SAM

[pukpr]

Southern Annular Modulation, perhaps with some reanalysis
https://psl.noaa.gov/data/20thC_Rean/timeseries/monthly/SAM/sam.20crv2c.long.data

---- LTE ----
   0.01778251478 :trend:
  -0.01868988433 :K0:
 -35.57075635714 :level:
   4.57660923626,    0.34932666185,    1.85915840429 0
 -31.66259637658,    0.67345642130,   -1.17203363495 0
   0.55892752078,    0.29104596988,   -0.46579923010 0
   4.87018132134,    0.30501167120,   -1.29481850421 0
   0.90257992907,    0.19919720330,   -2.52219585168 0
   1.48036359657,    0.31940231242,   -1.35654818519 0
  -3.88950892698,    0.23384259599,    0.43028724256 0
-457.83338727929,    0.82992241610,   -0.24598772766 0
-1309.93362754001,    0.50144549593,   -1.93744509686 0
2256.38879458934,    0.31081067138,    1.80094525897-1
-2748.84912364596,    0.44864721776,    0.03383022891 1
-1467885.43202694017,    0.20844160209,    1.72470602676 534

CC   0.8178046763   0.0000000000   2 1
   0.99966651557:dLOD:

The "data" goes back to 1850!

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From this site https://psl.noaa.gov/data/20thC_Rean/timeseries/

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