996 |
Genre | Solar cycle |
ISBN |
An Estimate of the Size and Shape of Sunspot Cycle 24 Based on Its Early Cycle Behavior Using the Hathaway-Wilson-Reichmann Shape-Fitting Function
Title | An Estimate of the Size and Shape of Sunspot Cycle 24 Based on Its Early Cycle Behavior Using the Hathaway-Wilson-Reichmann Shape-Fitting Function PDF eBook |
Author | National Aeronaut Administration (Nasa) |
Publisher | |
Pages | 36 |
Release | 2020-08-06 |
Genre | |
ISBN |
On the basis of 12-month moving averages (12-mma) of monthly mean sunspot number (R), sunspot cycle 24 had its minimum amplitude (Rm = 1.7) in December 2008. At 12 mo past minimum, R measured 8.3, and at 18 mo past minimum, it measured 16.4. Thus far, the maximum month-to-month rate of rise in 12-mma values of monthly mean sunspot number (AR(t) max) has been 1.7, having occurred at elapsed times past minimum amplitude (t) of 14 and 15 mo. Compared to other sunspot cycles of the modern era, cycle 24's Rm and AR(t) max (as observed so far) are the smallest on record, suggesting that it likely will be a slow-rising, long-period sunspot cycle of below average maximum amplitude (RM). Supporting this view is the now observed relative strength of cycle 24's geomagnetic minimum amplitude as measured using the 12-mma value of the aa-geomagnetic index (aam = 8.4), which also is the smallest on record, having occurred at t equals 8 and 9 mo. From the method of Ohl (the inferred preferential association between RM and aam), one predicts RM = 55 +/- 17 (the ?1 se prediction interval) for cycle 24. Furthermore, from the Waldmeier effect (the inferred preferential association between the ascent duration (ASC) and RM) one predicts an ASC longer than 48 mo for cycle 24; hence, maximum amplitude occurrence should be after December 2012. Application of the Hathaway-Wilson-Reichmann shape-fitting function, using an RM = 70 and ASC = 56 mo, is found to adequately fit the early sunspot number growth of cycle 24. Wilson, Robert M. Marshall Space Flight Center NASA/TP-2011-216461, M-1310 SUNSPOTS; SUNSPOT CYCLE; SHAPE FUNCTIONS; GEOMAGNETISM; ASCENT; FITTING; SHAPES
Gauging the Nearness and Size of Cycle Minimum
Title | Gauging the Nearness and Size of Cycle Minimum PDF eBook |
Author | Robert M. Wilson |
Publisher | |
Pages | 24 |
Release | 1997 |
Genre | Solar cycle |
ISBN |
An Examination of Sunspot Number Rates of Growth and Decay in Relation to the Sunspot Cycle
Title | An Examination of Sunspot Number Rates of Growth and Decay in Relation to the Sunspot Cycle PDF eBook |
Author | National Aeronautics and Space Administration (NASA) |
Publisher | Createspace Independent Publishing Platform |
Pages | 36 |
Release | 2018-05-29 |
Genre | |
ISBN | 9781720379829 |
On the basis of annual sunspot number averages, sunspot number rates of growth and decay are examined relative to both minimum and maximum amplitudes and the time of their occurrences using cycles 12 through present, the most reliably determined sunspot cycles. Indeed, strong correlations are found for predicting the minimum and maximum amplitudes and the time of their occurrences years in advance. As applied to predicting sunspot minimum for cycle 24, the next cycle, its minimum appears likely to occur in 2006, especially if it is a robust cycle similar in nature to cycles 17-23.Wilson, Robert M. and Hathaway, David H.Marshall Space Flight CenterSUNSPOT CYCLE; SUNSPOTS; SUN; DECAY RATES; AMPLITUDES; CORRELATION; TIME; ASCENT; STANDARD DEVIATION