What’s the Pineapple Categorical?

Animation of an AR event in January 2017 (Credit: NOAA/ESRL/PSD)

This animation from NOAA’s Earth System Analysis Laboratory reveals an atmospheric river occasion in January 2017. Atmospheric rivers are comparatively slim areas within the ambiance which can be chargeable for many of the horizontal transport of water vapor outdoors of the tropics.

Atmospheric rivers are slim areas within the ambiance that transport a lot of the moisture from the tropics to northern latitudes. Atmospheric rivers are a part of the Earth’s ocean water cycle, and are tied carefully to each water provide and flood dangers.

A widely known instance of a robust atmospheric river known as the “Pineapple Categorical” as a result of moisture builds up within the tropical Pacific round Hawaii and may wallop the U.S. and Canada’s West Coasts with heavy rainfall and snow.

Prevailing winds cross over heat bands of tropical water vapor to type this “river,” which travels throughout the Pacific as a part of the worldwide conveyor belt. When it reaches the west coast, the Pineapple Categorical can dump as a lot as 5 inches of rain on California in someday. 

Atmospheric rivers are available all styles and sizes, however those who comprise the biggest quantities of water vapor and the strongest winds are chargeable for excessive rainfall and subsequent flooding. These occasions can have an effect on the complete west coast of North America, usually disrupting journey and damaging property within the course of.

After all, not all atmospheric rivers are disruptive. Many are weak and supply useful rain or high-elevation snow that present essential inputs to the water provides of western communities.