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Bomb Cyclone

New Year’s Eve storm over the Aleutians; Image credit: CIRA/NOAA

The Aleutian Chain was rocked by an incredible storm over New Years. The wonderfully named Bomb Cyclone, set a record in Alaska for a low pressure system.

High and low-pressure systems form when air mass and temperature differences between the surface of the Earth, and the upper atmosphere, create vertical currents. In a low pressure system, the air currents flow upward, sucking air away from the earth’s surface like a giant Shop*Vac.

Eareckson Air Force Base on Shemya Island recorded the record low pressure at 924.8 millibars.

The record breaking low pressure system; Image credit: Tomer Burg

A sea buoy off of Amchitka Island, registered a wave at 58.1 feet. Winds at Shemya hit gusts of 83 mph. This was an impressive storm that pummeled the outer islands of the Aleutian Chain. From Atka to Adak, the islands were seeing 40-50 foot waves and hurricane force winds.

Graphic credit: National Weather Service – Fairbanks

St Lawrence Island and the Yukon Delta saw high winds and blizzard conditions when the storm hit Alaska’s mainland.

Unlike a hurricane, which extract heat from the ocean, as they grow in power, a maritime cyclone creates energy by drawing together warm and cold air masses. It’s the energy created when the warm air rises and the cold air sinks, that gives rise to the cyclone.

Sources: NOAA, UAF, NWS, NASA