[ad_1]
Bands of fast-moving wind that blow west to east around the globe play a crucial role in weather – a poleward shift in parts of these jet streams could cause dramatic changes in weather from the western US to the Mediterranean
[ad_2]
Source link
Tag: extreme weather
-
The jet stream may be starting to shift in response to climate change
-
A Rare Coincidence of La Niña Events Will Weaken Hurricane Season
[ad_1]
While much weaker than their Pacific counterpart, Atlantic Niñas can, however, partially counteract La Niñas by weakening summer winds that help drive the upwelling that cools the eastern Pacific.
Why Are Both Happening Now?
In July and August 2024, meteorologists noted cooling that appeared to be the development of an Atlantic Niña along the equator. The winds at the ocean surface had been weak through most of the summer, and sea surface temperatures there were quite warm until early June, so signs of an Atlantic Niña emerging were a surprise.
At the same time, waters along the equator in the eastern Pacific were also cooling, with La Niña conditions expected there by October or November.
Getting a Pacific-Atlantic Niña combination is rare but not impossible. It’s like finding two different pendulums that are weakly coupled to swing in opposite directions moving together in time. The combinations of La Niña and Atlantic Niño, or El Niño and Atlantic Niña are more common.
Good News or Bad for Hurricane Season?
An Atlantic Niña may initially suggest good news for those living in hurricane-prone areas.
Cooler than average waters off the coast of Africa can suppress the formation of African easterly waves. These are clusters of thunderstorm activity that can form into tropical disturbances and eventually tropical storms or hurricanes.
Tropical storms draw energy from the process of evaporating water associated with warm sea surface temperatures. So, cooling in the tropical Atlantic could weaken this process. That would leave less energy for the thunderstorms, which would reduce the probability of a tropical cyclone forming.
However, the NOAA takes all factors into account when it updates its Atlantic hurricane season outlook, released in early August, and it still anticipates an extremely active 2024 season. Tropical storm season typically peaks in early to mid-September.
Two reasons are behind the busy forecast: The near record-breaking warm sea surface temperatures in much of the North Atlantic can strengthen hurricanes. And the expected development of a La Niña in the Pacific tends to weaken wind shear—the change in wind speed with height that can tear apart hurricanes. La Niña’s much stronger effects can override any impacts associated with the Atlantic Niña.
Exacerbating the Problem: Global Warming
The past two years have seen exceptionally high ocean temperatures in the Atlantic and around much of the world’s oceans. The two Niñas are likely to contribute some cooling relief for certain regions, but it may not last long.
In addition to these cycles, the global warming trend caused by rising greenhouse gas emissions is raising the baseline temperatures and can fuel major hurricanes.
[ad_2]
Source link -
Your Guide to Surviving Extreme Weather
[ad_1]
This story originally appeared on Grist and is part of the Climate Desk collaboration.
No matter where you live, extreme weather can hit your area, causing damage to homes, power outages, and dangerous or deadly conditions. If you’re on the coast, it may be a hurricane; in the Midwest or South, a tornado; in the West, wildfires; and as we’ve seen in recent years, anywhere can experience heat waves or flash flooding.
Living through a disaster and its aftermath can be both traumatic and chaotic, from the immediate losses of life and belongings to conflicting information around where to access aid. The weeks and months after may be even more difficult, as the attention on your community is gone but civic services and events have stalled or changed drastically.
Grist compiled this resource guide to help you stay prepared and informed. It looks at everything from how to find the most accurate forecasts to signing up for emergency alerts to the roles that different agencies play in disaster aid.
Where to Find the Facts on Disasters
These days, many people find out about disasters in their area via social media. But it’s important to make sure the information you’re receiving is accurate. Here’s where to find the facts on extreme weather and the most reliable places to check for emergency alerts and updates.
Your local emergency manager: Your city or county will have an emergency management department, which is part of the local government. In larger cities, it’s often a separate agency; in smaller communities, fire chiefs or sheriff’s offices may manage emergency response and alerts. Emergency managers are responsible for communicating with the public about disasters, managing rescue and response efforts, and coordinating between different agencies. They usually have an SMS-based emergency alert system, so sign up for those via your local website. (Note: Some cities have multiple languages available, but most emergency alerts are only in English.) Many emergency management agencies are active on Facebook, so check there for updates as well.
Local news: The local television news and social media accounts from verified news sources will have live updates during and after a storm. Follow your local newspaper and television station on Facebook or other social media, or check their websites regularly.
[ad_2]
Source link -
Bayesian Yacht Sinking: Climate Change Created Perfect Storm for
[ad_1]
The waterspout blamed for the deadly sinking of a luxury superyacht carrying the British tech billionaire Mike Lynch in Italy has been called a freak “black swan” event. But scientists believe this kind of marine tornado is becoming more common with global warming.
While the cause of the sinking of the Bayesian hasn’t officially been determined, weather conditions and witness reports from Sicily, where the yacht was anchored off the coast, have led experts to suspect a waterspout, a whirling column of air and water mist. The key factor for waterspout formation is warm water—and the past year has seen the ocean surface heat up to record-breaking temperatures, in part due to climate change.
“If this rate of warming is going to be continuing in the future, it’s very possible these phenomena will be common and not rare,” says Michalis Sioutas, a meteorology PhD who studies waterspouts in Greece and is a board member of the Hellenic Meteorological Society. “It’s very possible to talk about waterspouts or even tornadoes and extreme storms becoming common.”
The 180-foot Bayesian sank in a matter of minutes after a sudden storm with strong winds and intense lightning snapped its mast around 4 am on Monday. Fifteen people who had been aboard were rescued, and one person was found dead. Six people are missing, including British tech billionaire Mike Lynch, who was recently cleared of fraud charges over the sale of his company to Hewlett-Packard. On Wednesday, the bodies of five people were recovered from the sunken ship but have yet to be identified.
Fishermen saw a waterspout near the yacht shortly before it sank, and a nearby schooner was tossed about by what its captain, Karsten Borner, called a “hurricane gust,” which he believes capsized the Bayesian. Experts have said the conditions were ripe for a waterspout.
This extreme weather phenomenon occurs when warm, moist air rises rapidly over water, spinning as winds change direction at different heights. The result is a long, bending funnel of spray between the water and the clouds, tapering off as it rises as much as 10,000 feet into the heavens.
It comes in two flavors. The more vanilla kind is a fair weather waterspout, which forms in relatively calm and even sunny conditions, often under a billowy cumulus cloud. It happens more often in places like the Great Lakes and the Florida Keys, reaches wind speeds of 50 miles per hour, and usually breaks up before it can cause significant damage.
Then there are severe waterspouts, essentially tornadoes over water, which “are another beast” entirely, according to Wade Szilagyi, a retired forecaster at the Meteorological Service of Canada who now directs the International Center for Waterspout Research. These tornadic waterspouts can move from land to water, or vice versa, and twist at 125 miles per hour or more. They’ve been known to throw debris, rip apart buildings, and overturn boats.
[ad_2]
Source link -
The Run of Record-Breaking Heat Has Ended, for Now
[ad_1]
But global warming doesn’t happen in a smooth progression. Like housing prices, the general trend is up, but there are ups and downs along the way.
Behind much of the ups and downs is the El Niño phenomenon. An El Niño event is a reorganization of the water across the vast reaches of the Pacific Ocean. El Niño is so important to the workings of worldwide weather, as it increases the temperature of the air on average across all of Earth’s surface, not only over the Pacific. Between El Niño events, conditions may be neutral or in an opposite state called La Niña that tends to cool global temperatures. The oscillation between these extremes is irregular, and El Niño conditions tend to recur after three to seven years.
The warm El Niño phase of this cycle began to kick in a year ago, reached its peak around the end of 2023, and is now trending neutral, which is why the record-breaking streak has ended.
The 2023–2024 El Niño was strong, but it wasn’t super-strong. It doesn’t fully explain the remarkable degree to which the past year broke temperature records. The exact influence of other factors has yet to be fully untangled.
We know there is a small positive contribution from the sun, which is in a phase of its 11-year sunspot cycle in which it radiates fractionally more energy to the Earth.
Methane (also a byproduct of the fossil fuel industry, alongside cattle and wetlands) is another important greenhouse gas, and its concentration in the air has risen more rapidly in the past decade than over the previous decade.
Scientists are also assessing how much measures to clean up air pollution might be adding to warming, since certain particulate air pollutants can reflect sunlight and influence the formation of clouds.
A Temperature Ratchet
Across the global ocean, 2023 was a devastating summer for coral reefs and surrounding ecosystems in the Caribbean and beyond. This was followed by heavy bleaching across the Great Barrier Reef off Australia during the southern hemisphere summer. While it is El Niño years that tend to see mass mortality events on reefs around the world, it is the underlying climate change trend that is the long-term threat, as corals are struggling to adapt to rising temperature extremes.
[ad_2]
Source link -
To Study Tornados, Bring an Apocalypse-Proof Truck. And Rocket Launchers
[ad_1]
Reed Timmer has been chasing storms for more than two decades, since he intercepted his first tornado in northern Oklahoma as an undergrad majoring in meteorology. During that time, Timmer, who typically logs more than 50,000 miles on the road each year, has intercepted countless tornadoes, each one helping to further his extreme-weather knowledge. “We still don’t completely know what happens inside a tornado,” says Edgar ONeal, a weather journalist who is Timmer’s chase partner.
Enter the Dominator. This is the third iteration of Timmer’s custom-built tornado mobile, which he initially rolled out in the late 2000s. The current Dominator has the chassis of an F350 and weighs 10,000 pounds, enabling it to withstand the debris, gorilla hail, and 150-mph winds that accompany the most powerful of storms. According to Timmer, his “holy grail” is to drive the Dominator to within a quarter-mile of a twister, then shoot a rocket loaded with sensors directly into the heart of the tornado. Timmer has accomplished this once: In May 2019, the rocket tracked the vortex’s pressure drop and frigid air temperature. His team’s hope in the coming year is to launch dozens of rockets at the same time into the swirling updraft of a twister’s “inflow notch.” But even if all those rockets fail, the Dominator is full of its own sensors to capture valuable scientific data. “That’s the whole point,” says ONeal. “You can launch probes into a tornado, or you can be the probe, and that’s the Dominator.”
[ad_2]
Source link -
Mobile weather labs map toll of extreme heat in scorching US cities
[ad_1]
Researchers have been using weather balloons and other technology to map heat in Arizona
Meghan Finnerty/Arizona State University
For the past month, two trucks outfitted with weather sensors, lasers and balloons have roamed Arizona’s scorching cities measuring the heat in extraordinary detail. Such a ground-level view of urban “microclimates” could help cities keep people cool more effectively as climate change boosts temperatures.
“Arizona has been the most extreme environment where we’ve deployed so far because of the intensity of the heat,” says Katia Lamer at Brookhaven National Laboratory in New York, who is leading the survey. On…
[ad_2]
Source link -
Self-cooling artificial grass could help cities handle extreme weather
[ad_1]
Self-cooling artificial turf was tested against ordinary fake grass at a test site in Amsterdam
Joris Voeten
An artificial sports pitch that absorbs rainwater and lets it evaporate on hot days stays much cooler than ordinary fake grass. The self-cooling turf could protect athletes from burns and heat exhaustion while helping cities manage storm waters.
Such surfaces are already being used in Amsterdam, London and Kobe in Japan, says Marjolein van Huijgevoort at KWR Water Research Institute in Nieuwegein, the Netherlands.
“If you have a normal grass field, it stays cool because of the grass itself, because the water in the plants evaporates,” she says. “So this system kind of mimics that natural situation by having water moving up and evaporating.”
Many cities and sports facilities install artificial turf playing fields because excessive use destroys natural grass turfs, says van Huijgevoort. Even in temperate climates like northern Europe, solar heat can warm the plastic turf surfaces to around 70°C (158°F), which endangers athletes’ health and warms urban air – a situation that will only get worse with global warming, she says.
Inspired by “blue-green roofs” that use stored rainwater for a cooling effect, van Huijgevoort and her colleagues created toy-sized models of sports fields in their climate-controlled laboratory. Under the surface, they placed water storage units topped with a 2-centimetre-thick shock pad that was embedded with narrow irrigation cylinders.
Filled with mineral wool fibres, which act like a sponge, these “capillaries” slowly draw water back up to a thin sand layer at the bed of the synthetic grass surface. In heated laboratory conditions, the irrigated water evaporated from the sand, creating a cooling effect on the surface.
Encouraged by those results, the team made 25-square-metre test fields in Amsterdam, including an irrigated natural grass field. During a heatwave when the maximum air temperature measured was 29.8°C (86°F), the conventional artificial turf reached 62.5°C (145°F). The researchers’ self-cooling turf, however, never got hotter than 37°C (99°F) – just 1.7°C warmer than the natural grass field. Even the air above the water-cooled turf was cooler, meaning less heating of the city in general, says van Huijgevoort.
The system is based on a design in which the rate of water rising and the evaporative cooling process depends on various natural factors such as weather conditions. “So water only evaporates when there is demand for cooling,” says van Huijgevoort.
The reservoirs under the turf can hold about 512,000 litres of rainwater under a standard football pitch measuring 100 metres by 64 metres, she says. The capillaries in the shock pad could hold an additional 96,000 litres. That means the fields should help soak up large volumes of water during storms, says van Huijgevoort.
Topics:
[ad_2]
Source link -
How to Exercise Safely During a Heat Wave
[ad_1]
THIS ARTICLE IS republished from The Conversation under a Creative Commons license.
When summer starts with a stifling heat wave, as many places are seeing in 2024, it can pose risks for just about anyone who spends time outside, whether they’re runners, people who walk or cycle to work, outdoor workers, or kids playing sports.
Susan Yeargin, an expert on heat-related illnesses, explains what everyone should think about before spending time outside in a heat wave and how to keep yourself and vulnerable family members and friends safe.
What Are the Risks When Exercising Outside?
The time of day matters if you’re going for a run, or if you’re walking or cycling to work during a heat wave. Early risers or evening runners face less of a risk—the sun isn’t as hot and the air temperature is lower.
But if your normal routine is to go for a run midmorning or over lunch, you probably want to rethink exercising in the heat.
Pretty much everywhere in the US, the hottest part of the day is between 10 am and 6 pm. The body will gain heat from both the air temperature and solar radiation. The ground also heats up, so you’ll feel more heat rising up from the asphalt or grass.
Add humidity to the mix and that will also affect your body’s ability to dissipate heat through sweat.
Don’t forget that the body also generates internal heat when you’re active, whether you’re running or even mowing your lawn. When it’s warm to hot outside, you’re further increasing your heat gain through that exertion. The harder someone runs or cycles, the more heat they’re generating.
Outdoor workers on farms, construction sites, or even walking dogs are often in the heat longer, with less flexibility for breaks.
Do Our Bodies Eventually Adapt to Summer Heat?
It takes about two weeks for the typical person to fully acclimatize to higher temperatures. Over that time, your body makes amazing adaptations to handle the heat.
Your sweat rate improves, dissipating heat more effectively. Your plasma volume expands so you have more blood pumping through your body, so the heart doesn’t have to work as hard. Because your cardiovascular system is more efficient, your body doesn’t heat up as much. You also retain salt a bit better, which helps you keep water in your body.
[ad_2]
Source link -
Tropical storms like Alberto can lead to years of declining incomes
[ad_1]
Houses in Texas surrounded by floodwater from Tropical Storm Alberto in June 2024
Brandon Bell/Getty
Parts of Texas and Mexico were hit by flooding this week driven by Tropical Storm Alberto, the first named storm of what is forecast to be an extremely active Atlantic hurricane season. While overall damages weren’t especially severe, the long-term economic consequences from the storm and others like it could prove to be much more significant.
“We’re learning more and more every year about the ways in which the scars of natural disasters and extreme climate events can be really persistent,” says Christopher…
[ad_2]
Source link