{
  "abstract": "Optical Earth observation underpins a growing number of agricultural-monitoring and agri-fintech services across Africa, all of which need a usable view of a field often enough to track its condition. Cloud gaps in that record are usually treated as random missing data; we test whether they are instead structurally biased. Using three growing seasons (2022–2024) of Sentinel-2 scene-classification data over cropland in six administrative zones, one per African sub-region and together spanning the climate gradient from hyper-arid to humid-equatorial, we measure the weekly frequency with which each zone’s cropland yields a usable optical observation (a pixel passing the Sentinel-2 quality mask). This ranges from 55% over humid Central Africa to 81% over the arid Nile Delta; “blind-spot weeks”, when more than half a zone’s cropland is unobservable, run from 12% to 42%. Within every zone, usable-observation frequency falls as weekly rainfall rises (Spearman 𝜌 from −0.34 to −0.70, p < 0.001 after adjusting for temporal auto-correlation); this is the study’s one firmly powered result, and it reappears in an independent MODIS cloud product. With only six spatial units, the cross-regional climate gradient and the concentration of the deficit in the rain-fed growing season are reported as indicative patterns consistent with that rainfall mechanism, not as powered tests; Nile-irrigated Egypt inverts, as the mechanism predicts. Optical blind spots in African agricultural monitoring track rainfall and fall hardest on the humid, smallholder, rain-fed systems during their growing season, which motivates evaluating SAR-optical fusion for those zones. The study measures the gap, not the benefit of any fix.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 1,
  "authors": [
    {
      "name": "Olaoye Anthony Somide"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/4r0ad3p2ey6k5.bib",
  "cited_by": 0,
  "doi": "10.31223/x5j503",
  "fulltext_url": null,
  "id": "4r0ad3p2ey6k5",
  "issns": [],
  "landing_url": "https://eartharxiv.org/repository/view/14854/",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/legalcode",
  "metadata_licence": null,
  "native_subjects": [
    [
      "bepress",
      "Agriculture"
    ],
    [
      "bepress",
      "Environmental Studies"
    ],
    [
      "bepress",
      "Geographic Information Sciences"
    ],
    [
      "bepress",
      "Remote Sensing"
    ],
    [
      "bepress",
      "SAR fusion"
    ],
    [
      "bepress",
      "africa"
    ],
    [
      "bepress",
      "agricultural monitoring"
    ],
    [
      "bepress",
      "cloud cover"
    ],
    [
      "bepress",
      "earth observation"
    ],
    [
      "bepress",
      "observation bias"
    ],
    [
      "bepress",
      "optical remote sensing"
    ],
    [
      "bepress",
      "sentinel-2"
    ],
    [
      "bepress",
      "smallholder agriculture"
    ],
    [
      "openalex",
      "2303|Remote Sensing in Agriculture"
    ]
  ],
  "openalex": "W7211889402",
  "pdf_url": "https://eartharxiv.org/repository/object/14854/download/25820/",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-07",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/4r0ad3p2ey6k5.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:26Z",
      "native_id": "14854",
      "source": "eartharxiv",
      "url": "https://eartharxiv.org/repository/view/14854/"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "openalex:2303|Remote Sensing in Agriculture",
      "subfield": "ecology"
    }
  ],
  "title": "Cloud Cover and Structural Observation Gaps in African Agricultural Earth Observation: Evidence from Six Agroecological Zones",
  "title_text": "Cloud Cover and Structural Observation Gaps in African Agricultural Earth Observation: Evidence from Six Agroecological Zones",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:26Z",
  "url": "https://research.draconitic.com/paper/4r0ad3p2ey6k5",
  "venue": "EarthArXiv",
  "versions": []
}