A 400-mile-long layer of fog has blanketed California’s Central Valley for weeks. Scientists and meteorologists say the conditions for such persistent cloud cover are in place: an early wet season, cool temperatures, and a stable, immobile high-pressure system.
But take a stroll through X, Instagram, or TikTok, and you’ll see that not everyone is so optimistic.
People have reported that the fog has a strange consistency and is full of black and white particles that don’t look normal. They call it “fuzzy” and stress the name “radioactive” haze, which is the scientific description for such natural haze events – not an indication that they carry radioactive material.
User His finger comes covered in white.
“What’s this-here?” The man says as the camera zooms in on his finger. “There’s something in the fog that I can’t explain… You’re all sure… You’re crazy… What’s going on? They put asbestos in there.”
Another user, @wesleybrennan87, posted a photo of two planes crossing the sky through a break in the fog.
“For anyone following the dense Tule (radiation) fog in California Valley, it lifted for a moment today, only to see that it was very active above our heads…” the user posted.
Scientists confirm the presence of objects in the fog. But what it is and where it comes from, as they say, is disappointingly ordinary.
The Central Valley is known to have some of the worst air pollution in the country.
“Fog is very susceptible to pollutants,” said Peter Weiss-Penzias, a fog researcher at the University of California, Santa Cruz.
“Fog droplets have a large surface area and remain suspended in the air for a long time – days or even weeks – so during that period water droplets can absorb a disproportionate amount of gases and particles, which are known as pollutants,” he added.
He said that although he did not do any analysis of the Central Valley fog during this recent event, it is not difficult to imagine what could be lurking in the droplets.
“It can be a whole alphabet soup of different things. With all the agriculture in this area, the industry, the cars, the wood smoke, there’s a whole bunch” of contenders, Weiss-Penzias said.
He said reports that the fog turns into a gelatinous substance when left behind isn’t entirely surprising, considering all the airborne biological material — fungal spores, nutrients and algae — floating around that can also stick to the Velcro-like water droplets.
The good news, he said, is that although the main route people are exposed to the substance is through inhalation, the fog droplets are relatively large. This means that when they are inhaled, they will not go deep into the lungs, not like the particles we inhale during sunny, dry days. These things can get into your lung tissue.
He added that the biggest concern is ingestion, as fog covers plants or open water tanks.
So make sure to wash your vegetables and anything you leave out that you might wash later.
Dennis Balducci, a fog researcher at the University of California, Berkeley, agreed with Weiss Penzias’ assessment, saying that a storm system expected to move in this weekend will likely push the fog outward and free the valley of its cold, dirty shawl.
But if the high pressure system returns in the coming weeks, we wouldn’t be surprised to see the area covered in fog again.