{
  "annotation_id": "d8d409e4-74e5-4989-b167-54e1cc812228",
  "date_created": "2026-03-02T18:01:21.879000Z",
  "date_modified": "2026-03-02T18:01:21.879000Z",
  "file_hash": "b94239fc8f2c972f2ccb1f15eb15332587df40aa0456ca0177d21ca164f91c61",
  "private": false,
  "record": {
    "abstract": "The adjoint of an ocean general circulation model is used as a tool for\ninvestigating the causes of changes in ENSO SST indices. We identify adjoint\nKelvin and Rossby waves in the sensitivities to sea level and wind stress at\nearlier times, which can be traced back for more than a year through western\nand weak eastern boundary reflections. Depending on the thermocline depth the\nfirst and second baroclinic modes are excited. The sensitivities to the heat\nflux and SST are local and decay in about a month. The sensitivities to the\nfluxes are converted into the influence of SST using the adjoint of a\nstatistical atmosphere model. Focusing on SST perturbations in the index region\nitself, we recover, up to a scale factor, the delayed oscillator concept.",
    "arxiv_id": "physics/9708037",
    "authors": [
      "Geert Jan van Oldenborgh",
      "Gerrit Burgers",
      "Stephan Venzke",
      "Christian Eckert",
      "Ralf Giering"
    ],
    "categories": [
      "physics.ao-ph",
      "physics.comp-ph"
    ],
    "title": "Tracking down the ENSO delayed oscillator with an adjoint OGCM",
    "url": "https://arxiv.org/abs/physics/9708037"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "dee6ff23-72b2-495c-b736-d2a4d12889eb",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}