Air-sea interactions triggered and prolonged the 2013-2016 North

A new study links the 2013–2016 North Pacific marine heatwave—better known as the “Blob”—to a prolonged two-way coupling between the atmosphere and the ocean. Researchers W. Jiang, G. Forget, Y. Song and colleagues say the warming wasn’t driven by a single burst of atmospheric heating or one ocean-current anomaly. Instead, unusual warmth was reinforced across a vast Pacific region through feedbacks that both initiated and prevented the event from collapsing quickly. Persistent high pressure reduced clouds and weakened winds, boosting solar heating and limiting vertical mixing. Weaker conditions also reduced evaporative cooling and helped trap heat near the surface, while the ocean’s warming sustained the atmospheric pattern.