1. Solar Variation and Climate
Hunter Clasen
4/26/11
EAS 4480

2. Introduction
Does the 11-year sunspot cycle control variation in solar flux?
Is there a correlation between solar flux and SST?
Three time series ( )
Sunspots
Solar Flux
GMSST (global mean sea surface temperature)

3. Periodogram: Sunspots
Periodogram: Solar Flux
Coherence: Sunspots and Solar Flux
Correlation Coefficient:
P =
(Both time series are detrended)

4. Solar Flux and GMSST Correlation Coefficient: -0.0080 P = 0.9832

5. CPSD: Solar Flux and GMSST

6. Phase Spectrum
Lag = 15
τ = 11 years
∆t = .5 years

7. Coherence

8. Lomb-scargle: Solar Flux
Power
Frequency (Hz)

9. Lomb-scargle: GMSST
Power
Frequency (Hz)

10. Solar Flux and GMSST
detrended yearly averages used instead of monthly data
GMSST smoothed with 3 year running mean
Is r significant?
Correlation Coefficient: P =
Correlation Coefficient ( ): P =

11. Coherence: Solar Flux and GMSST

12. Conclusion
The variation in solar flux is strongly correlated with the sunspot cycle
Solar flux has a strong effect on SST
SST is also affected by other processes:
Greenhouse effect
Ocean circulation

13. Sources NOAA Earth System Research Laboratory
MATLAB sunspot data