SOLAR VARIABILITY AND

CLIMATE

HAS THE EARTH WARMED?

Climatic Research Unit, UK

HAS THE EARTH WARMED?

MANKIND - EARTH

CO2

SUN - EARTH

Mathew (5)

SUN - EARTH

The solar open magnetic field, solar wind and energetic particles affect the Earth's magnetosphere and ionosphere

SUN - EARTH

Correlations between solaractivity and climate indicators

Cycle lengthNH temperature

Friis-Christensen &Lassen (1994)

SUN - EARTH

Correlations between solaractivity and climate indicators

H. Avercamp

SUN - EARTH:Possible Mechanisms

Total irradiance variations: energy input into the Earth's atmosphere

UV irradiance variations: changes in stratospheric chemistry

Modulation of cosmic ray flux by solar magnetism: changes in cloud cover

VARIABLE SUN

1996 2000

PASSAGE OF A SUNSPOT GROUP

FLUX TUBES

PASSAGE OF A FACULAR GROUP

3- COMPONENT MODEL

F() - quiet Sun flux (Fontenla et al. 1993)

F() - sunspot flux; separate umbra/penumbra (cool Kurucz models)

F() - facular flux (modified P-model; Fontenla et al. 1993; Unruh et al. 2000)

(t) - filling factor of sunspots (MDI continuum)

(t) - filling factor of faculae (MDI magnetograms)

s

f

FILLING FACTORS

= 1 (or 0) s

f

= 1--q s f

TOTAL FLUX

TSI: 1996 - 2001

Krivova et al. 2002

MODEL VS. OBSERVATIONS

SPECTRAL IRRADIANCE

SECULAR CHANGE:Stellar Evidence

Baliunas & Jastrow 1990

SECULAR CHANGE:Heliospheric Evidence

SECULAR CHANGE:Heliospheric Evidence

1996 2000

SECULAR CHANGE:Heliospheric Evidence

SOLAR VARIABILITYAND CLIMATE

Solanki & Krivova 2002