CLIVAR MJO Diagnostics — HyCAM.ftorch.2d.seq2.seed.333.nl.22.128.ep.100 (5 yr, F2000)

Built from the daily (h1) HyCAM output using NCL's CLIVAR-MJO functions (mjo_xcor_lag, combined-EOF eofunc, phase-composite). Anomalies = smoothed-daily-climatology removed; 20–100 day Lanczos band-pass. Observational reference = ERA + TRMM (reused from xsongsio's published CLIVAR-MJO obs on the E3SM portal). model = orange/green panels obs = ERA

1. Lag cross-correlation (Indian-Ocean precip base; lag–lon top, lag–lat bottom)

Eastward tilt of the correlation band = eastward MJO propagation. Precip (color), U850 (contours).

HyCAM — winter

ERA — winter

HyCAM — summer

ERA — summer

HyCAM — annual

ERA — annual

2. Combined (multivariate) EOF of OLR + U850 + U200 [15S–15N]

EOF1 & EOF2 are the canonical MJO mode pair (HyCAM: 20.2% & 16.5% variance). Below: HyCAM combined-EOF; ERA single-field EOFs for reference.

HyCAM — EOF1 & EOF2 (OLR/U850/U200)

ERA OLR EOF (winter)

ERA U850 EOF (winter)

ERA U200 EOF (winter)

3. Composite life cycle (8 MJO phases; OLR anom + 850-hPa wind vectors)

Days with MJO index ≥ 1 composited by phase; eastward march of convection through the 8 phases.

HyCAM — summer (May–Oct)

HyCAM — winter (Nov–Apr)

ERA — life cycle

4. Seasonal wavenumber–frequency spectra (per variable, 15S–15N)

Power vs zonal wavenumber & frequency; eastward (positive freq) MJO band at wavenumber 1, 30–80 day periods. HyCAM model vs ERA obs.

Winter:

HyCAM OLR

ERA OLR

HyCAM U850

ERA U850

HyCAM U200

ERA U200

HyCAM PRECT

Summer:

HyCAM OLR

ERA OLR

HyCAM U850

ERA U850

HyCAM U200

ERA U200

HyCAM PRECT

5. Wheeler–Kiladis spectra (companion page)

The full WK spectra (OLR/PRECT/U200/U850/OMEGA500, raw/background/normalized, sym+asym) vs NOAA/NCEP obs + the MJO index & χ200 Hovmöller are on the companion variability page:

→ HyCAM.ftorch.2d AMWG Variability page (Wheeler–Kiladis + MJO index + χ200)

Generated 2026-06-06. Model = HyCAM.ftorch.2d (FTorch ResCu NN, F2000, 5 yr daily). Obs reference ERA/TRMM reused from xsongsio (E3SM CLIVAR-MJO output).