Short description of the diagnostic
The diagnostic produces an MJO (Madden-Julian Oscillation) precipitation lag-regression Hovmöller diagram — a longitude-vs-lag plot showing the eastward propagation of MJO convection.
- Takes daily tropical (±15°N) precipitation on a regular grid.
- Removes the day-of-year climatology to get daily anomalies.
- Band-pass filters those anomalies to the 20–100 day MJO band with a Lanczos filter, to remove seasonal/dirunal signals.
- Builds a reference index by averaging the filtered field over 80–100°E.
- Regresses the full filtered longitude field against that index at lags from −25 to +25 days.
The result is a 2-D field (lag × longitude) of regression coefficients: a diagonal band sloping from lower-left to upper-right (west to east with increasing lag) is the visual signature of the MJO's eastward-propagating precipitation envelope. For more details see Hannah et al. 2020 (Figure 9).
https://doi.org/10.1029/2019MS001863
Branch and pull request
Branch: hovmoeller_mjo
Short description of the diagnostic
The diagnostic produces an MJO (Madden-Julian Oscillation) precipitation lag-regression Hovmöller diagram — a longitude-vs-lag plot showing the eastward propagation of MJO convection.
The result is a 2-D field (lag × longitude) of regression coefficients: a diagonal band sloping from lower-left to upper-right (west to east with increasing lag) is the visual signature of the MJO's eastward-propagating precipitation envelope. For more details see Hannah et al. 2020 (Figure 9).
https://doi.org/10.1029/2019MS001863
Branch and pull request
Branch: hovmoeller_mjo