Solar Physics

1
What Happens if Sea Level Rises 100m (330)
2
Solar Physics Climate
3
(No Transcript)
4
(No Transcript)
5
(No Transcript)
6
(No Transcript)
7
MAUNDER MINIMUM CLIMATE
8
AMP 0.1
SOLAR IRRADIANCE VS TIME OVER TWO DECADES
9
(No Transcript)
10
(No Transcript)
11
RESPONSE TO SOLAR FORCING WITH PERIOD 10 YEARS
(Stevens EBCM)
12
Optimal detection of the temperature of a bath
Suppose we have 2 thermometers that make
estimates of the temp.
The error variances are
We want to make an estimate of the true
temperature, Ttrue
What are the optimal weights,
?
13
A little algebra
Now differentiate wrt
and set the result to zero
Obtain
After some manipulation
Moral The weighting is inversely proportional
to the error variance for each gauge.
And it generalized to N gauges!
14
Technique Assumptions

• Linear Superpostion
• Tdata(t) SsasSs(t)N(t) sG, A, V, S
• EOF Expansion of all Fields
• e.g., T(t) Sn Tn EOFn(t), Tn statistically
  independent
• CycloStationary EOFs along Time Axis
• m(t)m(th) Cov (t, t)Cov(th, th)

NEW to this STUDY
15
EOF SUMMARY
16
Attempting to Improve Detection by Including
Seasons

1. Sun is more overhead in local summer
2. Natural variability is less in local summer
3. Land mass in NH should dominate global average
4. Performance for aerosol should improve
5. Performance for Solar 11yr cycle should improve

First step use global average time series
17
WHY INCLUDE SEASONS?
Variance
Variance
SEASONAL CYCLE OF Natural Variability Aerosol
Forcing
Amplitude
JAN DEC
18
ANALYSIS OF MODAL CONTRIBUTIONS
FRACTION OF SIGNAL2 CAPTURED BY
TRUNCATED EXPANSION
SEASONS RETAINED
ANNUAL ONLY
(a measure of goodness of fit for the signal
representation)
NUMBER OF EOF MODES RETAINED -gt
19
ANALYSIS OF EOF MODAL CONTRIBUTIONS, CONTINUED
GREENHOUSE GAS SIGNAL (G)
IMPROVEMENT DUE TO SEASONAL
SNR2
LESSONS

1. ESTIMATE STABILIZES
2. SEASONS IMPROVE SNR

AMPLITUDE OF G (ESTIMATE)
EOF MODES RETAINED --gt.
20
Volcanic
Solar
A
G
SIGNAL2
Frac Sig2 captured
RESULTS from 101 yr Set
EOF Eig. Val.
EIGENVALUE
snr from Indiv EOF
INDIVIDUAL MODE SNR2
CUMULATIVE
SNR2
?G
Amp Est.
?A
modes retained
21
S
V
VOLCANIC AND SOLAR SIGNALS
snrgt2
22
Solar Cycle SNR2 and Amplitude Estimate
seasonal
annual
DETECTION!
23
Monte Carlo Study with 200 50 Year
Simulations Illustrating the Correlation between
Estimates of G and A. Dashed 95 CI for Annual
data, Solid Seasonal
Est. of A
NOTE The Diagram for Solar is Circular (not
shown)
Est. of G
24
LAST 50 YRS
LAST 100 YRS
95 CONFIDENCE REGIONS FOR S vs G, A, V
25
OPTIMAL FIT TO OBSERVATIONAL DATA
26
DETECTION CONCLUSIONSQigang Wu G. North
(Unpublished, 2004)

• G, A,V, S are All Significant at 5 Level
• G, A,V are All Slightly Smaller than Expected
• S is Now Detected at 95 Level of Confidence and
  is Useful as a Test of CMs
• Including Seasons Improves Performance

Could we use climate signal detection to test the
sunspot-L relation?