The Southeastern United States experienced over 40 trillion gallons of rainfall from Hurricane Helene and a preceding rainstorm, causing significant flooding and over 100 fatalities. Measurement estimates indicate the rainfall could fill the Dallas Cowboys’ stadium 51,000 times. Experts attribute the unprecedented precipitation amounts to a combination of storm systems exacerbated by climate change, highlighting a concerning trend in increasingly severe weather events.
In the past week, the Southeastern United States experienced unprecedented rainfall totaling over 40 trillion gallons due to the combined effects of Hurricane Helene and an accompanying rainstorm. This astounding volume of water is sufficient to fill the Dallas Cowboys’ AT&T Stadium 51,000 times or completely fill Lake Tahoe once. Should this rainfall be confined to North Carolina alone, it would equate to a depth of 3.5 feet (over 1 meter). The amount of water can be likened to filling more than 60 million Olympic-sized swimming pools. Ed Clark, the head of the National Oceanic and Atmospheric Administration’s National Water Center, remarked, “That’s 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 in extent and the sheer volume of water that fell from the sky.” Meteorologists are alarmed by the devastating flood damage, with reports indicating over 100 fatalities linked to the heavy rainfall. Private meteorologist Ryan Maue, a former chief scientist at NOAA, estimated the volume of rain, using advanced measurements sourced from 2.5-mile grids monitored by satellites and ground observations. He calculated that 40 trillion gallons fell over the eastern United States, with approximately 20 trillion gallons impacting Georgia, Tennessee, the Carolinas, and Florida specifically as a result of Hurricane Helene. Clark confirmed Maue’s calculations, suggesting that the figure of 40 trillion gallons (151 trillion liters) was conservative, hinting at the possibility of an additional 1 to 2 trillion gallons falling, particularly in Virginia. To contextualize this amount of rainfall, Clark highlighted that it exceeds the combined water capacity of the significant reservoirs in the Colorado River basin, namely Lake Powell and Lake Mead. The unfortunate meteorological phenomenon resulted from a convergence of two or three storm systems. Prior to Helene’s arrival, a low pressure system stagnated over the Southeast, drawing in warm water from the Gulf of Mexico, consequently leading to several days of heavy rainfall. An accompanying storm, which did not receive a named status, contributed by unleashing as much as 20 inches of rain along North Carolina’s Atlantic coast, as noted by North Carolina state climatologist Kathie Dello. Moreover, Helene was categorized as one of the most substantial storms in recent decades, retaining significant moisture due to its youthful stage and rapid movement before impacting higher terrains such as the Appalachians, remarked Kristen Corbosiero, a hurricane expert at the University of Albany. Maue articulated that the resultant phenomenon was not merely a singularly perfect storm but rather a combination that led to the deluge, particularly at elevations between 3,000 and 6,000 feet, which amplified the runoff effect. North Carolina officials reported a maximum rainfall measurement of 31.33 inches in the small town of Busick, with Mount Mitchell receiving upwards of 2 feet. Clark reflected on his career observations, stating that prior to 2017’s Hurricane Harvey, he never envisioned measuring rainfall in feet, a pattern which has unfortunately surfaced recurrently in subsequent disasters. The implications of climate change on storm patterns were addressed; Corbosiero and Dello indicated that as the climate evolves, storms are becoming increasingly moisture-laden. A physical principle states that for each degree Fahrenheit increase in temperature, the atmosphere can hold approximately 4% more moisture, with the world having warmed over 2 degrees Fahrenheit since pre-industrial times. Corbosiero noted ongoing discussions among meteorologists concerning the contributions of climate change to the severity of Helene’s rainfall, with preliminary assessments attributing a 50% increase in rainfall to climate change influences in specific regions of Georgia and the Carolinas. Dello asserted, “We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction.”
The article discusses the unprecedented rainfall caused by Hurricane Helene and an associated rainstorm that significantly impacted the Southeastern United States, particularly focusing on the extraordinary amount of precipitation measured, the resultant flooding, and potential links to climate change. It highlights the devastation caused by heavy rains, which resulted in numerous fatalities and remarkable rainfall measurement records. Experts provide insights into the meteorological conditions leading to such intense weather, relating them to longer-term changes in storm behaviors attributed to climate change.
In summary, the severe rainfall exceeding 40 trillion gallons across the Southeast, specifically highlighted by Hurricane Helene’s impact, represents an alarming environmental phenomenon. The sheer scale and geographical extent of the precipitation, as well as the resulting catastrophic flooding, underscore a concerning trend in increasing storm intensity and moisture retention linked to climate change. The reflections of experts and the provided measurements illustrate the urgent need for continued monitoring and adaptation in response to changing climate patterns. Future preparedness measures must take into account the increased likelihood of such extreme weather events.
Original Source: www.pbs.org
