Explore the evidence

Choose a place, temperature or rainfall, and a period to build a question about historical change. Read the observations and their coverage before fitting a trend.

No account is needed to read observations or run Trend Check. Signing in is optional and only needed for sealed investigations that follow you across devices. A historical trend does not establish causation or predict future climate.

Continue exploring

• City predictions: weather, climate and renewable resources
• Privacy
• Find the change. Test the evidence.
• Trend Check: is it really changing?
• Global climate atlas
• How the analysis works
• Data sources
• Space Apps 2026: Be an Earth System Trend Detective
• Earth Pulse: where is our planet changing?
• Ground check: does NASA's record match a real thermometer?
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• Future Cities: 20 cities toward 2050 in 3D