Bomb Cyclone, Atmospheric River: How Weather Terms Expanded

Californians have been warned in recent months of weather patterns ranging from a “vicious heat dome” to back-to-back “atmospheric rivers” and the ever-worrying “bomb cyclone”.

While it may feel like recent weather has been dominated by a series of new phenomena, experts say these terms and events are well-established in the scientific world, but simply new to much of the general public. .

Many of these weather terms have entered public discourse in recent years due to a combination of factors: more extreme weather in the age of climate change, a new wave of science journalism, and the virality of the internet and social media, which often helps promote such catchy phrases.

“We’re hearing these terms more, and I think it’s partly in reaction to (the fact that) the weather has gotten crazier,” said Jeff Masters, meteorologist and writer for Yale Climate Connections. “(These terms) have been around scientifically for a long time, but they’re dusted off and trotted out here to…capture the edge of what we see.”

James Marshall Shepherd, director of the atmospheric science program at the University of Georgia, also credits a new wave of weather journalism with helping to popularize these more scientific and catchy terms. This includes meteorologists who write for climate-focused websites or in established news outlets, like the Washington Post’s Capital Weather Gang.

“They started extracting some of this terminology from the scientific literature into more popular writing,” Marshall Shepherd said. “These things like the polar vortex and bombogenesis and the atmospheric river and the derecho, each of them has been around for decades, especially in the atmospheric science (and) meteorology literature.”

Most call the development extremely positive, but there are growing concerns that these dramatic terms could be “misused and abused in different circles,” said UCLA climatologist Daniel Swain.

“I think using more colorful language is sometimes helpful from a science communication perspective,” Swain said. “But you have to put things in context.”

The “polar vortex” is a term that several meteorologists cite as often misused, pointing out that it has sometimes been erroneously cited as a developing weather pattern, when referring to an air mass occurring regularly over the Arctic.

To better understand some of these new weather phenomena, Times staff dove into the archives to see how long these phrases made headlines and interviewed experts about their scientific origins and true meaning.

A look at each term:

• Atmospheric river: a concentrated stream of water vapor in the middle and lower levels of the atmosphere that crosses the ocean until an earthly obstacle forces it to expel its moisture.

In the scheme of meteorological terms, the “atmospheric river” is relatively new, being cited in scientific papers only in the past 30 years, Masters said.

He said the phenomenon had been identified as early as 1939, but it wasn’t until 1992 that an article coined the term “tropospheric river”. It then turned into an atmospheric river simply to make the terminology “more accessible,” Masters said.

“Now that we have high-resolution satellites and have flown research aircraft into these atmospheric rivers, we’re really learning a lot more about them than we didn’t know,” Masters said.

Some of these phenomena are often called quick pineapplewhich experts have called a more colloquial term for certain atmospheric rivers that originate near the Hawaiian Islands.

The term “atmospheric river” first appeared in The Times in 1993, in an article centered on the research paper that first named the phenomenon. The phrase didn’t reappear for nearly two decades, when meteorologists and scientists warned in 2011 that California could be vulnerable to them.

A lot has changed in a decade. So far in 2023, the term has appeared in dozens of Times articles.

• Bomb Cyclone; bombogenesis: the rapid intensification of a cyclone or low pressure system; the formation of such a rapid reinforcement system.

The phenomenon was first referred to as a “bombshell” in a 1980 article that focused on rapidly or explosively developing cyclones, according to The Washington Post. Authors have used the word to help express the strength and danger of such storms, but the phenomenon has long been studied by meteorologists.

“Somehow it’s just worked its way into common lingo over the past few years because it’s dramatic and descriptive,” Masters said.

To the public, the term is still relatively new, having only made its way into the Times in 2018, when journalists used both “bomb cyclone” and “bombogenesis” to describe a major storm hitting the northeastern United States.

The phenomenon has been credited with the strong and deadly storm that hit California last week, and Swain said the United States would likely see another such storm soon.

“There are about 40 or 50 quote-bomb cyclones a year in the Northern Hemisphere,” Swain said, but he added that they are more likely to develop over the North Atlantic and in the Gulf of Alaska than off the northern coast of California.

This term jumped into the public consciousness during some particularly cold storms on the East Coast. It was used in a science writer’s post in 2014 and picked up by other outlets. But Masters said the term has been around since the 1930s.

Masters said that term caught the attention of him and his peers because it’s more of a stratospheric phenomenon — in the upper second layer of the atmosphere — so it’s not as relevant on the weather plane, although it may have an effect on Earth’s weather.

“Weather in the stratosphere doesn’t really impact what happens on the ground,” Masters said, explaining why he generally avoids using the term, which he says has been “misused and overrated.” .

The Times first used it in a scientific sense in 1992, describing a trip to the Arctic to study the atmosphere there. It wasn’t until 2014 that it was used in a weather story.

• Heated dome: a more colloquial term that describes a hot, high-pressure system that isn’t moving anytime soon.

Experts said the term isn’t as entrenched in the scientific literature, but it’s still an accurate description of a massive heat wave. some meteorologists said it could also be considered a heat bubble.

“It’s just a big old high-pressure system that’s hot,” Masters said. “You can consider it a dome, why not?”

The term was first used in the context of weather in The Times in 2012, describing a long, hot event in Greenland, melting a massive ice cap. It has been used several times in recent years.

• Supercell thunderstorm: a thunderstorm with a rotating updraft, or updraft, which can cause more extreme weather conditions.

These thunderstorms are among the most intense and organized storms, which can last for several hours and trigger tornadoes or bring hail, an expert said.

“You can go back to textbooks from 50 years ago and see people talking about supercells,” Marshall Shepherd said, calling them “basic meteorology.”

But the term hasn’t been that common in weather reports, only appearing in The Times in 1999, when it was mentioned in a story about a string of tornadoes that swept through Oklahoma and Kansas.

• snow storm: the rare combination of thunder and lightning during a snowstorm.

Although it’s far from a new term, Marshall Shepherd thinks the word likely gained prominence after a Weather Channel meteorologist got flustered while experiencing the phenomenon in Boston. in 2015.

“Snow is very rare,” said Marhsall Shepherd. “It’s not that common to have thunderstorms in a snowy environment.”

It first appeared in The Times in 2007, after a thunderstorm was recorded in Southern California, and has since been increasingly mentioned, including this winter.