Will NASA GISS report a global surface temperature anomaly of at least +1.40 °C (vs. 1951–1980) for November 2026?
échéance 2026-12-20
confiance moyenne
preuve niveau 1
58 %estimation PolySignal
Critère de résolution
Resolves YES if the NASA GISS file GISTEMP v4 land-ocean monthly means (https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.csv), read for the first time on or after 2026-12-20, shows a value >= +1.40 °C for November 2026 (row 2026, column Nov). The value read at that moment is final; later revisions do not change the outcome. If the value is not yet published on 2026-12-20, the check is repeated until 2026-12-30, after which the question is voided. Also voided if NASA changes the dataset version or the 1951–1980 baseline. Reference at creation: +1.38 °C (September 2026). Data: GISTEMP Team, GISS Surface Temperature Analysis (GISTEMP), version 4, NASA Goddard Institute for Space Studies.
État de départ vérifié
Computed base rate: 46% of two-month changes in the NASA GISTEMP monthly anomaly since 1990 reached the change implied by this threshold (threshold 1.4 °C rounded up to 0.05 °C; reference 1.38 °C in 2026-09). Overlapping windows: small effective sample.
Les arguments ci-dessous ont été produits par le modèle en anglais. Ils sont affichés tels quels plutôt que traduits automatiquement, pour que rien sur cette page ne soit un texte que PolySignal n'a pas réellement écrit.
Ce qui fait monter
- September 2026 is already at a high baseline of +1.38 °C, requiring only a small +0.02 °C increase by November 2026 [1].
- Global climate warming trends and recent autumn temperature patterns frequently yield monthly GISTEMP anomalies above +1.40 °C [1].
Ce qui fait descendre
- Short-term internal climate variability and fluctuations in ocean surface temperatures could lower the anomaly below +1.40 °C [1].
- Early Copernicus ERA5 indicators for October show a moderate anomaly (+0.79 °C vs 1991–2020), indicating no immediate sharp spike in global heat [1].
Ce qui ferait le plus bouger ce chiffre
Natural short-term global temperature variability and tropical ocean conditions between September and November 2026.
Comment ce chiffre est fabriqué
| Échéance | 2026-12-20 |
| Taux de base | 46% |
| Meilleure preuve | niveau 1 · 1 article(s) utilisé(s) |
| Estimations | 48 · 58 · 62 (écart 14 pts) |
| Confiance | moyenne |
| Plafond de preuve | non déclenché |
| Révisée le | 2026-10-11 13:31 |
| Modèle | gemini-3.5-flash |
Sources consultées
Historique de la probabilité
2026-10-11 13:31 58% 0 article(s) au dossier · gemini-3.5-flash
- Ce qui fait monter. September 2026 is already at a high baseline of +1.38 °C, requiring only a small +0.02 °C increase by November 2026 [1].
- Ce qui fait monter. Global climate warming trends and recent autumn temperature patterns frequently yield monthly GISTEMP anomalies above +1.40 °C [1].
- Ce qui fait descendre. Short-term internal climate variability and fluctuations in ocean surface temperatures could lower the anomaly below +1.40 °C [1].
- Ce qui fait descendre. Early Copernicus ERA5 indicators for October show a moderate anomaly (+0.79 °C vs 1991–2020), indicating no immediate sharp spike in global heat [1].
- Ce qui ferait le plus bouger ce chiffre. Natural short-term global temperature variability and tropical ocean conditions between September and November 2026.
2026-10-11 09:13 42% 0 article(s) au dossier · gemini-3.7-flash
- Ce qui fait monter. August 2026 started at +1.40 °C, meaning only a modest rise of +0.05 °C across two months is needed to hit the +1.45 °C threshold [tier 1].
- Ce qui fait monter. Early Copernicus ERA5 data for the first 9 days of October 2026 shows a strong anomaly of +0.79 °C vs 1991–2020, pointing toward elevated global warmth [tier 1].
- Ce qui fait descendre. Historically, only 38% of two-month increments sustain a +0.05 °C increase, indicating month-to-month cooling or stagnation is frequent [tier 1].
- Ce qui fait descendre. Nine days of ERA5 reanalysis provide only a partial month signal with substantial intra-month volatility and known differences from GISTEMP processing [tier 1].
- Ce qui ferait le plus bouger ce chiffre. Whether global temperatures remain elevated through the remainder of October 2026 or cool down as month-to-month noise reverts.
2026-10-08 20:59 25% 0 article(s) au dossier · gemini-3.5-flash
- Ce qui fait monter. The base rate of 38% represents a significant historical probability of reaching the threshold [1].
- Ce qui fait monter. September 2026 ERA5 anomaly maps to a warm +1.39 °C in GISTEMP, keeping the baseline relatively high [1].
- Ce qui fait descendre. Early October 2026 ERA5 data (first 6 days) shows a lower anomaly of +0.73 °C, which is a drop from September's +0.82 °C [1].
- Ce qui fait descendre. A projected October GISTEMP anomaly based on early ERA5 data points to roughly +1.30 °C, well below the +1.45 °C threshold [1].
- Ce qui ferait le plus bouger ce chiffre. The temperature trend over the remaining 25 days of October 2026, which could deviate significantly from the first 6 days.
2026-10-08 19:45 30% 0 article(s) au dossier · gemini-3-flash-preview
- Ce qui fait monter. Long-term anthropogenic warming trend increases the frequency of monthly anomalies exceeding +1.40 °C [1]
- Ce qui fait monter. The August 2026 anomaly of +1.40 °C provides a high starting point for the two-month window [1]
- Ce qui fait descendre. The September 2026 ERA5 proxy of +0.82 °C suggests a GISTEMP equivalent of approximately 1.39 °C, which is below the target [1]
- Ce qui fait descendre. Preliminary ERA5 data for the first 6 days of October (+0.73 °C) indicates a cooling trend relative to September, mapping to roughly 1.30 °C in GISTEMP [1]
- Ce qui ferait le plus bouger ce chiffre. The high volatility of monthly temperature anomalies and the fact that only 6 days of October data are currently available.