Over 40 trillion gallons of rain fell on the Southeastern United States due to Hurricane Helene, resulting in catastrophic flooding and over 100 deaths. Meteorologists attribute this unprecedented rainfall to a combination of storm systems and the impacts of climate change, which increases atmospheric moisture capacity.
Recent meteorological assessments indicate that over 40 trillion gallons of rain descended upon the Southeastern United States within the past week, primarily attributed to Hurricane Helene and an accompanying rainstorm. This unprecedented volume of precipitation has astonished experts and can be likened to filling the Dallas Cowboys’ stadium approximately 51,000 times or filling Lake Tahoe once. For illustrative purposes, had this vast quantity of water been concentrated solely on North Carolina, it would result in an accumulation surpassing 3.5 feet (approximately 1 meter) in depth, enough to fill over 60 million Olympic-sized swimming pools. Ed Clark, the head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama, remarked on the extraordinary nature of this rainfall: “That is an astronomical amount of precipitation. I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.” The aftermath of this deluge has been catastrophic, resulting in over 100 fatalities, as reported by officials. Private meteorologist Ryan Maue, employing satellite data and ground observations, computed that this rainfall amounted to 40 trillion gallons, with 20 trillion gallons impacting primarily Georgia, Tennessee, the Carolinas, and Florida due to Hurricane Helene. Clark independently confirmed this estimation, suggesting it might even be a conservative figure, with additional rain potentially recorded in Virginia. To illustrate the enormity of this precipitation, consider that it exceeds more than twice the water capacity held by key reservoirs in the Colorado River Basin, namely Lake Powell and Lake Mead. The exceptional rainfall resulted from a combination of several storm systems. Prior to the impacts of Helene, the Southeast had already been experiencing heavy rainfall due to a stalled low-pressure system that had severed from the jet stream. This situation funneled warm moisture from the Gulf of Mexico, while a near-storm system along North Carolina’s coast contributed as much as 20 inches of rain, according to North Carolina state climatologist Kathie Dello. Adding to this was Hurricane Helene, described as one of the most considerable storms in recent decades, which was rich in moisture and progressed rapidly toward the Appalachians. Kristen Corbosiero from the University of Albany noted, “It was not just a perfect storm, but it was a combination of multiple storms that led to the enormous amount of rain. That collected at high elevation, we’re talking 3,000 to 6,000 feet. And when you drop trillions of gallons on a mountain, that has to go down.” The mountainous terrain exacerbated the flooding issues, intensifying both runoff and moisture extraction from the atmosphere, as emphasized by Clark, Maue, and Corbosiero. North Carolina officials reported an astonishing maximum rainfall of 31.33 inches in the small community of Busick, with Mount Mitchell recording over two feet. Reflecting on the increasing trend of extreme rainfall events, Clark stated, “Before 2017’s Hurricane Harvey, I never thought in my career that we would measure rainfall in feet. After disasters such as Harvey and Florence, we now see events occurring yearly where rainfall is measured in feet.” In relation to climate change, several meteorologists, including Corbosiero and Dello, have noted an increase in precipitation associated with higher global temperatures, which allows the atmosphere to retain approximately 4% more moisture for each degree Fahrenheit of warming. In preliminary analyses conducted by scientists at Lawrence Berkeley National Lab, it was concluded that climate change may have contributed to an increase of up to 50% in rainfall during Helene across certain regions of Georgia and the Carolinas. Dello remarked that the impacts of climate change in these events are evident: “We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. There was a time when a tropical storm would have caused some rain and damage, but not apocalyptic destruction.”
The article reports on the unprecedented amount of rainfall experienced in the Southeastern United States due to Hurricane Helene and an associated rainstorm. It highlights the alarming volume of more than 40 trillion gallons of water and the subsequent devastating consequences, such as fatalities and significant flood damage. Meteorologists emphasize the rarity of such extreme weather events and their potential connection to climate change, elucidating the mechanics behind these storms and the increasing trend of heavy precipitation.
In summary, the recent rainfall in the Southeastern United States, attributed to Hurricane Helene and preceding storms, amounted to over 40 trillion gallons, resulting in catastrophic flooding and extensive damage. Meteorologists stress that these unprecedented weather events may be exacerbated by climate change, which enables the atmosphere to hold more moisture, thus leading to more extreme precipitation incidents. Continuous monitoring and further research are necessary to fully understand the implications of such climatic phenomena.
Original Source: abcnews.go.com
