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Earth

Weather observations, long-term climate patterns and local conditions operate at different scales.

In practice

When comparing records, keep location, time interval and measurement method together. One unusually warm day does not answer a question about a long-term pattern.

Use the same units and time window before interpreting a change.

Measurements

Measure a spread

4 units between the extremes.

A range describes these observations; it is not measurement uncertainty or a confidence interval.