Ahmed A. HADY Astronomy Department Cairo University Egypt Deep Solar Minimum of Cycle23 and its Impact and its Impact
- -Deep Solar Minimum of cycle Solar cycle 24 predictions and prediction conditions. -The Impact of the deep minimum. -Sun and Heliosphere under quiet and active solar conditions. - Conclusions
Due to the very deep minimum of solar cycle 23, which resulting is the quietest Sun that we have ever seen in almost a century, then the study of the impact and consequences of this deep minimum on the Heliospheric Physics will be the main central subject in this paper
The downtrend line of the Cycle 23, in tilt angle from the peak in 2000 is broken
Solar Maximum and Minimum of cycle 23
Monthly and Yearly Mean SUNSPOT NUMBERS of Cycle Year 2001: Monthly mean: Yearly Means: Year 2003: Monthly mean: Yearly Means: Year 2006: Monthly mean: Yearly Means: Year 2007: Monthly mean: Yearly Means: 7.5 Spotless Days 149 of 365 days ( 41% spotless days) Year 2008: Monthly mean : Yearly Means: 2.85 Spotless Days 266 of 366 days ( 73% spotless days) Year 2009: Monthly mean: Yearly Means: 3.1 Spotless Days 274 of 365 days (75% spotless days)
Monthly and Yearly mean of Flare Index of Solar full disk of Cycle 23 Year 2001, Yearly Mean = 6.80 Monthly Mean: Year 2003, Yearly Mean = 3.46 Monthly mean: Year 2006, Yearly Mean = 0.54 Monthly mean: Year 2007, Yearly Mean = 0.47 Monthly Mean: Year 2008, Yearly Mean = 0.03 Monthly Mean: Year 2009, yearly Mean= Monthly Mean: Data From: Kandilli Observatory
Spotless days percentage, during last century. Only 11 years, 3 of them during cycle23: 2009 Spotless Days (274 of 365 days, 75% spotless days) 2008 Spotless Days (266 of 366 days, 73% spotless days) 2007 Spotless Days (171 of 365 days, 47% spotless days) Typical solar minimum of Cycle 23: 711 spotless days. Typical solar minimum of Cycle 23: 711 spotless days. We’re experiencing a very deep solar minimum, during the last century We’re experiencing a very deep solar minimum, during the last century
DAILY SOLAR DATA: Most eruptive days during Minimum phase of Cycle23 And starting days of Cycle 24
The Solar activity during Decline phase of Cycle 23. Puzzle, like its minimum. still Puzzle, like its minimum. 8-active region appeared during Halloween storm, October Region 0486 produced the two most important solar flares from 1976 until now
Active Region Behavior Region 486 behavior from 2003/10/22 to 2003/11/03 before the region rotate behind western limb Decline of CYCLE 23
Movies of regions SoHo EIT X-Ray Flare (X28/3B) Nov 4, 2003
Solar disk before the region rotate behind the western Limb UT 19:29 on November 4, 2003, and X-28 flare during that time. AR486 Before rotation
Example of solar Storms SoHo EIT X-Ray Flare (X 17.2/4B ) 28 October 2003
Predictions of Cycle 24 Predicting the behavior of a sunspot cycle is fairly reliable once the cycle is well underway. The techniques are used to predict the amplitude of a cycle during the time near and before sunspot minimum, the level of activity at sunspot minimum, and the size of the previous cycles. There are 3 methods for solar cycles predictions based on patterns: 1-The First method depend on that the value of the geomagnetic aa index at its minimum was related to the sunspot number during the ensuing maximum.(by Ohl and Ohl, 1979) 2- Second method is due to a process suggested by Joan Feynman. She separates the geomagnetic aa index into two components: one in phase with and proportional to the sunspot number, the other component is then the remaining signal. 3-Third method is due to Richard Thompson [Solar Physics 148, 383 (1993)]. He found a relationship between the number of days during a sunspot cycle in which the geomagnetic field was "disturbed" and the amplitude of the next sunspot maximum. His method has the advantage of giving a prediction for the size of the next sunspot maximum well before sunspot minimum.
Solar cycle sunspot number: (monthly value = daily average of that month)
MINIMA AND MAXIMA OF SUNSPOT NUMBER CYCLES ===================================================================================== Sunspot Year Smallest Year Largest Rise Fall Cycle Cycle of Smoothed of Smoothed to Max to Min Length Number Min* Monthly Mean** Max* Monthly Mean** (Yrs) (Yrs) (Yrs) *** *** My Estimation of cycle o Mean Cycle Values:
This era Like another parallel with the Maunder Minimum
The Maunder Minimum was not completely devoid of sunspots, as shown by this graph using data from SIDC
This era Like another parallel with the Maunder Minimum There is approximately a 60 year delay between sunspot levels and radiocarbon changes
The great uncertainty tell us: No one fully understands the underlying physics of the sunspot cycle
Solar forcing 1850–2050 used in a NASA GISS climate model. Recent variation pattern used after 2000 Variations in total solar irradiance (TSI) were found to be the most likely cause of significant climate change prior to the industrial era by a U.S. National Academy of Sciences study
Solar activities have had notable effect on palaeoclimatic changes. Contemporary solar activities are so weak and hence expected to cause global cooling. Prevalent global warming, caused by building-up of green-house gases in the atmosphere, seems to exceed this solar effect.
Variations in total solar irradiance (TSI) were found to be the most likely cause of significant climate change prior to the industrial era (by a U.S. National Academy of Sciences study)
The C14 Measurement during the last 1000 years, and climate changes
Reconstruction of solar activity over 11,400 years. Period of equally high activity over 8,000 years ago marked
1-Solar Cycle 23 until now has the Deepest Solar Minimum during the last 100 years 2- Failure of all Predictions of the behavior of a sunspot cycle Number 23. Failure of all early Predictions of the behavior of a sunspot cycle Number 24 during years 2007, 2008 and The great uncertainty stems from one simple fact: No one fully understands the underlying physics of the sunspot cycle. Modern technology cannot, predict the Behavior of sunspot cycle. 3- The length of cycles 20, 21, 22, 23 and its amplitudes are like that the first 4 cycles of the maunder minimum. 4-There are a good correlation between the Solar activity changes, and the global Palaeoclimate changes Contemporary solar activities are so weak and hence are expected to cause global cooling. Prevalent global warming, caused by building-up of green- house gases in the atmosphere, seems to exceed this solar effect.