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The Unprecedented Solar Magnetic Fields and Their Implications December 21, 2009 Yu Yi Dept. of Astronomy & Space Science, Chungnam National University. I. Introduction. Many solar, interplanetary and geomagnetic (SIG) activity parameters show a 11-year cycle
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The Unprecedented Solar Magnetic Fields and Their Implications December 21, 2009 Yu Yi Dept. of Astronomy & Space Science, Chungnam National University
I. Introduction • Many solar, interplanetary and geomagnetic (SIG) activity parameters show a 11-year cycle in sync with Solar Sunspot Number (SSN). • The SSN of about 400 year record is the key parameter in producing the proxy data of parameters with observations only since 1970’s. • In history, the cooling times of Maunder and Dalton Minima are correlated with the low SSN activities.
The US Solar Cycle 24 Prediction Panel has renounced their consensus-based official(?) onset timeof solar cycle 24 two times already : Mar. 2007 (announced on Oct. 2006) =>> Mar. 2008 ( revised on Apr. 2007) =>> Dec. 2008 (revised on May 2009) =>> ? (to be revised one more time) • However, the SIG parameters are still updating the record of unprecedented values. >>> Q: When is the solar activity minimum of solar cycle 23/24 ?
Up to date, only one model of solar forcing on climate (Svensmark & Friis-Christensen, 1997) : weaker IMF >> increased CR flux >> more cloud >> albedo increased >> cooling • However, the cooling and warming patterns different in locations on the globe should be explained. >>> Q: What were SIG activity levels during Dalton and Maunder Minima ? >>> Q: What is the mechanism of solar cooling of the Earth in natural forcing?
Solar Magnetic Fields • Solar Polar Magnetic Field (SPMF) The average magnetic field of the polar region over latitude 55 deg. measured by Wilcox Stanford Solar Observatory (Scherrer et al. 1977a; Svalgaard, 1978) • Solar Mean Magnetic Field (SMMF) The Sun-as-a-star mean magnetic field of full disk (Scherrer et al. 1977b)
Abnormality of SIG parameters norm = ( max - min ) / 2 & mean = (max + min ) / 2 abnormality = (P (2008 or 2009) – mean ) / norm [%]
Spotless Sun>> The spotless days 743 days (up to Oct. 23, 2009) in current solar minimum of solar cycle 23/24 are the longest in record. >> The monthly mean SSN of Aug. 2009 was absolute zero.
Cold times followed after the a pair of solar cycles whose lengths had gotten shorter under 10 years and then longer over 13 years , e.g. Dalton Minimum (SC 4, 5 & 6) & Maunder minimum (before SC numbered). ==> SC 23, 24 & 25 might be colder ! cf) Krivova, Solanki & Beer (2002)
SC 3 SC 4 SC 5
HadCRUT3 is a global mean near-surface temperature. Has it turned into cooling or temporary stagnation ?
WASHINGTON (AFP) – The Arctic sea ice pack thawed to its third smallest size on record during the of 2009 since 1979, US government scientists said. => However, does it look growing?
III. Conclusions The SIG data tell us • Most of SIG activity parameters are still renewing the unprecedented records in 2009. • Highly abnormal parameters are SPMF & IMF. In heliophysical and solar physics : • IMF might be much weaker (~3 nT) during the Dalton and Maunder Minima than previously expected (~6 nT) in proxy calculation. • Suggested research topic: How IMF magnitude variation changes the climate?
Conclusions - 2 Prediction (currently, not a science) • On Aug. 2009, the length of solar cycle 23 got longer than 13.25 years. • Cooling period may come like Dalton Minimum or Maunder Minimum in worse case in natural forcing though. History of climate change scenarios • Global Cooling in 1970s (by meteorologists): man-made dirty air & aerosols due to fossil fuel • Global Warming in 1990s (by meteorologists): man-made CO2 due to fossil fuel • Cooling in 21st century (by solar physicists): natural forcing by solar activities
Conclusions- 3 • Eco-friendly Green Life cultured by the Korean: Save the planet: eat a dog? In Carbon Footprint measure, 1 pet dog = 2 x 4.6 litre Land Cruiser driven 10,000 km a year Victoria University, New Zealand (The Dominion Post)