{ "schemaVersion": "climate-scientific-context/v1", "version": "research-v2026.09.16", "reviewedOn": "2026-09-16", "extraction": "Source-verified factual extracts and original paraphrases. These records complement, but do not replace, the frozen IGCC annual temperature series. They are not a new attribution analysis or an independent replication of the cited studies.", "sources": [ { "id": "IPCC-AR6-WGI-CH7", "title": "IPCC AR6 WGI (2021), Chapter 7", "url": "https://www.ipcc.ch/report/ar6/wg1/chapter/chapter-7/", "doi": "10.1017/9781009157896.009", "locator": "Heat inventory: section 7.2.2.2 and Table 7.1. Sensitivity: Box 7.1 and section 7.5.5.", "publisher": "IPCC / Cambridge University Press", "version": "AR6 Working Group I, 2021", "license": "Attributed factual extraction and paraphrase; report text and graphics are not redistributed.", "verification": "Relevant official HTML assessment, definitions and ranges checked." }, { "id": "FORSTER-2026-ENERGY", "title": "Forster et al. (2026), IGCC 2025", "url": "https://essd.copernicus.org/articles/18/3889/2026/", "doi": "10.5194/essd-18-3889-2026", "locator": "Section 6 and Table 4, 2013-2025 energy-imbalance row; interval definition in the table header.", "publisher": "Earth System Science Data", "version": "Published June 11, 2026", "license": "CC BY 4.0", "verification": "Primary HTML and publisher Table 4 XLSX checked; recent-period extrapolation retained." }, { "id": "PIERREHUMBERT-2011", "title": "Pierrehumbert (2011), Infrared radiation and planetary temperature", "url": "https://geosci.uchicago.edu/~rtp1/papers/PhysTodayRT2011.pdf", "doi": "10.1063/1.3541943", "locator": "Physics Today 64(1), pages 33-38; page 35, Figure 2, and the discussion of saturation.", "publisher": "Physics Today", "version": "January 2011, public author copy", "license": "Attributed factual extraction and original paraphrase; author PDF is linked, not redistributed.", "verification": "Relevant text in the public author copy checked.", "verifiedDocumentSha256": "d0eefe18918bbb5e6a76fc9a31945985b267675ac0236c54a7ce64cf403be0a4" }, { "id": "FELDMAN-2015", "title": "Feldman et al. (2015), Observational determination of surface radiative forcing", "url": "https://www.osti.gov/servlets/purl/1512180", "doi": "10.1038/nature14240", "locator": "Nature 519, pages 339-343; results and Figure 4; Methods, Trend determination.", "publisher": "Nature; public author copy hosted by the US Department of Energy", "version": "2015", "license": "Attributed factual extraction and original paraphrase; author PDF is linked, not redistributed.", "verification": "Open full text, results and relevant methods checked. The headline plus/minus convention is retained as reported uncertainty, without assigning an unverified confidence level.", "verifiedDocumentSha256": "7f043cca29e2c392fef743fec95ca20d53e1d2410033b74b2d590df75abffd00" }, { "id": "HAWKINS-JONES-2013", "title": "Hawkins and Jones (2013), 75 years after Callendar", "url": "https://www.met.reading.ac.uk/~ed/home/hawkins_jones_2013_Callendar.pdf", "doi": "10.1002/qj.2178", "locator": "Quarterly Journal of the Royal Meteorological Society 139, pages 1961-1963; accepted manuscript pages 2-3, section 2, Figure 1 and footnote.", "publisher": "Quarterly Journal of the Royal Meteorological Society", "version": "2013, accepted manuscript", "license": "Attributed factual extraction and original paraphrase; manuscript is linked, not redistributed.", "verification": "Published reanalysis, comparison domain, reference period and reported correlation checked. The reanalysis was not independently rerun.", "verifiedDocumentSha256": "ebdf9fd71f4648f4b8efcb6d62d2783da9baad3e79ae58b87ca754ffb9e2c262" } ], "records": [ { "id": "ocean-heat-share", "title": "Most of the extra energy went into the ocean.", "status": "externally-assessed", "statusLabel": "Assessed heat inventory", "period": "1971-2018", "value": "91", "unit": "%", "valueLabel": "Ocean share of Earth-system energy gain", "finding": "The IPCC assessed that the ocean accounted for 91% of the energy gained by the climate system during 1971-2018. A surface-temperature series therefore describes only one part of a much larger heat inventory.", "method": "The assessment combines estimates of heat accumulated in the ocean, land, atmosphere and cryosphere. The percentage refers to the ocean's share of the total energy gain over the stated period, not to the fraction of incoming sunlight absorbed by the ocean.", "limitation": "This is a share of accumulated energy, not a temperature change or a newly measured percentage for 2025. It does not locate regional ocean changes.", "sourceIds": [ "IPCC-AR6-WGI-CH7" ] }, { "id": "planetary-imbalance", "title": "The planet's energy account remained positive.", "status": "observation-based-assessment", "statusLabel": "Observation-based assessment", "period": "2013-2025 average", "value": "1.12", "unit": "W/m²", "valueLabel": "Mean Earth energy imbalance", "finding": "IGCC 2025 estimates an average energy imbalance of 1.12 W/m² during 2013-2025, with a 90% confidence interval of 0.78-1.46 W/m². The denominator is Earth's entire surface, and a positive value means that the climate system gained energy overall.", "method": "Section 6 derives the imbalance from an observation-based energy inventory. For 2021-2025, ocean uptake is scaled to total-system uptake using an assumed 91% ocean share because the other components extend only through 2020. Assessed heating rates and uncertainties below 2,000 m are held constant over the period.", "limitation": "This is a multiyear mean, not the imbalance of 2025 alone. It is neither CO2 radiative forcing nor an annual surface-temperature anomaly.", "sourceIds": [ "FORSTER-2026-ENERGY" ] }, { "id": "infrared-band", "title": "CO2 interacts with identifiable infrared wavelengths.", "status": "physical-mechanism", "statusLabel": "Spectroscopic mechanism", "period": "Physical explanation / 2011 synthesis", "value": "~15", "unit": "µm", "valueLabel": "An important CO2 infrared band", "finding": "An important CO2 bending band lies near 667 cm⁻¹, corresponding to approximately 15 micrometers. Its spectral structure gives the greenhouse explanation a physical signature that can be examined in radiation measurements.", "method": "Molecular absorption and emission vary with wavelength, pressure and temperature. The cited synthesis connects laboratory spectroscopy, radiative-transfer physics and observed atmospheric spectra. In relevant spectral regions, additional CO2 changes the levels from which radiation effectively escapes to space.", "limitation": "This is a band, not CO2's only absorption wavelength. Its position alone does not quantify global warming. Absorption is not reflection from a glass roof, and saturation of a line center does not eliminate the effect of additional CO2.", "sourceIds": [ "PIERREHUMBERT-2011" ] }, { "id": "measured-co2-forcing", "title": "The expected radiative change was measured at two sites.", "status": "measurement-and-calculation", "statusLabel": "Measurements + radiative transfer", "period": "2000-2010", "value": "0.20", "unit": "W/m² per decade", "valueLabel": "Approximate CO2-related surface-forcing trend", "finding": "Feldman and colleagues reported increases of approximately 0.20 ± 0.06 W/m² per decade at Southern Great Plains and 0.20 ± 0.07 at North Slope of Alaska. These are the paper's reported uncertainties; no additional confidence label is assigned here.", "method": "Infrared measurements, ancillary observations and radiative-transfer calculations isolate the changing CO2 contribution to downward surface radiation under clear skies. The study examined a period in which atmospheric CO2 increased by about 22 ppm. Its method is measurement-based, not model-free.", "limitation": "Two-site clear-sky surface forcing is not global top-of-atmosphere forcing or total planetary energy imbalance. Neither this trend nor the spectral band alone estimates equilibrium climate sensitivity.", "sourceIds": [ "FELDMAN-2015" ] }, { "id": "callendar-reconstruction", "title": "A historical temperature record survived a later comparison.", "status": "published-reanalysis", "statusLabel": "Published retrospective comparison", "period": "1938 reconstruction / 2013 reanalysis", "value": "0.81", "unit": "correlation r", "valueLabel": "Callendar reconstruction versus CRUTEM4", "finding": "Hawkins and Jones compared Callendar's 147-land-station reconstruction with CRUTEM4 and reported a correlation of 0.81. They aligned the geographic domain to land between 60°S and 60°N and used an 1880-1935 anomaly reference.", "method": "The published reanalysis compares historical land-temperature reconstructions over their common historical period. This checks agreement in the reconstructed pattern under a common domain and reference; it does not turn the two reconstructions into independent experiments. No reanalysis is rerun on this page.", "limitation": "A correlation of 0.81 is not 81% accuracy. Agreement does not validate every historical CO2 observation, radiative assumption or attribution claim, and a land-only comparison is not the global land-ocean record plotted above.", "sourceIds": [ "HAWKINS-JONES-2013" ] }, { "id": "equilibrium-sensitivity", "title": "Climate sensitivity answers a different temperature question.", "status": "externally-assessed", "statusLabel": "Assessed response to CO2 doubling", "period": "AR6 assessment / equilibrium response", "value": "3.0", "unit": "°C", "valueLabel": "Best estimate of equilibrium climate sensitivity", "finding": "AR6 assesses a best estimate of 3.0°C for equilibrium climate sensitivity, with a likely range of 2.5-4.0°C. The quantity is a global surface-air-temperature response to doubled atmospheric CO2 concentration after the planetary energy budget balances.", "method": "The assessment combines understanding of feedbacks, the instrumental record, paleoclimate evidence and other constraints. Its likely range is an assessed uncertainty range, not simply the smallest and largest outputs from a collection of models. The metric excludes slow ice-sheet feedbacks.", "limitation": "This is not the observed 2025 global mean surface-temperature anomaly, an emissions-per-tonne coefficient, or a forecast for a particular calendar year. Ocean heat uptake and the time path of forcing matter for the transient response.", "sourceIds": [ "IPCC-AR6-WGI-CH7" ] } ], "assessmentCorrections": [ { "recordId": "observed-year", "field": "locator", "original": "Section 7, Table 5", "corrected": "Section 7, annual-result paragraph; Table 6, Observed row, column (b)(iii)", "reason": "Table 5 reports decadal estimates. The 2025 observed annual estimate is in section 7 and Table 6. Numerical values and likelihood labels are unchanged; the original raw extract is retained.", "reviewedOn": "2026-09-16", "sourceUrl": "https://essd.copernicus.org/articles/18/3889/2026/" } ], "sourceSha256": "57f5215c590e5d6d2961f37b2967357305995cfb39f5fb402fdb8ef3478b2f3e", "checksumConvention": "SHA-256 of the frozen UTF-8 source extract with LF line endings." }