Updated Jun 5, 2024 - Energy & Environment

Global heat record broken for 12th straight month in May

Line chart showing how 2024 global surface air temperature anomalies have far exceeded 1940-2023 anomalies compared to the preindustrial average. The anomaly was +1.66°C in January 2024, +1.77°C in February 2024 and +1.60°C in May 2024. June 2023 to May 2024 were the hottest 12 months on record with May reaching +1.52°C.
Data: ERA5; Chart: Tory Lysik/Axios Visuals

May was the 12th consecutive month to set a monthly global average temperature record, and exceed a key Paris Agreement temperature target.

Why it matters: The new data comes amid a slew of findings from climate monitoring groups released Wednesday, timed to coincide with a speech in New York by U.N. Secretary-General António Guterres.

  • This is not the longest period on record of warmest months (that stands at 15 months). However, it is the longest streak of months to reach or exceed the Paris Agreement's aspirational target of limiting global warming to as low as 1.5-degrees compared to preindustrial levels.

The big picture: The news comes as parts of Asia, Mexico and Central America, and now the Southwestern U.S. have baked from withering heat waves, with all-time high temperature records set across the world.

  • It also comes as actions to limit climate change has been crowded out on the international agenda amid geopolitical strife, economic concerns, multiple elections and other factors.
  • Upcoming G20 and G7 meetings loom large to generate momentum on major agenda items, like generating far more climate finance, leading up to COP29 in November.

Zoom in: According to the European Commission's Copernicus Climate Change Service, May's global average surface temperature came in at 1.52°C (2.73°F) above preindustrial levels.

  • This year has featured temporary leaps above the 1.5-degree target, beyond which the effects of global warming could spell the demise of low-lying island nations, and other highly vulnerable regions.
  • Long-term warming that exceeds 1.5°C would also bring far more significant, and potentially catastrophic, consequences even to wealthier developed nations, studies have shown. Those effects include more rapid and sharper sea level rise, deadly extreme weather events and other impacts.

Yes, but: The 11 months in a row that tied or broke the 1.5°C barrier did not yet constitute a breaching of the Paris target, since the benchmark refers to a timescale of multiple decades.

  • Still, the fact that the climate is now exceeding the target with greater regularity, and is projected to continue doing so, is a sign of the matter's urgency.
  • In fact, Guterres noted in his speech that one of the reports released Wednesday finds that due to a rapidly depleting carbon budget, countries may have as few as five years at today's emissions levels before they guarantee the target will be exceeded on a long-term basis.

By the numbers: Guterres also made his comments as a World Meteorological Organization report, along with the UK Met Office, projected that during the next five years, there is an 80% likelihood that at least one year will feature a global average temperatures at or above 1.5°C compared to preindustrial levels.

  • As recently as 2015, the same organizations declared there was a "close to zero" chance of one of the subsequent five years exceeding the 1.5*C benchmark, the report notes.

What they're saying: "It is shocking but not surprising that we have reached this 12-month streak," said Carlo Buontempo, director of the Copernicus Climate Change Service, in a statement.

  • "While this sequence of record-breaking months will eventually be interrupted, the overall signature of climate change remains and there is no sign in sight of a change in such a trend."
  • Guterres, in his speech grounded in the new data, stated: "Our planet is trying to tell us something. But we don't seem to be listening."
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