気候科学：記録的な海洋温度が気候モデルに合致するかもしれない

The large increase in sea surface temperatures in 2023/24 was anomalous, but not completely unexpected when applying climate models, according to research in Nature. The findings suggest that global warming may not have accelerated unexpectedly, as initially feared, but still indicate that the jump in temperature is likely caused by human-driven climate change.

In 2023/24, global sea surface temperatures reached record highs, breaking previous records by around 0.25 °C. This sudden increase raised concerns about whether global warming might have accelerated and whether our current climate models paint an accurate picture of the climate system. To address these questions, Jens Terhaar and colleagues use observation-based statistical models to determine the likelihood of such sea surface temperature spikes within the current understanding of climate patterns.

The models demonstrate that the jump in sea surface temperatures in 2023/24 was a 1-in-512-year event, relative to current warming trends. This result means that the event was not entirely unexpected. However, such an anomaly would have been practically impossible without a global warming trend, the authors note. They add that surface ocean temperatures are expected to revert to the long-term warming trend after such jumps, predicted to happen by September 2025.

The accurate simulation of the 2023/24 anomalous sea surface temperature event indicates that current climate models are fit for purpose, the authors conclude.