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Environment & Climate

Global sea-surface temperature hits record high in August

Data from the Copernicus agency shows ocean temperatures reached a record daily average amid climate change and an emerging El Niño.

The short version

  • Europe's Earth observation agency Copernicus recorded a global average sea-surface temperature of 70 degrees on August 22, surpassing the previous single-day high set in March 2024.
  • The record comes during August, an atypical month for annual global ocean heat peaks, which historically occur around March and April.
  • Scientists attribute the rising temperatures to long-term human-driven climate change combined with a strong El Niño pattern in the tropical Pacific.
  • Warmer ocean waters threaten marine ecosystems, heighten storm risks, exacerbate sea level rise, and lower the ocean's capacity to absorb carbon dioxide.

Key facts

  • The global average daily sea-surface temperature reached 70 degrees on August 22, setting a new high since record-keeping began in 1979.[Hacker News]
  • The previous single-day record for global average sea-surface temperature was set in March 2024.[Hacker News]
  • Copernicus reports that global ocean temperatures normally peak in March and April following the Austral summer.[Hacker News]
  • Samantha Burgess of the European Center for Medium-Range Weather Forecasts noted that El Niño is introducing heat on top of decades of human-driven warming.[Hacker News]
  • Localized record ocean temperatures have also been measured in the western Mediterranean Sea and near the polar regions.[Hacker News]

What remains uncertain

  • The full extent of how much higher ocean temperatures will rise during the ongoing El Niño event remains to be seen.[Hacker News]

Sources