Earth’s temperature has surged in the past two years, and climate scientists will soon announce that it hit a milestone in 2024: rising to more than 1.5 °C above pre-industrial levels. But is this sudden spike just a blip in the climate data, or an early indicator that the planet is heating up at a faster pace than researchers thought?

Some scientists argue that the spike can be mostly explained by two factors. One is the El Niño event that began in mid-2023 — a natural weather pattern in which warm water pools in the eastern tropical Pacific Ocean, often leading to hotter temperatures and more-turbulent weather. The other is a reduction over the past few years in air pollution, which can cool the planet by reflecting sunlight back into space and seeding low-lying clouds. Yet neither explanation fully accounts for the temperature surge, other researchers say.

Some say that the massive temperature spike might end up being a blip in the climate data, owing in large part to new regulations covering air pollution from ocean-going ships… Not everyone is convinced, however. If the pollution reduction was the primary explanation, warmer temperatures should coincide with the areas most frequented by ships… Nor do the numbers necessarily add up.

Soft paywall so see summary above. The two studies cited in the news:

• Goessling, H. F., Rackow, T. & Jung, T. Science https://doi.org/10.1126/science.adq7280 (2024). (about the El Nino effect)
• Gettelman, A. et al. Geophys. Res. Lett. 51, e2024GL109077 (2024). (about the reduction in ship tracks)