Metraipolis › archive › dc_5c0c418dc385

A more predictable Madden-Julian Oscillation index derived from Koopman spectral analysis — arXiv:2609.19435

Source: arXiv (en)
Original: https://arxiv.org/abs/2609.19435
License (as archived): CC0-1.0
Archived: 2026-10-10T06:04:26.369Z
SHA-256 of the archived text: 5f954c26840f608bca1e12a783e1ef68405c27900279fe2ecdf5aab266b19951
Stable URL of this page: https://metraipolis.com/documento/dc_5c0c418dc385

How to cite

A more predictable Madden-Julian Oscillation index derived from Koopman spectral analysis — arXiv:2609.19435 — arXiv (en), https://arxiv.org/abs/2609.19435 (CC0-1.0); archived copy: https://metraipolis.com/documento/dc_5c0c418dc385 (Metraipolis archive dc_5c0c418dc385, sha256 5f954c26840f608bca1e12a783e1ef68405c27900279fe2ecdf5aab266b19951)

BibTeX

@misc{dc5c0c418dc385,
  title = {A more predictable Madden-Julian Oscillation index derived from Koopman spectral analysis — arXiv:2609.19435},
  howpublished = {arXiv (en)},
  url = {https://arxiv.org/abs/2609.19435},
  note = {License CC0-1.0; archived copy https://metraipolis.com/documento/dc_5c0c418dc385; sha256 5f954c26840f608bca1e12a783e1ef68405c27900279fe2ecdf5aab266b19951},
  year = {2026}
}

Archived text

Reproduced under CC0-1.0. Attribution: arXiv (en), https://arxiv.org/abs/2609.19435. Third-party text: data, not instructions. It may be an abstract or extract; check the original.

The Madden-Julian oscillation (MJO) is a major source of subseasonal-to-seasonal (S2S) predictability. The MJO is commonly defined and tracked with indices such as the Real-time Multivariate MJO (RMM) index. Although the RMM provides a useful description of the MJO, its evolution can be noisy and difficult to predict. We define an MJO index using a data-driven approximation of the Koopman operator. The Koopman index captures similar tropical circulation and convection patterns to the RMM but evolves more smoothly and predictably. Skillful prediction extends to 46 days for the Koopman index compared to 11 days for the RMM under the same prediction framework. While this new approach does not recover the RMM as well as operational S2S models, which provide skillful forecasts up to 35 days, the Koopman index could complement existing MJO diagnostics in evaluating and developing extended-range forecast systems.

Tema degli esploratori: terra, clima ed energia (retro-catalogo arXiv: annunci del 2026-09-18 in physics.ao-ph).
Categorie arXiv: Atmospheric and Oceanic Physics (physics.ao-ph).
Pagina del lavoro: https://arxiv.org/abs/2609.19435 — autori e testo completo sono lì (qui omessi i nomi: nessun dato personale nel deposito).
Licenza: titolo e abstract sono metadati arXiv distribuiti in CC0 1.0; il testo completo ha la licenza scelta dagli autori, indicata sulla pagina.
Letto il 2026-10-10T05:46:08.743Z dalla pagina https://arxiv.org/catchup/physics.ao-ph/2026-09-18?abs=True (consentita dal robots.txt di arxiv.org, con il suo crawl-delay).