An Introduction To Atmospheric Rivers
Atmospheric rivers are powerful weather events that can move large amounts of moisture from the tropics to other parts of the world. They are composed of narrow bands of water vapor and can span thousands of miles in length. They were first discovered in the early 1990s by Dr. Marty Ralph and since then, have been studied extensively. In this article, we will discuss the basics of atmospheric rivers, including how much moisture they can move, where they happen, how much rain or snow falls during an event and some of the more memorable atmospheric river events in history. We will also look at the potential dangers of atmospheric rivers, what NOAA has to say about them, and if meteorologists can predict them.
What is an Atmospheric River, and Who Discovered It?
Atmospheric rivers are narrow bands of water vapor that can span thousands of kilometers in length and carry large amounts of moisture from the tropics to other parts of the world. They were first discovered in the early 1990s by Dr. Marty Ralph, a professor of atmospheric science at the University of California, San Diego. Since then, atmospheric rivers have been studied extensively, and a better understanding of their formation and behavior has been developed.
How do atmospheric rivers form?
Atmospheric rivers have become a well-known term for describing corridors of intense water vapor transport in the troposphere. In satellite imagery, these corridors are typically viewed as filaments of enhanced water vapor extending from the subtropics to the extratropics, and the associated precipitation can often cause high-impact flooding. Although the exact formation mechanism of these filaments is still a subject of debate, a new study has provided some insight.
Through an analysis of wintertime North Atlantic extratropical cyclones, the study has determined that these filaments of enhanced water vapor are formed by the cold front in the warm sector of the cyclone as it catches up with the warm front. This results in a narrowband of high water vapor content forming ahead of the cold front at the base of the warm conveyor belt airflow. This indicates that the water vapor originates from the cyclone’s warm sector, and not from long-distance transport of water vapor from the subtropics, as previously thought. Furthermore, moisture convergence within the cyclone replenishes water vapor lost via precipitation, allowing for a continuous cycle of evaporation. Therefore, rather than being a direct and continuous feed of moist air from the subtropics, atmospheric rivers are actually the footprints left
How Much Moisture Can Atmospheric Rivers Move?
Atmospheric rivers can move more water than the Amazon River, the world’s largest river. One atmospheric river can transport an estimated 7.5 trillion gallons of water, or enough to fill 11 million Olympic-sized swimming pools.
Where Do Atmospheric Rivers Happen?
Atmospheric rivers are most common in the western United States and can occur in other areas of the world, such as Europe, South America, and Australia.
How Much Rain (or Snow) Falls During an Atmospheric River Event?
Atmospheric rivers can bring large amounts of rain or snow during a single event, which can lead to flooding, mudslides, and other disasters. In some areas, an atmospheric river event can bring more than 10 inches of rain in a 24-hour period.
Name Some History Atmospheric River Events
Some of the more memorable atmospheric river events in history include the Great Flood of 1862 in California, the 1995-96 “Pineapple Express” in the Pacific Northwest, and the 1997-98 El Niño in California.
Are Atmospheric Rivers Dangerous?
Atmospheric rivers can be dangerous and can lead to flooding, mudslides, and other disasters. They can also cause drought in areas where they move moisture away.
What Does NOAA Write About Atmospheric Rivers?
The National Oceanic and Atmospheric Administration (NOAA) states that atmospheric rivers are “the primary driver of extreme precipitation along the West Coast and in other areas of the world, such as Europe, South America, and Australia.” They also note that “Atmospheric rivers are capable of transporting large amounts of water vapor from the tropics to other parts of the world, which can lead to extreme events.”
Can Meteorologists Predict Atmospheric River Events?
Meteorologists can forecast atmospheric river events and can provide warnings of potential flooding and other dangers. They use satellite imagery, computer models, and other tools to monitor atmospheric rivers and provide forecasts.
Conclusion about Atmospheric Rivers
Atmospheric rivers are powerful weather events that can move large amounts of moisture from the tropics to other parts of the world. They were first discovered in the early 1990s and since then, they have been studied extensively. They can bring large amounts of rain or snow and can lead to flooding, mudslides, and other disasters. Not only that, but they can also cause drought in areas where they move moisture away. NOAA states that atmospheric rivers are “the primary driver of extreme precipitation” and meteorologists can use satellite imagery, computer models, and other tools to monitor and predict atmospheric river events.
