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Unpredictable winds make wildfires an erratic adversary: experts

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Hot weather and dry conditions are the usual suspects in any wildfire season, but a complex interplay of topography and unpredictable winds can create particularly challenging adversaries for firefighters, experts say.

In British Columbia, shifting wind patterns have been a key concern for crews battling a fire in the south Okanagan that has forced the evacuation of hundreds of homes.

Mary-Ann Jenkins, professor emeritus of atmospheric science at York University in Toronto, said fire generally moves in the same direction the wind is blowing.

But mountains can complicate matters, she said.

The Rockies, for instance, influence a range of factors, including humidity and localized wind directions.

“Because of the Rockies, wind can be channelled through valleys. It changes — the wind over ridges in the mountains and also sometimes you have very severe downslope winds,” she said.

“And another thing that people don’t know is that winds going up a hill tend to accelerate. As they go uphill, they get stronger and stronger before they reach the top.”

Jenkins said the Rockies create a unique phenomenon called Chinook winds, which are extremely drying, can be experienced all year around and can add to firefighting woes.

“The weather conditions at the local level in a mountainous region are difficult to forecast. Because there are so many things that can happen due to topography.”

Such unpredictability has been felt acutely around Keremeos, in British Columbia’s south Okanagan. The area’s Indigenous name is “valley of the three winds,” said Tim Roberts, the elected regional director.

On Monday, BC Wildfire Service information officer Bryan Zandberg said winds around the Keremeos Creek fire were light, at about 15 kilometres per hour, which allowed firefighters to make good progress building containment lines.

But the winds still had the potential to push flames south toward the villages of Keremeos and Olalla, as happened last week, he said.

“We’re making really good gains,” he said, but added “if the wind picks up, you know, the wind could take it where it wants to.”

More than 500 homes in the area have been ordered evacuated since the wildfire was reported on July 29.

It’s not just the western side of the country where unpredictable winds can be a factor. In Newfoundland, where a state of emergency was called over the weekend in response to a major fire, changing wind patterns have been making the situation difficult to handle.

The blaze that began in an area called Paradise Lake was within 25 kilometres of the town of Grand Falls-Windsor, and crews were working Monday afternoon to build a fire break to keep the flames from creeping closer to the town, said Jeff Motty, the province’s forest fire duty officer.

In the Northwest Territories, meanwhile, authorities are guarding against a flare-up of a fire on the west side of Marian Lake that had previously been dormant underground.

The Department of Environment and Natural Resources said heavy winds from the south were expected to cause extreme fire behaviour and significant growth of the so-called “zombie fire,” which has grown to about 65 square kilometres.

Prof. Mike Flannigan from Thompson Rivers University said the ingredients for a wildfire include fuel such as grasses and other vegetation, hot and dry weather and winds.

Sometimes it doesn’t even have to be hot, but it has to be dry and windy to fan a fire, said the British Columbia Research Chair in predictive services, emergency management and fire science.

“Once you have a fire started, wind is also really important in how that spreads,” he said in an interview. “It spreads in the direction that the wind is going. So a west wind means the fire is moving from west to east, and it’s most intense in the direction of the wind. It’s like being pushed along by that wind.”

Usually when temperatures drop at night, humidity goes down and winds calm too, he said.

But lately, he said researchers have found nights are staying warm, winds aren’t “possibly” calming as much as they used to, making it challenging for firefighters.

Jenkins said fires also tend to make their own winds because they can create a large convective storm.

A fire can produce a vortex of swirling air along a fire line, she said. Pressure is sucked out of these whirls, which can move erratically, and aren’t easy to observe or predict, she said.

“Sometimes they’re fairly benign, but sometimes they’re not,” Jenkins said. “It spreads fire in a very erratic way and it can take out houses that you didn’t expect, or overwhelm firefighters.”

Flannigan said that fires create hot air that rises, and a void that is filled with a stream of cold air.

“The more quickly it does that, the stronger the winds are,” he said. “Wind is just the movement of air. Fires create their own wind field and the bigger the fire, the more intense the fire, the stronger the wind.”

Even at the scale of a small bonfire, Jenkins said fires create their own winds.

“So, larger fires do very, very interesting things with a degree of magnitude and are fairly more dangerous. That’s a natural aspect of combustion, fuel burning, a wildfire burning.”

This report by The Canadian Press was first published Aug. 8, 2022.

 

Hina Alam, The Canadian Press

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STD epidemic slows as new syphilis and gonorrhea cases fall in US

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NEW YORK (AP) — The U.S. syphilis epidemic slowed dramatically last year, gonorrhea cases fell and chlamydia cases remained below prepandemic levels, according to federal data released Tuesday.

The numbers represented some good news about sexually transmitted diseases, which experienced some alarming increases in past years due to declining condom use, inadequate sex education, and reduced testing and treatment when the COVID-19 pandemic hit.

Last year, cases of the most infectious stages of syphilis fell 10% from the year before — the first substantial decline in more than two decades. Gonorrhea cases dropped 7%, marking a second straight year of decline and bringing the number below what it was in 2019.

“I’m encouraged, and it’s been a long time since I felt that way” about the nation’s epidemic of sexually transmitted infections, said the CDC’s Dr. Jonathan Mermin. “Something is working.”

More than 2.4 million cases of syphilis, gonorrhea and chlamydia were diagnosed and reported last year — 1.6 million cases of chlamydia, 600,000 of gonorrhea, and more than 209,000 of syphilis.

Syphilis is a particular concern. For centuries, it was a common but feared infection that could deform the body and end in death. New cases plummeted in the U.S. starting in the 1940s when infection-fighting antibiotics became widely available, and they trended down for a half century after that. By 2002, however, cases began rising again, with men who have sex with other men being disproportionately affected.

The new report found cases of syphilis in their early, most infectious stages dropped 13% among gay and bisexual men. It was the first such drop since the agency began reporting data for that group in the mid-2000s.

However, there was a 12% increase in the rate of cases of unknown- or later-stage syphilis — a reflection of people infected years ago.

Cases of syphilis in newborns, passed on from infected mothers, also rose. There were nearly 4,000 cases, including 279 stillbirths and infant deaths.

“This means pregnant women are not being tested often enough,” said Dr. Jeffrey Klausner, a professor of medicine at the University of Southern California.

What caused some of the STD trends to improve? Several experts say one contributor is the growing use of an antibiotic as a “morning-after pill.” Studies have shown that taking doxycycline within 72 hours of unprotected sex cuts the risk of developing syphilis, gonorrhea and chlamydia.

In June, the CDC started recommending doxycycline as a morning-after pill, specifically for gay and bisexual men and transgender women who recently had an STD diagnosis. But health departments and organizations in some cities had been giving the pills to people for a couple years.

Some experts believe that the 2022 mpox outbreak — which mainly hit gay and bisexual men — may have had a lingering effect on sexual behavior in 2023, or at least on people’s willingness to get tested when strange sores appeared.

Another factor may have been an increase in the number of health workers testing people for infections, doing contact tracing and connecting people to treatment. Congress gave $1.2 billion to expand the workforce over five years, including $600 million to states, cities and territories that get STD prevention funding from CDC.

Last year had the “most activity with that funding throughout the U.S.,” said David Harvey, executive director of the National Coalition of STD Directors.

However, Congress ended the funds early as a part of last year’s debt ceiling deal, cutting off $400 million. Some people already have lost their jobs, said a spokeswoman for Harvey’s organization.

Still, Harvey said he had reasons for optimism, including the growing use of doxycycline and a push for at-home STD test kits.

Also, there are reasons to think the next presidential administration could get behind STD prevention. In 2019, then-President Donald Trump announced a campaign to “eliminate” the U.S. HIV epidemic by 2030. (Federal health officials later clarified that the actual goal was a huge reduction in new infections — fewer than 3,000 a year.)

There were nearly 32,000 new HIV infections in 2022, the CDC estimates. But a boost in public health funding for HIV could also also help bring down other sexually transmitted infections, experts said.

“When the government puts in resources, puts in money, we see declines in STDs,” Klausner said.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.

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World’s largest active volcano Mauna Loa showed telltale warning signs before erupting in 2022

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WASHINGTON (AP) — Scientists can’t know precisely when a volcano is about to erupt, but they can sometimes pick up telltale signs.

That happened two years ago with the world’s largest active volcano. About two months before Mauna Loa spewed rivers of glowing orange molten lava, geologists detected small earthquakes nearby and other signs, and they warned residents on Hawaii‘s Big Island.

Now a study of the volcano’s lava confirms their timeline for when the molten rock below was on the move.

“Volcanoes are tricky because we don’t get to watch directly what’s happening inside – we have to look for other signs,” said Erik Klemetti Gonzalez, a volcano expert at Denison University, who was not involved in the study.

Upswelling ground and increased earthquake activity near the volcano resulted from magma rising from lower levels of Earth’s crust to fill chambers beneath the volcano, said Kendra Lynn, a research geologist at the Hawaiian Volcano Observatory and co-author of a new study in Nature Communications.

When pressure was high enough, the magma broke through brittle surface rock and became lava – and the eruption began in late November 2022. Later, researchers collected samples of volcanic rock for analysis.

The chemical makeup of certain crystals within the lava indicated that around 70 days before the eruption, large quantities of molten rock had moved from around 1.9 miles (3 kilometers) to 3 miles (5 kilometers) under the summit to a mile (2 kilometers) or less beneath, the study found. This matched the timeline the geologists had observed with other signs.

The last time Mauna Loa erupted was in 1984. Most of the U.S. volcanoes that scientists consider to be active are found in Hawaii, Alaska and the West Coast.

Worldwide, around 585 volcanoes are considered active.

Scientists can’t predict eruptions, but they can make a “forecast,” said Ben Andrews, who heads the global volcano program at the Smithsonian Institution and who was not involved in the study.

Andrews compared volcano forecasts to weather forecasts – informed “probabilities” that an event will occur. And better data about the past behavior of specific volcanos can help researchers finetune forecasts of future activity, experts say.

(asterisk)We can look for similar patterns in the future and expect that there’s a higher probability of conditions for an eruption happening,” said Klemetti Gonzalez.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.

The Canadian Press. All rights reserved.

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Waymo’s robotaxis now open to anyone who wants a driverless ride in Los Angeles

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Waymo on Tuesday opened its robotaxi service to anyone who wants a ride around Los Angeles, marking another milestone in the evolution of self-driving car technology since the company began as a secret project at Google 15 years ago.

The expansion comes eight months after Waymo began offering rides in Los Angeles to a limited group of passengers chosen from a waiting list that had ballooned to more than 300,000 people. Now, anyone with the Waymo One smartphone app will be able to request a ride around an 80-square-mile (129-square-kilometer) territory spanning the second largest U.S. city.

After Waymo received approval from California regulators to charge for rides 15 months ago, the company initially chose to launch its operations in San Francisco before offering a limited service in Los Angeles.

Before deciding to compete against conventional ride-hailing pioneers Uber and Lyft in California, Waymo unleashed its robotaxis in Phoenix in 2020 and has been steadily extending the reach of its service in that Arizona city ever since.

Driverless rides are proving to be more than just a novelty. Waymo says it now transports more than 50,000 weekly passengers in its robotaxis, a volume of business numbers that helped the company recently raise $5.6 billion from its corporate parent Alphabet and a list of other investors that included venture capital firm Andreesen Horowitz and financial management firm T. Rowe Price.

“Our service has matured quickly and our riders are embracing the many benefits of fully autonomous driving,” Waymo co-CEO Tekedra Mawakana said in a blog post.

Despite its inroads, Waymo is still believed to be losing money. Although Alphabet doesn’t disclose Waymo’s financial results, the robotaxi is a major part of an “Other Bets” division that had suffered an operating loss of $3.3 billion through the first nine months of this year, down from a setback of $4.2 billion at the same time last year.

But Waymo has come a long way since Google began working on self-driving cars in 2009 as part of project “Chauffeur.” Since its 2016 spinoff from Google, Waymo has established itself as the clear leader in a robotaxi industry that’s getting more congested.

Electric auto pioneer Tesla is aiming to launch a rival “Cybercab” service by 2026, although its CEO Elon Musk said he hopes the company can get the required regulatory clearances to operate in Texas and California by next year.

Tesla’s projected timeline for competing against Waymo has been met with skepticism because Musk has made unfulfilled promises about the company’s self-driving car technology for nearly a decade.

Meanwhile, Waymo’s robotaxis have driven more than 20 million fully autonomous miles and provided more than 2 million rides to passengers without encountering a serious accident that resulted in its operations being sidelined.

That safety record is a stark contrast to one of its early rivals, Cruise, a robotaxi service owned by General Motors. Cruise’s California license was suspended last year after one of its driverless cars in San Francisco dragged a jaywalking pedestrian who had been struck by a different car driven by a human.

Cruise is now trying to rebound by joining forces with Uber to make some of its services available next year in U.S. cities that still haven’t been announced. But Waymo also has forged a similar alliance with Uber to dispatch its robotaxi in Atlanta and Austin, Texas next year.

Another robotaxi service, Amazon’s Zoox, is hoping to begin offering driverless rides to the general public in Las Vegas at some point next year before also launching in San Francisco.

The Canadian Press. All rights reserved.

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