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Lightning strikes will double in Arctic as climate warms
The uptick in Arctic lightning could cause more wildfires, potentially triggering a feedback loop that releases massive amounts of carbon into the atmosphere.
- In recent years, researchers have recorded unusually high numbers of lightning strikes and wildfires in Arctic regions.
- A new study explored how increased lightning could cause a "lightning-fire-vegetation feedback loop" that could accelerate permafrost loss.
- To better monitor changing conditions in the Arctic, the researchers called for more high-quality lightning monitoring systems.
Lighting strikes in the Arctic may increase by approximately 100 percent by the end of the 21st century, according to a new study published in Nature Climate Change. If that happens, places like Alaska could suffer significantly higher rates of wildfires and permafrost loss, both of which could accelerate warming in the Arctic.
Some evidence suggests these changes are already underway. In 2015, Alaska suffered the second-most wildfires on record, burning more than 5.1 million acres across the state's northern region. Although it's difficult to measure, lightning likely started many of these fires.
Still, lightning is relatively rare in the Arctic. That's because lightning occurs when warm, moist air rises to meet cold air, which builds up electrical charge. When that charge exceeds a certain threshold, lightning strikes. Because places like Alaska have relatively cold, dry air, thunderstorms only form occasionally.
But climate change may be changing that. In 2019, the National Weather Service's office in Fairbanks, Alaska, reported an unusually high number of lightning strikes within 300 miles of the North Pole. The uptick in lighting may be no surprise, considering the Arctic is warming by more than twice the global average.
In the recent study, researchers used satellite observations and climate data to explore how increasingly frequent lightning could transform the Arctic through changes like increased wildfires and permafrost loss.
"We projected how lightning in high-latitude boreal forests and Arctic tundra regions will change across North America and Eurasia," Yang Chen, study author and research scientist in the UCI Department of Earth System Science, said in a press release. "The size of the lightning response surprised us because expected changes at mid-latitudes are much smaller."
What's especially concerning about the uptick in Arctic lightning is that it could start a "lightning-fire-vegetation feedback loop."
The researchers explained how more lightning could cause more wildfires, which would burn away many of the shrubs, mosses, and other low-lying plants covering the Arctic terrain. Without those plants covering the ground, soil temperatures would rise, making it easier for deciduous trees to grow.
That might sound like a good thing. But expanding forests could also cause regional temperatures to rise because they would absorb more sunlight than the reflective, snow-covered Arctic terrain currently does. What's more, wildfires would melt Arctic permafrost, which stores massive amounts of organic carbon.
The end result of the lightning-fire-vegetation feedback loop would be the release of carbon into the atmosphere.
Still, the variability in climate modeling and lightning monitoring makes it difficult to predict future changes with a high degree of accuracy.
"This phenomenon is very sporadic, and it's very difficult to measure accurately over long time periods," James T. Randerson, study co-author and professor in the Department of Earth System Science at the University of California, Irvine, said in the press release. "It's so rare to have lightning above the Arctic Circle."
The researchers concluded the study by calling for more high-quality lightning monitoring systems, based on the ground and in space.
"Given the large amount of permafrost soil carbon stored in northern ecosystems, this analysis highlights the importance of improving lightning monitoring in the Arctic and the need to develop better models of lightning, fire dynamics, and feedback with vegetation and soils," they wrote.
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The idea of 'absolute time' is an illusion. Physics and subjective experience reveal why.
- Since Einstein posited his theory of general relativity, we've understood that gravity has the power to warp space and time.
- This "time dilation" effect occurs even at small levels.
- Outside of physics, we experience distortions in how we perceive time — sometimes to a startling extent.
Physics without time<p>In his book "The Order of Time," Italian theoretical physicist Carlo Rovelli suggests that our perception of time — our sense that time is forever flowing forward — could be a highly subjective projection. After all, when you look at reality on the smallest scale (using equations of quantum gravity, at least), time vanishes.</p><p style="margin-left: 20px;">"If I observe the microscopic state of things," writes Rovelli, "then the difference between past and future vanishes … in the elementary grammar of things, there is no distinction between 'cause' and 'effect.'"</p><p>So, why do we perceive time as flowing <em>forward</em>? Rovelli notes that, although time disappears on extremely small scales, we still obviously perceive events occur sequentially in reality. In other words, we observe entropy: Order changing into disorder; an egg cracking and getting scrambled.</p><p>Rovelli says key aspects of time are described by the second law of thermodynamics, which states that heat always passes from hot to cold. This is a one-way street. For example, an ice cube melts into a hot cup of tea, never the reverse. Rovelli suggests a similar phenomenon might explain why we're only able to perceive the past and not the future.</p><p style="margin-left: 20px;">"Any time the future is definitely distinguishable from the past, there is something like heat involved," Rovelli wrote for the <a href="https://www.ft.com/content/ce6ef7b8-429a-11e8-93cf-67ac3a6482fd" target="_blank"><em>Financial Times</em></a>. "Thermodynamics traces the direction of time to something called the 'low entropy of the past', a still mysterious phenomenon on which discussions rage."</p>
The strange subjectivity of time<p>Time moves differently atop a mountain than it does on a beach. But you don't need to travel any distance at all to experience strange distortions in your perception of time. In moments of life-or-death fear, for example, your brain would release large amounts of adrenaline, which would speed up your internal clock, causing you to perceive the outside world as moving slowly.<br></p><p>Another common distortion occurs when we focus our attention in particular ways.</p><p style="margin-left: 20px;">"If you're thinking about how time is <em>currently</em> passing by, the biggest factor influencing your time perception is attention," Aaron Sackett, associate professor of marketing at the University of St. Thomas, told <em><a href="https://gizmodo.com/why-does-time-slow-down-and-speed-up-1840133782" target="_blank">Gizmodo</a></em>.<em> "</em>The more attention you give to the passage of time, the slower it tends to go. As you become distracted from time's passing—perhaps by something interesting happening nearby, or a good daydreaming session—you're more likely to lose track of time, giving you the feeling that it's slipping by more quickly than before. "Time flies when you're having fun," they say, but really, it's more like "time flies when you're thinking about other things." That's why time will also often fly by when you're definitely <em>not</em> having fun—like when you're having a heated argument or are terrified about an upcoming presentation."</p><p>One of the most mysterious ways people experience time-perception distortions is through psychedelic drugs. In an interview with <a href="https://www.theguardian.com/books/2018/apr/14/carlo-rovelli-exploding-commonsense-notions-order-of-time-interview" target="_blank"><em>The Guardian</em></a>, Rovelli described a time he experimented with LSD.</p><p style="margin-left: 20px;">"It was an extraordinarily strong experience that touched me also intellectually," he said. "Among the strange phenomena was the sense of time stopping. Things were happening in my mind but the clock was not going ahead; the flow of time was not passing any more. It was a total subversion of the structure of reality."<br></p><p>It seems few scientists or philosophers believe time is completely an illusion.</p><p style="margin-left: 20px;">"What we call <em>time</em> is a rich, stratified concept; it has many layers," Rovelli told <em><a href="https://physicstoday.scitation.org/do/10.1063/PT.6.4.20190219a/full/" target="_blank">Physics Today</a>.</em> "Some of time's layers apply only at limited scales within limited domains. This does not make them illusions."</p>What <em>is</em> an illusion is the idea that time flows at an absolute rate. The river of time might be flowing forever forward, but it moves at different speeds, between people, and even within your own mind.
The world's 10 most affected countries are spending up to 59% of their GDP on the effects of violence.
- Conflict and violence cost the world more than $14 trillion a year.
- That's the equivalent of $5 a day for every person on the planet.
- Research shows that peace brings prosperity, lower inflation and more jobs.
- Just a 2% reduction in conflict would free up as much money as the global aid budget.
- Report urges governments to improve peacefulness, especially amid COVID-19.
The lush biodiversity of South America's rainforests is rooted in one of the most cataclysmic events that ever struck Earth.
- One especially mysterious thing about the asteroid impact, which killed the dinosaurs, is how it transformed Earth's tropical rainforests.
- A recent study analyzed ancient fossils collected in modern-day Colombia to determine how tropical rainforests changed after the bolide impact.
- The results highlight how nature is able to recover from cataclysmic events, though it may take millions of years.