maurice blackmon and two dimensional spectral analysis: the power and the glory joe tribbia ncar
TRANSCRIPT
Maurice Blackmon and two dimensional spectral analysis:
The power and the glory
Joe TribbiaNCAR
No, not that power and glory!
Title Disclaimer
“All history is LIES agreed upon” Napoleon*
*Attributed by Barbara Tuchman
Noted historian
Historical Disclaimer
Celebrate 1st Publication in Atmospheric Science
Early 1970s Transition Particle Physics -- Atmospheric science
One career/hobby for another
Maurice’s One True Vocation
On to the power…..
Computed Spherical harmonic spectra of 500mb height
ComputedSpectra forWinter and Summer1963-72
Many tables with lots of numbers (Power)
Power in Frequency domain vsTwo dimensionalWavenumber (n)
Power for fixedFrequency forEach SphericalHarmonic
Comparison with 1990s
0.5 0.2 0.1 0.3 0.2 0.2 0.2 0.2 0.1 0.1 0.1 0.3 0.4 0.3 0.2 1.0 0.3 0.7 0.5 0.2 0.3 0.2 0.7 0.3 0.3 0.4 0.7 0.5 0.3 0.4 0.5 0.2 0.3 0.9 0.9 1.4 2.4 1.7 0.7 1.3 0.6 0.5 1.0 0.2 1.4 0.9 2.4 0.9 5.7 2.4 1.1 1.3 0.6 0.6 0.2 1.4 0.9 2.2 2.9 5.4 4.8 2.6 2.3 3.0 1.0 0.1 2.7 3.2 1.6 4.0 26.2 33.7 13.9 10.8 1.5 0.7 0.1 1.1 5.5 7.1 22.9 34.8 46.9 20.0 10.2 2.6 0.1 0.0 2.5 1.3 3.3 21.1 66.2 75.5 48.5 7.5 0.6 0.0 0.0 5.2 5.7 6.0 22.3 101.9 47.3 26.8 1.6 0.1 0.0 0.0 2.5 10.7 12.5 37.5 65.3 18.8 6.5 0.1 0.0 0.0 0.0 9.3 19.3 7.9 3.9 48.3 2.9 0.6 0.0 0.0 0.0 0.0 4.6 10.5 5.9 9.7 5.4 0.2 0.0 0.0 0.0 0.0 0.0 10.3 14.6 5.0 1.7 0.7 0.0 0.0 0.0 0.0 0.0 0.0 4.3 3.1 1.0 1.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 13.8 5.2 6.9 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 5.5 1.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 10.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
5 day powerWinter ’63-72
5day powerJFM ’90-99
Comparison with 1990s
0.5 0.5 0.7 0.2 0.7 0.3 0.2 0.1 0.2 0.1 0.1 1.1 1.2 1.1 0.9 1.1 0.8 0.6 0.2 0.2 0.1 0.1 1.6 3.3 1.5 0.6 0.2 1.0 0.4 0.4 0.2 0.1 0.1 2.5 2.1 1.3 1.3 1.4 1.2 1.7 0.6 0.3 0.2 0.1 4.3 11.4 5.4 4.0 4.2 2.6 1.5 1.2 0.5 0.2 0.1 3.1 19.7 6.8 13.8 17.4 8.0 1.8 1.5 1.8 1.3 0.1 38.2 72.0 41.3 15.6 6.6 16.3 2.5 6.3 2.3 0.4 0.1 18.8 85.0 68.1 48.5 4.2 12.6 27.2 2.9 3.7 0.3 0.0 44.1 512.0 614.4 191.8 331.4 43.4 28.9 16.5 1.3 0.1 0.0 190.6 286.1 282.2 3032.6 402.3 250.5 14.4 1.6 0.2 0.0 0.0 221.8 416.1 3408.6 1427.7 1031.9 269.8 9.2 0.7 0.0 0.0 0.0 188.5 1125.9 4560.2 7291.8 1058.7 78.2 0.6 0.0 0.0 0.0 0.0 1334.6 4429.1 1568.8 976.4 103.8 16.3 0.0 0.0 0.0 0.0 0.0 901.5 3587.0 4454.9 564.3 32.5 0.0 0.0 0.0 0.0 0.0 0.0 5179.1 7054.1 109.4 11.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1073.8 634.5 31.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 816.6 46.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 10.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
15 day powerWinter ’63-72
15 day powerJFM ’90-99
Enough power,on to the glory….
Introduced (now classic)bandpass filters
Compare variance with 1990’s
Total Winter RMS Amplitude
Nine yearWinter mean
Total JFM RMSAmplitude
Ten yearJFM mean
Lowpass Regime I (1963-72)Winter RMS amplitude
All waves Regime I
Lowpass Regime I (1990s)JFM RMS amplitude
All waves Regime I
Three Centers of low frequency variability
• Pacific (Blocking and PNA)
• Atlantic (Blocking and NAO)
• Eurasian (?)
• Inspiring research up to present day
Great beginning of 2nd career/hobby
“Well begun is half done”Mary Poppins*
Maurice was just warming up
*Attributed by noted historian
Joe Tribbia