The day after solar cycle 23

IHY 2009 September 23, 2009

Yu Yi 1 and Su Yeon Oh 2

1 Dept. of Astronomy & Space Science, Chungnam National University, Korea2 Bartol Research Institute, Dept. of Physics & Astronomy, University of Delaware

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 only observations 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 time of 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 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)

Data Period Reference

SPMF 1976- Stanford Solar Observatoryhttp://wso.stanford.edu

SMMF 1975-

IMF 1974-1997 (IMP-8)

Hourly data (National Space Science Data Center)http://nssdcftp.gsfc.nasa.gov/spacecraft_data/

1998-(ACE)

Daily data (ACE Science Center)Level 2 data; http://www.srl.caltech.edu/ACE/ASC/level2/index.html

SSN 1974- Monthly & Yearly (Solar Data Services of National Geophysical Data Center)http://www.ngdc.noaa.gov/stp/SOLAR/ftpsunspotnumber.html

10.7cmRadio flux

1974- Monthly & Yearly (Solar Data Services of National Geophysical Data Center)http://www.ngdc.noaa.gov/stp/SOLAR/FLUX/flux.html

TSI 1978- Daily composite total solar irradiance(Physikalishch-Meteorologisches Observatorium Davos World Radiation Center)http://www.pmodwrc.ch/pmod.php?topic=tsi/composite/SolarConstant

Ap index 1974- Monthly & Yearly (Geomagnetic Data of National Geophysical Data Center)ftp://ftp.ngdc.noaa.gov/STP/GEOMAGNETIC_DATA/INDICES/KP_AP

X-ray Flare 1975- M & X-class (GOES)http://www.ngdc.noaa.gov/stp/SOLAR/ftpsolarflares.html

CR intensity 1974- Monthly & Yearly (McMurdo: Antarctica, 77.9 S, 166.6 E, 48 m altitude).Bartol Research Institute (http://neutronm.bartol.udel.edu/)

II. DATA

Strangeness of solar minimum of solar cycle 23/24

Spotless Sun>> The spotless days 723 days (up to Sep. 22, 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.

Details of SIG parameters in 21-23 solar cycles

Maximum Sunspot Magnetic Field Strength

Abnormality of SIG parameters norm = ( max - min ) / 2 & mean = (max + min ) / 2 abnormality = (P (2008 or 2009) – mean ) / norm [%]

Climate change in 21st century

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.

III. ConclusionsThe 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 - 2Prediction (currently, not a science)• On Aug. 2009, the length of solar cycle 23

becomes 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 : man-made dirty air & aerosols due to fossil fuel • Global Warming in 1990s : man-made CO2 due to fossil fuel• Warming in 21st century : natural forcing by solar activities

Conclusions - 3

In UN politics : • Establish the “International Climate Research

Institute” out of political governance on science, where all the related data should be in public

domain.