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Climate Change Data Stories

The evidence contract

Sources, methods, and limits.

The IPCC is the scientific frame. A newer observation updates an indicator; it does not silently replace an assessment.

The AR6 structure

SPM.A: Current Status and Trends
Observed change, impacts, and the gaps in adaptation and mitigation.
SPM.B: Future Climate Change, Risks and Long-Term Responses
Warming levels, carbon budgets, irreversibility, and conditional pathways.
SPM.C: Responses in the Near Term
Technology, policy, equity, adaptation, and the finance that enables action.

The 2023 Synthesis Report integrates the Sixth Assessment cycle. Newer observations are marked as post-AR6 updates. Pathways are conditional scenarios, not forecasts.

The first imported dataset

Indicators of Global Climate Change 2025: global mean surface temperature, v2026.06.02. 176 annual observational estimates, 1850–2025, in degrees Celsius relative to 1850–1900. Retrieved 2026-09-08; CC BY 4.0.

Read GMST as published; use timebound_lower as year. Arithmetic complete trailing means, fixed calendar decades and annual differences; no rebasing, imputation or causal estimation.

The compact annual file has no row-level uncertainty. Published assessment intervals are separate, sourced records, not inferred from annual fluctuations.

Source receipt and SHA-256 / Exact annual data / Published assessment extract

What the numbers mean

  • Annual warmth, a trailing mean, and human-induced warming answer different questions. A single hot year does not establish a sustained global warming level.
  • Anomaly baselines stay explicit. NASA GISTEMP uses 1951–1980; the IGCC pilot uses 1850–1900. These products are not merged with a generic offset.
  • Observed, estimated, derived, and projected quantities retain their status. Missing data never become zeros.
  • Exposure, vulnerability, damages, and attribution remain separate. Changing asset values, population, reporting, and protection can change losses without identifying a climate effect.
  • Source likelihood and confidence terms retain their calibrated meaning. No error bands are invented from year-to-year variation.
  • IPCC Figure SPM.7 mitigation potentials are independently assessed and not additive. Table SPM.1 uses reductions relative to 2019 with percentile ranges.

The source shortlist

These 18 products come from the programme's supplied source index. Only the IGCC pilot import has passed the data checks in this release. Other products remain candidates; coverage, licensing, and joins will be verified for each study.

How questions are prioritized

The backlog uses ten editorial dimensions scored from zero to five. Their weighted sum is multiplied by 20 for a zero-to-100 score. Interpretation safety reverses the risk score: five means lower misleading-interpretation risk. Ties use the stable story ID. These scores rank research priorities, not climate outcomes.

scientific Relevance
15%
source Authority
15%
freshness
10%
data Manageability
10%
visual Potential
10%
analytical Depth
10%
originality
5%
audience Relevance
10%
reproducibility
10%
interpretation Safety
5%

Reproducibility and corrections

The raw IGCC release is frozen by version and checksum. A deterministic processing script generates the exact data, figures, and data-quality report. A changed source requires a new reviewed snapshot; it does not overwrite the historical input. Corrections must identify the affected quantity, version, and consequence for the story.

Primers have permanent addresses but are excluded from completed-publication discovery. A study is promoted only after its source, arithmetic, uncertainty, attribution, rights, and rendering checks pass.

Images and rights

Photographs and satellite images supply context, not evidence of a trend. The historical date and location belong to each image, not to the story's dataset. Images are cropped or fitted for the page; quantitative chart values are not encoded in them.

NASA informational and editorial reuse guidance applies. No NASA endorsement is implied.

  • NASA/GSFC/Michael StudingerThe calving front of Gyldenlove Glacier in southeast Greenland, photographed during Operation IceBridge in 2011. Centered editorial crop, no alteration of depicted conditions.
  • NASA/Apollo 17 crewEarth with Africa and Antarctica visible, photographed by the Apollo 17 crew on December 7, 1972. Full frame fitted with a native dark-canvas surround.
  • NASA/STS-44 crewSunlight revealing internal-wave patterns in the western Indian Ocean, photographed from Atlantis in 1991. Centered editorial crop, no alteration of depicted conditions.
  • NASA/STS-43 crewSediment at the mouths of the Amazon River on Brazil's Atlantic coast, photographed from space in 1991. Centered editorial crop, no alteration of depicted conditions.
  • NASA Earth Observatory/LandsatLandsat imagery of Lake Powell and its exposed shoreline in May 2014. Centered editorial crop, no alteration of depicted conditions.
  • NASA/STS-43 crewThe Amazon and Tapajos rivers meeting near Santarem, Brazil, with forest and cleared land visible in a 1991 space photograph. Centered editorial crop, no alteration of depicted conditions.
  • NASA Glenn Research CenterThe experimental Mod-1 wind turbine in Boone, North Carolina, in 1979; historical energy-technology context. Centered editorial crop, no alteration of depicted conditions.
  • NASA/Kennedy Space CenterRows of solar panels at the Discovery Solar Energy Center in Florida, photographed in April 2021. Centered editorial crop, no alteration of depicted conditions.
  • NASA/Chris WilliamsParis and the Seine photographed from the International Space Station on April 4, 2026; urban context, not a heat map. Centered editorial crop, no alteration of depicted conditions.

Image provenance and derivative checksums