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Heat wave or heat dome? Yes, there's a difference

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Heat wave or heat dome? Yes, there's a difference

It sounds like something out of a horror movie, like “The Blob” or “Godzilla.” But “heat domes” are far from fiction — and the West could be facing one this week.

The term “heat dome” refers to a ridge of high pressure that persists over a large geographical region, delivering high temperatures that linger for days or weeks on end.

An infamous heat dome occurred in 2021, when triple-digit temperatures stifled the Pacific Northwest for 27 days, contributing to hundreds of deaths and spawning multiple research studies.

Experts say it’s not the same as a heat wave, which is conventionally defined as a spell of three or more abnormally hot days. But the term has gained prominence in recent years as climate change, El Niño and other variables have warmed global temperatures, shifted weather patterns and contributed to worsening hazards.

The term “does seem to have caught on in the past decade or less,” said John Abatzoglou, a professor of climatology at UC Merced, who co-authored a recent study about the 2021 heat dome.

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He said one authority on the issue is the American Meteorological Society, which maintains a glossary of such terms. That group added “heat dome” to its index in March 2022, defining it as “an exceptionally hot air mass that develops when high pressure aloft prevents warm air below from rising, thus trapping the warm air as if it were in a dome.”

Abatzoglou expanded on the definition even further, noting that heat domes aren’t just large and persistent, but typically set up over land and in warm seasons.

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“We can have heat waves without heat domes,” he said, particularly in coastal Southern California, where offshore winds can bring hot temperatures south and west of the mountains while other parts of California stay cooler.

“Generally heat domes instead affect very large geographic areas — synchronizing hot and sometimes very dry conditions — which can lead to additional challenges that may not materialize with ‘local’ heat wave events,” he said.

Not everyone agrees, however. The National Weather Service has no official definition for “heat dome” in its glossary, and meteorologists there are less likely to use the term.

“I’ve heard in the media the term ‘heat dome,’ but we really don’t use that,” said Dan Harty, a meteorologist with the National Weather Service in Hanford. “Heat wave is typically what we refer to.”

Harty said the NWS typically defines a heat wave as at least two consecutive days of high heat risk. He said the incoming event is expected to peak in the Central Valley on Thursday with temperatures as hot as 108 degrees in Fresno and 107 degrees in Madera, both of which could set daily records.

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The agency has issued an excessive heat warning that stretches from portions of Los Angeles almost to the Oregon border through Friday, advising residents of dangerously hot conditions and increased potential for heat-related illnesses.

Sara Purdue, a meteorologist with the NWS in Sacramento, said either term could be used for the incoming event, but “it’s not a particularly impressive heat dome.” The heat is expected to dissipate in the region slightly by the weekend, but could be followed by more heat next week.

“Usually when people refer to a heat dome, it’s stationary for whatever reason, so it’s not moving quickly out of the area,” she said. “It’s being blocked by other other areas of pressure, east and west.”

Even less certain is whether the blocking, or ridging, pattern associated with heat domes are becoming more frequent. Some scientific literature points to this being the case, including a 2012 study that found slower patterns favoring extreme weather are becoming more common in mid-latitude regions.

A more recent study on the 2021 heat dome shows that climate change “is actually favoring the jet stream behavior that produces these stagnant high pressure systems and the extreme heat and drought associated with them,” said Michael Mann, one of the study’s authors and a presidential distinguished professor at the University of Pennsylvania, in an email. (The jet stream is the river of air that moves weather systems eastward across the globe).

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Mann noted that heat domes aren’t just warm at the surface like heat waves, but have a deep layer of warm air and high pressure associated with sinking dry hot air. He said they’re the sort of air masses often associated with desert conditions — and with a particular jet stream pattern called an “omega block” because of its shape.

“Our work shows that climate models aren’t doing a good job yet in capturing this effect, meaning that the models are probably underestimating the impact that climate change is having on these persistent summer weather extremes (heat domes, heat waves, wildfires, as well as extreme flooding events),” he said.

And while the term “heat dome” has recently risen in prominence, Mann said it goes back nearly half a century. However, climate change is leading to increased incidents of the underlying conditions associated with such events, he said.

In fact, research has shown heat waves now occur three times as often as they did in the 1960s. Heat domes, like the one that smothered the Pacific Northwest in 2021, are also 150 times more likely due to climate change, another study found.

Climate change is also leading to warmer global temperatures and greater temperature extremes, Abatzoglou said, “so when events like this do occur, the temperatures along with them are substantially warmer.”

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In some ways, then, the term heat dome is not unlike other meteorological phenomena that have gained prominence in recent years, including real terms such as atmospheric rivers and bomb cyclones, and more colorful terms such as firenadoes and hurriquakes.

Another recent coinage is the “ridiculously resilient ridge,” a phrase from UCLA climate scientist Daniel Swain used to describe a blocking pattern to the west of California in the winter months that deflects storms north of the region.

Abatzoglou said heat domes are somewhat similar, except that the ridge sets up over land with the jet stream often well to the north, and the ridge pattern gets “stuck.”

But extreme heat is particularly dangerous — among the deadliest of all extreme weather events — and often, the first heat wave of the year is the most impactful because people have not yet acclimated, Abatzoglou said. Sometimes, the most important task is accurately communicating that threat to the public.

“I’ve said these are ‘ridging events,’ and to many people that’s jargon and it doesn’t translate,” he said. “And so we have to go from talking about ‘500 millibar geopotential heights’ that a really small audience appreciates and understands, to something that captures the essence of the event. And this really is a large blocking.”

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Cluster of farmworkers diagnosed with rare animal-borne disease in Ventura County

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Cluster of farmworkers diagnosed with rare animal-borne disease in Ventura County

A cluster of workers at Ventura County berry farms have been diagnosed with a rare disease often transmitted through sick animals’ urine, according to a public health advisory distributed to local doctors by county health officials Tuesday.

The bacterial infection, leptospirosis, has resulted in severe symptoms for some workers, including meningitis, an inflammation of the brain lining and spinal cord. Symptoms for mild cases included headaches and fevers.

The disease, which can be fatal, rarely spreads from human to human, according to the U.S. Centers for Disease Control and Prevention.

Ventura County Public Health has not given an official case count but said it had not identified any cases outside of the agriculture sector. The county’s agriculture commissioner was aware of 18 cases, the Ventura County Star reported.

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The health department said it was first contacted by a local physician in October, who reported an unusual trend in symptoms among hospital patients.

After launching an investigation, the department identified leptospirosis as a probable cause of the illness and found most patients worked on caneberry farms that utilize hoop houses — greenhouse structures to shelter the crops.

As the investigation to identify any additional cases and the exact sources of exposure continues, Ventura County Public Health has asked healthcare providers to consider a leptospirosis diagnosis for sick agricultural workers, particularly berry harvesters.

Rodents are a common source and transmitter of disease, though other mammals — including livestock, cats and dogs — can transmit it as well.

The disease is spread through bodily fluids, such as urine, and is often contracted through cuts and abrasions that contact contaminated water and soil, where the bacteria can survive for months.

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Humans can also contract the illness through contaminated food; however, the county health agency has found no known health risks to the general public, including through the contact or consumption of caneberries such as raspberries and blackberries.

Symptom onset typically occurs between two and 30 days after exposure, and symptoms can last for months if untreated, according to the CDC.

The illness often begins with mild symptoms, with fevers, chills, vomiting and headaches. Some cases can then enter a second, more severe phase that can result in kidney or liver failure.

Ventura County Public Health recommends agriculture and berry harvesters regularly rinse any cuts with soap and water and cover them with bandages. They also recommend wearing waterproof clothing and protection while working outdoors, including gloves and long-sleeve shirts and pants.

While there is no evidence of spread to the larger community, according to the department, residents should wash hands frequently and work to control rodents around their property if possible.

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Pet owners can consult a veterinarian about leptospirosis vaccinations and should keep pets away from ponds, lakes and other natural bodies of water.

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Political stress: Can you stay engaged without sacrificing your mental health?

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Political stress: Can you stay engaged without sacrificing your mental health?

It’s been two weeks since Donald Trump won the presidential election, but Stacey Lamirand’s brain hasn’t stopped churning.

“I still think about the election all the time,” said the 60-year-old Bay Area resident, who wanted a Kamala Harris victory so badly that she flew to Pennsylvania and knocked on voters’ doors in the final days of the campaign. “I honestly don’t know what to do about that.”

Neither do the psychologists and political scientists who have been tracking the country’s slide toward toxic levels of partisanship.

Fully 69% of U.S. adults found the presidential election a significant source of stress in their lives, the American Psychological Assn. said in its latest Stress in America report.

The distress was present across the political spectrum, with 80% of Republicans, 79% of Democrats and 73% of independents surveyed saying they were stressed about the country’s future.

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That’s unhealthy for the body politic — and for voters themselves. Stress can cause muscle tension, headaches, sleep problems and loss of appetite. Chronic stress can inflict more serious damage to the immune system and make people more vulnerable to heart attacks, strokes, diabetes, infertility, clinical anxiety, depression and other ailments.

In most circumstances, the sound medical advice is to disengage from the source of stress, therapists said. But when stress is coming from politics, that prescription pits the health of the individual against the health of the nation.

“I’m worried about people totally withdrawing from politics because it’s unpleasant,” said Aaron Weinschenk, a political scientist at the University of Wisconsin–Green Bay who studies political behavior and elections. “We don’t want them to do that. But we also don’t want them to feel sick.”

Modern life is full of stressors of all kinds: paying bills, pleasing difficult bosses, getting along with frenemies, caring for children or aging parents (or both).

The stress that stems from politics isn’t fundamentally different from other kinds of stress. What’s unique about it is the way it encompasses and enhances other sources of stress, said Brett Ford, a social psychologist at the University of Toronto who studies the link between emotions and political engagement.

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For instance, she said, elections have the potential to make everyday stressors like money and health concerns more difficult to manage as candidates debate policies that could raise the price of gas or cut off access to certain kinds of medical care.

Layered on top of that is the fact that political disagreements have morphed into moral conflicts that are perceived as pitting good against evil.

“When someone comes into power who is not on the same page as you morally, that can hit very deeply,” Ford said.

Partisanship and polarization have raised the stakes as well. Voters who feel a strong connection to a political party become more invested in its success. That can make a loss at the ballot box feel like a personal defeat, she said.

There’s also the fact that we have limited control over the outcome of an election. A patient with heart disease can improve their prognosis by taking medicine, changing their diet, getting more exercise or quitting smoking. But a person with political stress is largely at the mercy of others.

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“Politics is many forms of stress all rolled into one,” Ford said.

Weinschenk observed this firsthand the day after the election.

“I could feel it when I went into my classroom,” said the professor, whose research has found that people with political anxiety aren’t necessarily anxious in general. “I have a student who’s transgender and a couple of students who are gay. Their emotional state was so closed down.”

That’s almost to be expected in a place like Wisconsin, whose swing-state status caused residents to be bombarded with political messages. The more campaign ads a person is exposed to, the greater the risk of being diagnosed with anxiety, depression or another psychological ailment, according to a 2022 study in the journal PLOS One.

Political messages seem designed to keep voters “emotionally on edge,” said Vaile Wright, a licensed psychologist in Villa Park, Ill., and a member of the APA’s Stress in America team.

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“It encourages emotion to drive our decision-making behavior, as opposed to logic,” Wright said. “When we’re really emotionally stimulated, it makes it so much more challenging to have civil conversation. For politicians, I think that’s powerful, because emotions can be very easily manipulated.”

Making voters feel anxious is a tried-and-true way to grab their attention, said Christopher Ojeda, a political scientist at UC Merced who studies mental health and politics.

“Feelings of anxiety can be mobilizing, definitely,” he said. “That’s why politicians make fear appeals — they want people to get engaged.”

On the other hand, “feelings of depression are demobilizing and take you out of the political system,” said Ojeda, author of “The Sad Citizen: How Politics is Depressing and Why it Matters.”

“What [these feelings] can tell you is, ‘Things aren’t going the way I want them to. Maybe I need to step back,’” he said.

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Genessa Krasnow has been seeing a lot of that since the election.

The Seattle entrepreneur, who also campaigned for Harris, said it grates on her to see people laughing in restaurants “as if nothing had happened.” At a recent book club meeting, her fellow group members were willing to let her vent about politics for five minutes, but they weren’t interested in discussing ways they could counteract the incoming president.

“They’re in a state of disengagement,” said Krasnow, who is 56. She, meanwhile, is looking for new ways to reach young voters.

“I am exhausted. I am so sad,” she said. “But I don’t believe that disengaging is the answer.”

That’s the fundamental trade-off, Ojeda said, and there’s no one-size-fits-all solution.

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“Everyone has to make a decision about how much engagement they can tolerate without undermining their psychological well-being,” he said.

Lamirand took steps to protect her mental health by cutting social media ties with people whose values aren’t aligned with hers. But she will remain politically active and expects to volunteer for phone-banking duty soon.

“Doing something is the only thing that allows me to feel better,” Lamirand said. “It allows me to feel some level of control.”

Ideally, Ford said, people would not have to choose between being politically active and preserving their mental health. She is investigating ways to help people feel hopeful, inspired and compassionate about political challenges, since these emotions can motivate action without triggering stress and anxiety.

“We want to counteract this pattern where the more involved you are, the worse you are,” Ford said.

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The benefits would be felt across the political spectrum. In the APA survey, similar shares of Democrats, Republicans and independents agreed with statements like, “It causes me stress that politicians aren’t talking about the things that are most important to me,” and, “The political climate has caused strain between my family members and me.”

“Both sides are very invested in this country, and that is a good thing,” Wright said. “Antipathy and hopelessness really doesn’t serve us in the long run.”

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Video: SpaceX Unable to Recover Booster Stage During Sixth Test Flight

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Video: SpaceX Unable to Recover Booster Stage During Sixth Test Flight

President-elect Donald Trump joined Elon Musk in Texas and watched the launch from a nearby location on Tuesday. While the Starship’s giant booster stage was unable to repeat a “chopsticks” landing, the vehicle’s upper stage successfully splashed down in the Indian Ocean.

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