Massive Atmospheric River Depicted in Satellite Imagery, Affecting Alaska and Canada
This past week, NASA's Earth Observatory shared awe-inspiring images of an atmospheric river that swept through the Gulf of Alaska. This airborne corridor of moisture stretches from the Pacific Ocean to the coasts of Alaska, British Columbia, and Yukon, carrying immense amounts of rain.
Atmospheric rivers, which are greater than 1,245 miles (2,000 kilometers) long and less than 620 miles (1,000 km) wide, typically occur in the extratropical north Pacific. Last year, California endured extreme rainfall and snowstorms due to an atmospheric river.
NASA’s Global Hydrometeorology Resource Council, atmospheric rivers are greater than 1,245 miles (2,000 kilometers) long and less than 620 miles (1,000 km) wide. In other words, roughly a river shape, but in the air. The phenomenon often occurs in the extratropical north Pacific; last year, swaths of California were beset by extreme rainfall and snowstorms due to an atmospheric river.
However, this specific event was "uncommonly strong," as stated in an Earth Observatory release. The images, captured on September 22 by the Suomi NPP Satellite's Visible Infrared Imaging Radiometer Suite, display the river extending far out to sea. The town of Bella Bella, British Columbia, experienced daily rainfall of two to four inches from September 21 to 24, while towns in southeast Alaska experienced similar amounts.
release. In the images, taken on September 22 by the Suomi NPP Satellite’s Visible Infrared Imaging Radiometer Suite, the river extends from the Pacific coastline far out to sea. In Bella Bella, British Columbia, between two to four inches of rain fell daily from September 21 to 24. Towns in southeast Alaska experienced similar amounts of rainfall.
Another image was taken by NASA's Earth Polychromatic Imaging Camera (or EPIC) on the Deep Space Climate Observatory satellite, also known as DSCOVR, which revealed the river on a larger scale. The image also showcased Hurricane Helene as a tropical storm, still causing havoc in southern Florida through North Carolina, and about to make landfall as a Category 4 storm.
Interestingly, this atmospheric river was a Category 5, the highest tier on the scale. Though its intensity was even higher before it made landfall. Researchers at the University of California, San Diego’s Center for Western Weather and Water Extremes determined that the storm's integrated water vapor transport (IVT), a measurement of atmospheric moisture content and wind speeds, was unusually high compared to other atmospheric rivers in the area over the past 23 years.
did not cause significant flooding on the Pacific coast,
Despite its strength, the atmospheric river did not lead to significant flooding on the Pacific coast, as reported by a National Oceanic and Atmospheric Administration tool. However, vast stretches of the southeastern United States were swamped with flood alerts by midday Friday.
according to a National Oceanic and Atmospheric Administration tool run by the Office of Water Prediction. The same could not be said for vast stretches of the southeastern United States—a patchwork of yellow, orange, red, and purple flood alerts as of midday Friday.
Sources:1. NASA2. National Weather Service3. USGS Water Resources Research Center4. Weather Network
Atmospheric rivers are powerful phenomena that can transport massive amounts of water vapor across the atmosphere, leading to heavy precipitation and flooding. The integrated water vapor transport (IVT) is a vital diagnostic tool for atmospheric rivers, which can have significant social, economic, and environmental impacts on the affected areas.
- In the future, advancements in earth-science technology might lead to more accurate predictions and mitigation strategies for atmospheric rivers, reducing their impact on coastal areas.
- NASA's Global Hydrometeorology Resource Council provides resources and research on atmospheric rivers, including the importance of IVT in understanding their strength and behavior.
- The href link to NASA's Earth Observatory release provides detailed information about the uncommonly strong atmospheric river, including its path and impact on various locations.
- The atmospheric river event of 2024, if it were to occur, could potentially affect river systems and floodplains, requiring careful monitoring and preparation by local authorities and residents.