Satellite Images Capture Huge Atmospheric River Sweeping Over Alaska and Canada

NASA’s Earth Observatory released immoderate arresting images of the atmospheric stream that swept done the Gulf of Alaska earlier this week.

The images amusement the river—an airborne corridor of moisture that carries with it ample amounts of rain—stretching from the Pacific Ocean to the coasts of Alaska, British Columbia, and Yukon. According to NASA’s Global Hydrometeorology Resource Council, atmospheric rivers are greater than 1,245 miles (2,000 kilometers) agelong and little than 620 miles (1,000 km) wide. In different words, astir a stream shape, but successful the air. The improvement often occurs successful the extratropical northbound Pacific; past year, swaths of California were beset by utmost rainfall and snowstorms owed to an atmospheric river.

However, this peculiar stream was “uncommonly strong,” according to an Earth Observatory release. In the images, taken connected September 22 by the Suomi NPP Satellite’s Visible Infrared Imaging Radiometer Suite, the stream extends from the Pacific coastline acold retired to sea. In Bella Bella, British Columbia, betwixt 2 to 4 inches of rainfall fell regular from September 21 to 24. Towns successful southeast Alaska experienced akin amounts of rainfall.

Another representation of the stream was snapped connected September 24 by NASA’s Earth Polychromatic Imaging Camera (or EPIC) connected the Deep Space Climate Observatory satellite, known arsenic DSCOVR. Taken astir 1 cardinal miles supra Earth, the representation intelligibly shows the stream connected an adjacent larger standard than the featured apical image.

Also successful that representation (in the bottom-right-hand corner) is Hurricane Helene—currently wreaking havoc from confederate Florida done North Carolina—when it was inactive a tropical storm. Hurricane Helene made landfall arsenic a Category 4 tempest and is causing devastating flooding crossed the American southeast. The atmospheric stream successful the northwest is simply a Category 5—the highest tier connected the scale—though its strength was adjacent higher earlier it made landfall.

The atmospheric river, with tropical tempest Helene astatine bottommost right. NASA Earth Observatory images by Michala Garrison, utilizing VIIRS information from NASA EOSDIS LANCE, GIBS/Worldview, and the Suomi National Polar-orbiting Partnership and information from DSCOVR EPIC.

Researchers astatine the University of California, San Diego’s Center for Western Weather and Water Extremes determined that the storm’s integrated h2o vapor transport (IVT), a measurement of atmospheric moisture contented and upwind speeds, were precise precocious compared to different atmospheric rivers successful the country implicit the past 23 years.

“The extremity of the Gulf of Alaska atmospheric stream IVT is remarkable,” said Bin Guan, an atmospheric idiosyncratic astatine NASA’s Jet Propulsion Laboratory and the University of California, Los Angeles, successful the aforesaid release. “This could beryllium 1 of the conditions that perchance contributed to this exceptionally beardown atmospheric stream event.”

The atmospheric stream did not origin important flooding connected the Pacific coast, according to a National Oceanic and Atmospheric Administration tool run by the Office of Water Prediction. The aforesaid could not beryllium said for immense stretches of the southeastern United States—a patchwork of yellow, orange, red, and purple flood alerts arsenic of midday Friday.