Recorded global surface temperatures have risen steadily over the past decades (NOAA). The question will be suspended on 31 December 2026 if still open and the outcome determined using data published by NOAA, expected in January 2027 (NOAA - Global Time Series, change "Month" to "All Months" and set a relatively recent "Start Year," and click "Plot"). The data for a month as first reported will count, and subsequent revisions to past months are immaterial. As of the launch of this question, the highest reported anomaly was 1.44°C in September 2023.

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