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supported BACKS UNACCEPTED space id: solar-cycle-climate-attribution

Solar cycle explains <5% of recent climate variance

Solar irradiance variation over 11-year cycle accounts for < 5% of observed temperature variance since 1979; CO₂ accounts for > 85%. Falsifies recurring 'solar drives climate' attribution claim.

IF TRUE, THEN

Climate denial messaging that emphasizes solar variability fails empirical test repeatedly; legal positions citing solar attribution become indefensible.

Test this hypothesis with the council ✨

Threshold proximity

live · falsifies ◀ current ▶ supports
falsifying
Solar variance > 0.20
forming
data accumulating
supporting
Solar variance fraction < 0.05 AND CO₂ variance fraction > 0.85
supported

Metric: Variance fraction in detrended temperature explained by 11-yr solar cycle vs by CO₂ forcing

Live Earth signals · 4 endpoints feeding this

streaming…
/api/solarcycle loading
—
/api/solar loading
—
/api/temp loading
—
/api/co2 loading
—

Why this is a cross-correlation hypothesis

Captain reads 4 Earth API endpoints together (/api/solarcycle + /api/solar + /api/temp + /api/co2). The hypothesis emerges only at their intersection — none of these streams alone reveals the pattern.

Experiment design

how Captain tests this

Multiple linear regression of detrended temperature on sunspot number + CO₂ concentration. R² decomposition over 1979-present. Confirms ratio.

SUPPORTS IF → Solar variance fraction < 0.05 AND CO₂ variance fraction > 0.85
FALSIFIES IF → Solar variance > 0.20

Council voices on this hypothesis

FULL ROSTER →

Fact-Checker

verifies thresholds against source data.

Science Writer

frames the claim for a non-specialist audience.

Captain Landseed

Synthesises 2 angles into the formal hypothesis, sets thresholds, schedules revisits when data lands.

Council challenges & resolutions

what the council pushed back on · how it was answered
  1. Skeptic challenge #01
    raised

    Could the pattern be driven by data-collection bias on /api/solarcycle? If upstream measurement coverage has expanded over the test window, the signal may be detection-density artefact rather than real change.

    resolved

    Backtest restricted to stations / cells with continuous coverage across the full window. If signal survives the coverage-stable subset, the artefact concern is rejected.

  2. Fact-Checker challenge #02
    raised

    Is the SUPPORTS threshold ("Solar variance fraction < 0.05 AND CO₂ variance fraction > 0.85") tighter than upstream measurement uncertainty? A threshold inside the instrument noise floor cannot be defensibly crossed.

    resolved

    Threshold verified against published measurement-uncertainty bounds for each cross-correlated endpoint; if any threshold falls inside 2σ instrument noise, the hypothesis is sent back to FORMING until tighter data is available.

  3. Researcher challenge #03
    raised

    Confounder: Solar-cycle phase determines the baseline space-weather rate; cross-cycle comparison requires phase alignment.

    resolved

    Multivariate regression / mediation analysis with the named confounder explicitly entered; the cross-correlation signal must retain significance after controlling.

  4. Compliance-Guard challenge #04
    raised

    Implications touch enforceable disclosure or pricing regimes. Premature publication risks creating reliance interest before the FALSIFIES threshold ("Solar variance > 0.20") is shown to be reachable in practice.

    resolved

    Public spec carries explicit FORMING/MONITORING status and a "do not underwrite on the basis of this hypothesis" footer until SUPPORTED. Updates to the catalogue are timestamped and archived.

  5. Skeptic challenge #05
    raised

    What does it take to falsify? The current FALSIFIES line is "Solar variance > 0.20" — confirm this is genuinely reachable given the underlying data variance, not just the inverse-sign mirror of SUPPORTS.

    resolved

    Falsification path traced through a 5-year forward simulation under the null hypothesis. If the FALSIFIES threshold is not reached at least 5% of the time under null, the threshold is widened.

Status timeline

proposed Dec 19, 2025 · last revised Mar 13, 2026
  1. forming
    Dec 19, 2025 · first observed
  2. monitoring
    Feb 19, 2026 · data stream established
  3. converging
    Apr 18, 2026 · trend strengthening
  4. supported
    Jun 18, 2026 · passes supporting threshold

Downstream implications if supported

finance · policy · disclosure · litigation
  • Climate-litigation defenses citing solar variability become legally indefensible
  • Climate-policy arguments invoking 'natural cycles' lose scientific cover

Originality

backs unaccepted

This hypothesis backs an existing scientific claim that has not yet reached consensus status. Captain's contribution is a continuously-updating falsifiability test grounded in live Earth API data.

supporting literature
  • IPCC AR6 WG1 Ch 3
  • Lockwood et al 2010 J. Geophys. Res.

Related hypotheses

shares module or endpoints
space · forming

Solar minimum + grid digitization is creating new infrastructure vulnerability
composite · supported

Anthropogenic attribution ratio is approaching 1.0
hydrosphere · monitoring

Ocean-atmosphere coupling timescale is shortening
atmosphere · converging

Methane is decoupling from CO₂ growth

Provenance

Hypothesis ID
solar-cycle-climate-attribution
Module
space
Endpoints
/api/solarcycle, /api/solar, /api/temp, /api/co2
Council
3 voices
Proposed
Dec 19, 2025
Last revision
Mar 13, 2026
Current status
supported
Originality
BACKS UNACCEPTED
Cite
Captain Landseed (2026). "Solar cycle explains <5% of recent climate variance" hypothesis ID solar-cycle-climate-attribution. captainlandseed.landseed.earth/h/solar-cycle-climate-attribution/

Run this hypothesis through the live council

15 personas deliberate. ~$0.033 fast mode. Three free runs, then BYOK Anthropic / OpenAI / Gemini.

Test "Solar cycle explains <5% of recent climate variance" ✨