{
  "abstract": "The North Atlantic Oscillation (NAO) is widely recognised as the leading mode of atmospheric variability over the North Atlantic (90°W-40°E, 20°-80°N). However, its broad-scale dipole fails to fully explain climate variability at mid-latitudes around Western Europe, where coastal storm and hydroclimatic impacts remain poorly captured. Here, using monthly mean sea-level pressure (SLP) from the ERA5 reanalysis (1950-2024), we apply empirical orthogonal function (EOF) analysis to identify dominant regional pressure modes across the Eastern part of the North Atlantic sector (25°W-15°E, 20°-65°N). The leading mode corresponds to the West Europe Pressure Anomaly (WEPA), while the second reproduces the canonical NAO pattern. Together, these modes explain between 67% and 78% of the seasonal SLP variance. The WEPA exhibits a remarkably stable spatial structure throughout the annual cycle and is strongly correlated with precipitation, near-surface wind speed and significant wave height along the Atlantic coast of Western Europe, demonstrating that it represents a persistent regional mode of atmospheric variability rather than a winter-specific empirical index. Future projections based on CMIP6 simulations indicate only modest changes in WEPA under the SSP2-4.5 scenario. Although a weak decrease in the ensemble-mean index is detected when all ensemble members are considered, this trend is not reproduced when analyses are performed using one ensemble member per model, suggesting limited evidence for a robust multi-model climate response. These results establish WEPA as a fundamental mode of atmospheric variability governing Western European climate while indicating that its future evolution remains uncertain relative to the large internal variability of the climate system.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "name": "Ramdane Alkama"
    },
    {
      "name": "Didier Swingedouw"
    },
    {
      "name": "Bruno Castelle"
    },
    {
      "name": "Christophe Cassou"
    },
    {
      "name": "Joanne Couallier"
    },
    {
      "name": "Theodore Raymond"
    },
    {
      "name": "Jérôme Ogée"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1h1zvcvpcgvyx.bib",
  "cited_by": 1,
  "doi": "10.1007/s00382-026-08420-9",
  "fulltext_url": null,
  "id": "1h1zvcvpcgvyx",
  "issns": [
    "0930-7575",
    "1432-0894"
  ],
  "landing_url": "https://hal.science/hal-05843944v1",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "hal",
      "0.sdu"
    ],
    [
      "hal",
      "1.sdu.ocean"
    ],
    [
      "hal",
      "1.sdu.stu"
    ],
    [
      "hal",
      "2.sdu.stu.cl"
    ],
    [
      "openalex",
      "2306|Climate variability and models"
    ]
  ],
  "openalex": "W7223297689",
  "pdf_url": "https://hal.science/hal-05843944/document",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-29",
  "publisher": "Springer Verlag",
  "ris": "https://research.draconitic.com/paper/1h1zvcvpcgvyx.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:03Z",
      "native_id": "hal-05843944",
      "source": "hal",
      "url": "https://hal.science/hal-05843944v1"
    }
  ],
  "subjects": [
    {
      "field": "earth",
      "origin": "hal:2.sdu.stu.cl",
      "subfield": "climate"
    },
    {
      "field": "earth",
      "origin": "hal:1.sdu.ocean",
      "subfield": "oceanography"
    }
  ],
  "title": "A persistent atmospheric pressure mode governs western Europe’s seasonal climate",
  "title_text": "A persistent atmospheric pressure mode governs western Europe’s seasonal climate",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T12:20:56Z",
  "url": "https://research.draconitic.com/paper/1h1zvcvpcgvyx",
  "venue": "Climate Dynamics",
  "versions": []
}