Incoming: More wind, heat, and dry air.
Jennifer Rubin’s last column in the Washington Post, just before she quit in disgust with Billionaire owner Jeff Bezos policies.
Jennifer Rubin in the Washington Post:
The hellish fires tearing through the Los Angeles area are a preview of what’s to come if politicians, ideologues and Big Oil continue to ignore climate change. The latest disaster “erupted following a stark shift from wet weather to extremely dry weather — a phenomenon scientists describe as ‘hydroclimate whiplash,’” the Los Angeles Times reported on Thursday. “New research shows these abrupt wet-to-dry and dry-to-wet swings, which can worsen wildfires, flooding and other hazards, are growing more frequent and intense because of human-caused climate change.”
Drenching rains resulting from rising ocean temperatures lead to overgrowth on hillsides, which in abnormally dry weather can catch fire. These “extreme weather swings will continue to become more frequent and volatile, with precipitation increasingly concentrated in shorter, intense bursts, interspersed with more severe dry spells,” the newspaper said.
The data is the data: “In [a] study, published Thursday in the journal Nature Reviews Earth & Environment, the researchers examined global weather records and found that hydroclimate whiplash events have already grown 31% to 66% since the mid-1900s, and are likely to more than double in a scenario in which the world reaches 3 degrees Celsius, or 5.4 degrees Fahrenheit, of warming.”
Hydroclimate volatility refers to sudden, large and/or frequent transitions between very dry and very wet conditions. In this Review, we examine how hydroclimate volatility is anticipated to evolve with anthropogenic warming. Using a metric of ‘hydroclimate whiplash’ based on the Standardized Precipitation Evapotranspiration Index, global-averaged subseasonal (3-month) and interannual (12-month) whiplash have increased by 31–66% and 8–31%, respectively, since the mid-twentieth century. Further increases are anticipated with ongoing warming, including subseasonal increases of 113% and interannual increases of 52% over land areas with 3 °C of warming; these changes are largest at high latitudes and from northern Africa eastward into South Asia.
Extensive evidence links these increases primarily to thermodynamics, namely the rising water-vapour-holding capacity and potential evaporative demand of the atmosphere. Increases in hydroclimate volatility will amplify hazards associated with rapid swings between wet and dry states (including flash floods, wildfires, landslides and disease outbreaks), and could accelerate a water management shift towards co-management of drought and flood risks. A clearer understanding of plausible future trajectories of hydroclimate volatility requires expanded focus on the response of atmospheric circulation to regional and global forcings, as well as land–ocean–atmosphere feedbacks, using large ensemble climate model simulations, storm-resolving high-resolution models and emerging machine learning method
“We’re in a whiplash event now, wet to dry, in Southern California,” said Daniel Swain, a UCLA climate scientist who led the research. “The evidence shows that hydroclimate whiplash has already increased due to global warming, and further warming will bring about even larger increases.”
The extreme weather shift over the last two years in Southern California is one of many such dramatic swings that scientists have documented worldwide in recent years.
Unusually wet winters in 2023 and 2024 nourished the growth of brush and grass on hillsides across the region, and then came the extremely warm and rainless weathersince spring that has left desiccated vegetation throughout the Los Angeles area.
Since October, much of Southern California has baked in record-dry conditions. This extraordinary whiplash in weather has increased risks of the type of extreme wildfires that exploded in strong winds this week, Swain said.