You’ve probably heard about atmospheric rivers. These are vast flowing streams of water vapor in Earth’s atmosphere. They are responsible for summer heatwaves and unseasonably warm winters.
According to the title of an article published 19 December 2024 in IFL Science, Atmospheric Rivers Are Influencing Unseasonably Warm Winters And Heatwaves. Here’s the lede: “Atmospheric rivers – vast flowing streams of water vapor that flow high up in Earth’s atmosphere – appear to fuel sweaty heatwaves in summer, as well as unseasonable warm weather in the winter, according to a new study.” The “new study” was conducted by two scholars at Yale University and published as an open-access paper in the renowned peer-reviewed journal, Nature, on 18 December 2024.
The following two paragraphs at IFL Science explain with an example: “The phenomenon of atmospheric rivers is closely associated with rainfall because they shift huge amounts of water vapor from the seas to over land where it’s dumped as precipitation. One of the best-known examples is the Pineapple Express, a powerful atmospheric river that often transports moisture from the tropical Pacific near Hawaii to the West Coast of the United States and Canada, causing downpours of rain.
The impact on moisture and precipitation has been well studied, but scientists at Yale University have now investigated how atmospheric rivers may be associated with heat.”
Atmospheric rivers occur naturally. They have always been part of Earth’s weather and therefore Earth’s climate. However, the issue of concern in this case is the recent increase in global average temperatures driven by increased burning of fossil fuels. According to the article in IFL Science, warming global temperatures resulting from greenhouse gas emissions are causing an increase in the size, frequency, and intensity of atmospheric rivers. Spikes in temperature were related to atmospheric rivers at hourly and daily timescales. According to the lead author of the peer-reviewed paper: “There was no doubt – atmospheric rivers are really impactful for both timescales.”
Atmospheric rivers typically influence the heat energy on the surface of the Earth in two ways. First, they transport warm air from one region to another. Second, the presence of moisture creates a heavy blanket of clouds. These clouds retain heat close to Earth’s surface. The co-author of the peer-reviewed, open-access paper explains in the article at IFL Science: “We’re seeing temperature anomalies associated with atmospheric rivers that are 5 to 10 degrees Celsius higher than the climatological mean. The numbers are astounding.” Five to 10 degrees Celsius is 9 to 18 degrees Fahrenheit. That’s a huge increase relative to the “climatological mean,” or average.
I now turn to the peer-reviewed, open-access paper in the renowned journal, Nature. Titled Atmospheric rivers cause warm winters and extreme heat events, the paper was published 18 December 2024. The Abstract tells the story while quoting abundant peer-reviewed evidence: “Atmospheric rivers are narrow regions of intense water vapour transport in the Earth’s atmosphere. These transient phenomena carry water from the subtropics to the mid-latitudes and polar regions, making up the majority of polewards moisture transport and exerting control on the precipitation and water resources in many regions. In addition to transporting moisture, atmospheric rivers also transport heat, but the impact of this transport on global near-surface air temperatures has not yet been characterized. Here we show that seasons with more frequent atmospheric rivers also have warmer than average temperatures in many mid-latitude regions, and that atmospheric river events are associated with temperature anomalies of 5–10 °C above the climatological mean. This is due to anomalous horizontal transport and convergence of sensible heat and moisture in the lower atmosphere, which increases both downward sensible heat flux and downwelling long-wave radiation at the surface. On an hourly timescale, over 70% of extreme warm-temperature anomalies occur within atmospheric rivers in large portions of the mid-latitudes, and atmospheric rivers are associated with moist and compound heatwaves in many regions worldwide, suggesting that consideration of atmospheric rivers may improve predictive capability for certain extreme heat events. Our results demonstrate that atmospheric rivers significantly impact air temperatures on a wide array of timescales, and that they may play a wider role in global energy transport than previously recognized.”
I’d like to draw your attention to two key points in the Abstract: (1) Atmospheric rivers account for the majority of moisture transported from the subtropics to the mid-latitudes and polar regions, thus exerting control on the precipitation and water availability in many regions; and (2) atmospheric rivers also transport heat, but the impact of this transport on global near-surface air temperatures was not characterized before now. This recent study demonstrates that seasons with more frequent atmospheric rivers also have warmer-than-average temperatures in many mid-latitude regions, which is critical to understanding Earth’s energy imbalance. In addition, this study shows that atmospheric rivers are associated with temperature anomalies of 5–10 °C above the climatological mean. This is a tremendous increase in above-average temperature.
As I have explained repeatedly in this space, the rate of environmental change underlies the ability of biological entities to survive. This includes populations, communities, and species. If the environment changes too quickly, species are driven to extinction. As pointed out by the designed-to-fail Intergovernmental Panel on Climate Change in its 8 October 2018 report, Global Warming of 1.5°, Earth is amid the most rapid event in planetary history. This does not bode well for life on Earth, including the continued existence of humans.
Author
"Dr. Guy McPherson is an internationally recognized speaker, award-winning scientist, and the world’s leading authority on abrupt climate change leading to near-term human extinction. He is professor emeritus at the University of Arizona, where he taught and conducted research for twenty years. His published works include 14 books and hundreds of scholarly articles. Dr. McPherson has been featured on TV and radio and in several documentary films. He is a blogger, cultural critic, and co-host of his own radio show “Nature Bats Last.” Dr. McPherson speaks to general audiences across the globe, and to scientists, students, educators, and not-for-profit and business leaders who seek their best available options when confronting Earth’s cataclysmic changes." source
Latest Peer-Reviewed Journal Article: McPherson, Guy R., Beril Sirmack, and Ricardo Vinuesa. March 2022. Environmental thresholds for mass-extinction events. Results in Engineering (2022), doi: https://doi.org/10.1016/j.rineng.2022.100342.
