One planet, two warming paths · 1980–2025

NASA GISS GISTEMP v4 land-ocean temperature index, calendar-year J-D columns from separate Northern and Southern hemisphere tables, accessed 19 October 2026. 46 annual observations per hemisphere, 1980–2025; 92 total. Anomalies in °C relative to each hemisphere’s own 1951–1980 normal, not absolute temperatures: a larger anomaly does not mean one hemisphere is absolutely hotter. In 2025: North +1.47°C, South +0.89°C. Incomplete 2026 is excluded. Historical estimates may be revised. No cumulative transformation, causal claim or assessment of the Paris Agreement’s long-term temperature threshold. Movement between annual observations is visual interpolation, not extra measurements. Exact data and method links are in source notes.

Data: NASA GISS GISTEMP v4, attributed factual annual observations; primary tables and methodology in source notes. Northern marker: NASA Earth Observatory / G.Projector, North pole map, via Wikimedia Commons (Kcida10), public domain in the U.S. Southern marker: Galileo South Polar Projection of Earth, NASA/JPL; an illustrative 24-hour mosaic, not a temperature map. Background: NASA/DSCOVR EPIC, Earth, 6 July 2015, public domain in the U.S.; enlarged and faded in the native chart. Polar markers are separate from the background and identify hemispheres, not temperature measurements. Exact image, NASA conditions and JPL image-use links in source notes. No endorsement implied.