What caused an unexpected, record-breaking tidal event off the east coast of China?

Late Monday night, along the coast of the Bohai Sea in northeast China, the water began to rise as it normally does when the tide rises.

But the water continued to rise.

Under the cover of darkness, the tide swept across several coastal regions in Liaoning and Hebei provinces, as well as the city of Tianjin, which is situated just over 100 km (62 miles) southeast of the capital Beijing. The waters quickly flooded inland areas, triggering emergency responses and breaking official records.

“In the absence of obvious winds and waves, a sudden rise in water levels over such a large area has never been recorded, either nationally or internationally,” said Fu Cifu, head of the Storm Forecast Office at the National Center for Marine Environmental Prediction. , in an interview with state news agency Xinhua on Tuesday.