In a world getting used to extreme weather, 2023 is starting off wilder than ever, and meteorologists say it’s natural weather weirdness, aided by human-induced climate change.
Experts said much of what is causing problems worldwide is due to the churning Pacific Ocean, which was carried by a choppy jet stream.
At least one highway in drought-stricken California looked more like a river due to heavy rain, technically called a river of atmospheric moisture. As the Northern Hemisphere was warmer than the average at the end of the 20th century by 2.6 degrees (1.4 degrees Celsius) on Wednesday, the New Year brought shirt-sleeve weather to the Eastern United States and record high temperatures to Europe. And that’s after cold air escaped from the Arctic to create a Christmas mess for most of the United States.
“All the supplies are in place for two weeks of wild weather, especially in the western US,” special meteorologist Ryan Maue said in an email.
The big driver, Maue said, was a three-year La Nina—the natural temporary cooling of the equatorial Pacific Ocean that changed the world’s weather—that will never give up. It creates real waves in weather systems that ripple around the world. And in certain parts of the waves, there are storms, called bomb cyclones, where the atmospheric pressure drops low and rapidly, moving over atmospheric waves that are quite wet and carry air called jet streams.
Maue and Woodwell Center for Climate Research climate scientist Jennifer Francis said the jet stream is unusually choppy at the moment. Maue said the storms hit the warm subtropics and “formed a moisture conveyor belt to destroy the West Coast of the United States.”
“I would describe the jet stream and bomb hurricane as a moisture-laden, runaway Pacific freight train,” said Maue, a former chief scientist of the National Oceanic and Atmospheric Administration under the Trump administration. “Climate change adds more fuel to the locomotive engine.”
More than 5 inches of rain fell in the Sacramento area on Saturday, and California prepared for larger storms on Wednesday and Thursday. On Wednesday, snow mass was more than 170% of normal, the third highest in 40 years.
In addition to La Nina, a different natural transient weather event called the Madden-Julian Oscillation is increasing storms in the western Pacific, Maue said.
Francis points to a “drop” of warm seawater in the Aleutian Islands, a more frequent phenomenon and an “insanely hot” Arctic — 5.8 degrees (3.2 degrees Celsius) from Wednesday, 1979-2000 was warmer than average – as part of what enlivens the Pacific.
With a more choppy jet stream than usual, extremes of all kinds go up and down the planet, Francis said.
“You can think of it like a jump rope. When you start tapping on one end, that ripple eventually crosses the entire jump rope,” Francis Wednesday said. “And so maybe this type of waving driving in the Pacific might be accentuating it in Europe as well.”
A weather station in Delémont, Switzerland, on the border with France, broke the January record with an average daily temperature of 18.1 degrees Celsius (about 65 degrees Fahrenheit) on the first day of the year. According to extreme weather tracker Maximiliano Herrera, Tuesday broke the January record with 17.2 degrees Celsius (63 degrees Fahrenheit) in Bucharest, Romania, and 17.9 degrees Celsius (64.2 degrees Fahrenheit) in the Russian Republic of Dagestan.
Swiss weather service MeteoSuisse joked on its blog: “… this turn of the new year can almost make you forget you’re on the cusp of winter.”
Colorado meteorologist Bob Henson of Yale Climate Connections said this extreme weather was “a beacon of hope”, particularly as record heat in Europe in January alleviated winter heating fuel shortages caused by Russia’s invasion of Ukraine. And California, where more than 20 years of mega-drought has worsened wildfires, is getting much-needed rain and snow—a lot, in fact.
Roads and embankments in California were flooded earlier this week. Schools in the San Francisco area were closed on Wednesday as more than 8,000 sandbags were distributed in anticipation of extensive flooding. Flights have been cancelled.
“Excessive precipitation over already saturated soils will cause rapid increases in streams, streams and rivers, as well as flooding in urban areas,” forecasters said in a report.
Victor Gensini, professor of meteorology at Northern Illinois University, said he found nothing unusual except the impressive record temperature in Europe, which is “another example of the manifestation of human-induced climate change.”
Weather Underground co-founder Jeff Masters, currently at Yale Climate Connections, said the weather is inherently extreme “so the recent events we’ve seen could happen naturally.” “However, with the disruption of global weather patterns brought about by climate change, the likelihood of seeing unusual weather events in any given season increases.”
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