Category: Environment

Lightning’s Strange Physics Still Stump Scientists

By Carl Engelking | August 31, 2016 2:37 pm


Every day on this planet, roughly 4 to 8 million bolts of electricity the width of a finger connect heaven to earth, discharging a current of 30,000 amperes and heating the air to 18,000 degrees Fahrenheit.

It’s no wonder ancient cultures believed lightning was the chosen weaponry of pissed-off gods. You’ve probably seen the grizzly aftermath of a recent strike in Norway that killed 323 reindeer. Wired’s Megan Molteni published an excellent run-down on why centuries of Santa’s sleigh-pullers were doomed atop the Nordic permafrost:

“When lightning strikes, the current flows into the ground and outward, following the path of least resistance. In a warmer place, the electricity would penetrate deep into the soil and disperse quickly (this is called grounding). But in a place like the Hardangervidda, as the current runs into the soil and hits the permafrost layer, it instead spreads out along the surface of the soil, which is saturated with water from annual cycles of melting—and in this case, the massive rainstorms that generated the lightning strike. So the area that gets zapped is way bigger.”

Although lightning has long captured our attention, it wasn’t until the 18th century that scientists started peeling back mythology to understand this frightful electrostatic display. In 1752, French scientists Thomas-Francois Dalibard and Georges-Louis Leclerc, successfully tangoed with lightning when a bolt struck a 40-foot metal pole that they had anchored in a wine bottle, confirming a hypothesis formulated by Benjamin Franklin.

But more than 250 years after Dalibard and Leclerc’s experiment, scientists are still trying to answer fundamental questions about lightning. At the Florida Institute of Technology, Hamid Rassoul, a veteran space scientist and physics professor, founded the school’s Lightning Research Group to carry on the shocking investigations that started centuries ago.

The following are a few of the nagging questions they are trying to answer.

How Does Lightning Begin?

Who hasn’t been shocked while reaching for a doorknob?

The zap you feel is the result of passing the excess electrons clinging to your finger onto the positively charged doorknob. As your finger nears the knob, the voltage is so high that it causes the air to break down and act like a conductor.

The dielectric breakdown of air is very predictable, it always occurs in an electric field that reaches 3 million volts per meter. It’s a fundamental quantity that’s been established in the lab, and tested over, and over, and over again.

The same should hold true for lightning, which is static electricity on a grand scale. But, for some reason, air breaks down inside a cloud when the electric field reaches just 2 million volts per meter, far weaker than expected.

“That defies the laws of physics, or at least everything we know at this point,” says Rassoul. “Nature is managing to create a spark within an environment that doesn’t meet the same expectations in the lab.”

Rassoul says ice particles in the cloud may interact in a way that initiates the spark sooner than expected, but it’s still unclear what gives lightning its final push. Understanding lightning initiation remains the so-called “Holy Grail” of lightning research.

“It’s one of the biggest mysteries of lightning, and for the past 10 years we have been trying to answer that one,” he says.

How Does Lightning Travel?

Bolts from the blue originate in anvil clouds, but can travel vast distances. A single bolt, for example, can travel from a storm on one side of a mountain range and strike on the other side. Even after covering vast distances, they still pack a 130,000-amp punch four times higher than typical strikes — that’s what gives scientists fits.


A lightning flash captured by a high-speed camera. (Credit: Geospace Physics Laboratory, Department of Physics and Space Sciences, Florida Institute of Technology)

If you built a gun that could fire packets, or bullets, of electrons, you’d run into a problem with range. Say you set an apple on your friend’s head, and you wanted to peg it with an electron bullet from a distance 300 feet. By the time your bullet reached the apple, the electrons in your bullet would have scattered, dispersing the energy — remember, like charges repel each other.

Bolts from the blue are positively charged, but as they travel some 10 miles through a cloud, they remain compact — about the width of a finger, and powerful.

“We’re not sure how nature keeps similarly charged electrons together for miles in the atmosphere,” Rassoul says.

He theorizes that lightning may travel in packets of electrons that generate a chain reaction of new packets along the way, like dominoes. Rassoul likens the theory to the concept of a generational star ship: The mission would launch from Earth with generation one, but once you reach, say, Proxima Centauri, it’s an entirely new group of people who reach the destination.

“It’s beautiful on paper, but we don’t know how to show it in the lab,” says Rassoul.

Where Does It Strike?

“Twenty-seven percent of the time, depending on conditions, the shorter object is hit by lightning rather than the tall object,” says Rassoul. Consider that all-too-common myth about lightning officially dead.

So what determines where lightning will strike, or what researchers call attachment? As you may have guessed, they’re still trying to figure that out, too.

Lightning begins with the development of a step leader, when excess electrons at the bottom of a storm cloud start racing through the air toward the ground. As they push down, the positive charge on Earth’s surface increases. The excess positive charges make their way up through buildings, cell towers — you — and into the air. These are called streamers.

And when streamer and leader meet — bang!

That much makes sense, but what isn’t clear is why a 6-foot-tall man can send a streamer higher into the air than a 100-foot cell tower, even if he’s standing right next to it.

“Sometimes objects change electrical potential so much, they project their positive charge higher than a tower,” says Rassoul. “But why am I sending such a long streamer up there? Again, none of these questions have been answered.”

Eyes on the Skies

Figuring out the mechanisms of lightning could increase our predictive capabilities and improve safety — and these are just three of many lightning mysteries. To probe lightning’s secrets, Rassoul’s team is using ultra-slow-motion cameras, inducing strikes with rockets, and using theoretical models and simulations to arrive at new insights.

Over the next several years, no doubt, work by the Florida Tech team and other scientists around the world will yield a better understanding of the power in our skies.

CATEGORIZED UNDER: Environment, Top Posts

Extinction Looms for Easter Island’s Only Remaining Native Species

By Nathaniel Scharping | July 19, 2016 12:58 pm

Jut Wynne at Rano Kao Volcano conducting reconnaissance for the cliff work to take place in August. (Credit: Rafael Rodriguez Brizuela)

On Easter Island, isolated in the middle of the vast Pacific Ocean, ten species of near microscopic insects are all that remain of the island’s native species — at least for now.

Hidden in volcanic caves that dot the island, the endemic insects of Rapa Nui eke out an existence in an increasingly imperiled habitat. Their ancestral homes, fragile gardens of moss and ferns, are endangered by tourists flooding into the tiny island, and hordes of invasive species threaten to crowd them out. The island may have been immortalized by its iconic Moai, monolithic stone statues standing some 40 feet tall, but its most important inhabitants are almost too small to be seen. Read More

CATEGORIZED UNDER: Environment, Living World, Top Posts

Earth’s Biodiversity Has Fallen Below ‘Safe’ Levels? Ecologists Disagree

By Bridget Alex | July 14, 2016 5:12 pm

(Credit: Markus Gann/Shutterstock)

A new paper reports that over half of Earth’s land area has suffered biodiversity loss beyond “safe limits.”

The study, released Thursday in Science, compiles a global dataset of biodiversity change and compares it to human land use patterns. The analysis shows that 58 percent of Earth’s land, which is home to 71 percent of the human population, has surpassed a recently proposed safe limit for biodiversity loss, beyond which ecosystems may no longer support human societies.

While the news sounds dire, other ecologists contend that the very notion of setting “safe limits” is a danger in itself, and criticize this line-in-the-sand approach to assessing the planet’s ecological health. In fact, critics say setting a limit may do more harm than good. Read More

CATEGORIZED UNDER: Environment, Top Posts

How I Helped Turn Carbon Dioxide into Stone

By Dom Wolff-Boenisch, Curtin University | June 9, 2016 5:15 pm

Iceland’s geothermal power plants are an ideal place to test pumping carbon dioxide underground. (Credit: Dom Wolff-Boenisch)

To halt climate change and prevent dangerous warming, we ultimately have to stop pumping greenhouse gases into the atmosphere. While the world is making slow progress on reducing emissions, there are more radical options, such as removing greenhouse gases from the atmosphere and storing them underground.

In a paper published today in Science my colleagues and I report on a successful trial converting carbon dioxide (CO₂) to rock and storing it underground in Iceland. Although we trialled only a small amount of CO₂, this method has enormous potential. Read More

CATEGORIZED UNDER: Environment, Top Posts

The Doomsday Clock in Fiction and Reality

By David Warmflash | May 18, 2016 7:00 am
the doomsday clock is set at three minutes before midnight.

(Credit: Bank Artist/Shutterstock)

A nuclear-armed Pakistani aircraft crashes just over the Indian border and the situation is about to spiral out of control. In Washington D.C., nuclear physicists and geopolitical analysts belonging to the Bulletin of the Atomic Scientists are meeting to decide whether to advance the “Doomsday Clock” ahead by two minutes.

The Doomsday Clock is a symbolic representation of the level danger on planet Earth, and moving it ahead two minutes would take it to two minutes before midnight — two minutes before the end. This fictional scenario played out on a recent episode of Madam Secretary, but the Clock has been used as a snapshot of the dangers we face for well over five decades. But how do the hands on the Clock tick?  Read More

CATEGORIZED UNDER: Environment, Technology, Top Posts

The Myth of the Virgin Rainforest

By Karen Coates | May 6, 2016 10:23 am

The modest village of Bario in the Kelabit Highlands hosts a school that offers surrounding communities educational opportunities—and brings them into contact with forces that threaten to radically alter their culture. (Credit: Samantha Elsie Jones)

(This post originally appeared in the online anthropology magazine SAPIENS. Follow @SAPIENS_org on Twitter to discover more of their work.) 

The little village of Pa Lungan sits in a grassy clearing, high in the hills of Malaysian Borneo, in a region called the Kelabit Highlands. The people here—a few dozen—belong to the Kelabit tribe, one of more than 50 Indigenous groups living on Asia’s largest island. They have sturdy wooden homes with slat glass windows, metal roofs, kitchen sinks, and TVs. Generators and solar panels power a few lightbulbs, laptops, and mobile phones (typically used to play music and games). Most households have a kitchen garden, an outdoor toilet, a cold-water shower, and a laundry line. A patchwork of coops and fences keeps chickens and buffalo in check. Just beyond these homes and yards lie rice fields fed by mountain waters and hemmed in by trees. It’s a tidy, orderly life in Pa Lungan—and it’s an easy walk to some of the most biologically diverse rainforests on Earth. Read More

CATEGORIZED UNDER: Environment, Top Posts
MORE ABOUT: forest

How to Harvest Terawatts of Solar Power on the Moon

By David Warmflash | April 22, 2016 1:03 pm

(Credit: Shimzu)

Planet Earth isn’t the most ideal place for solar power to thrive. Sunsets and weather afford solar panels a significant amount of downtime.

But there’s a place not too far from here where the sun never stops shining.

A handful of researchers, and more recently the Japanese corporation Shimizu, have been gearing up to develop solar power on the moon.

Shimizu took off with the idea in 2013 in the aftermath of Japan’s 2011 Fukishima accident, which produced a political climate demanding alternatives to nuclear power plants. Shimizu’s plans call for beginning construction of a lunar solar power base as early as 2035. The solar array would be 250 miles wide and span the lunar circumference of 6,800 miles. They’re calling it the Luna Ring. Read More

Unintended Consequences: The Sinister Side of Species Protection

By Susan Brackney | April 6, 2016 1:49 pm

One of 13 bald eagles found dead on a farm in Maryland. (Credit: Maryland Natural Resources Police)

There’s something dark at work when it comes to certain human-animal interactions.

A recent report from the Ecological Society of America admits that calling attention to plants and animals in need of special protections can actually result in “perverse consequences,” ultimately putting some species in harm’s way—even in the face of stiff penalties.

Killing a bald eagle is a federal offense punishable by up to one year in prison and a $100,000 fine. “A subsequent conviction under the Bald and Golden Eagles Act, raises the maximum penalty up to two years in prison and a $250,000 fine,” says Neil Mendelsohn, assistant special agent in charge at the Northeast Regional Office of the U.S. Fish and Wildlife Service.

He’s currently investigating the mysterious deaths of 13 bald eagles discovered in Federalsburg, Maryland in late February. The reward for information now stands at $25,000. Necropsies show the birds didn’t die of disease or natural causes, and officials are keeping mum so far—other than to say human intervention is suspected.

Why do some people target and kill protected animals? It’s a question scientists have asked before. Read More

CATEGORIZED UNDER: Environment, Living World, Top Posts

South Asia’s Vultures Back From the Brink

By William H. Funk | April 4, 2016 8:00 am

A long-billed (Indian) vulture (Credit: Vaibhavcho, CC)

Unlovely, unloved and utterly necessary for controlling disease and stabilizing ecological health, vultures are under attack around the world.

In Africa, populations of a half-dozen species are nearing collapse due to a combination of human-caused killings ranging from poaching for bushmeat and religious objects to the deliberate poisoning of poached elephant carcasses to destroy the circling scavengers.

In southern Asia, and particularly in India, the chief villain has been a nonsteroidal anti-inflammatory drug called diclofenac, widely used to treat arthritis symptoms in cattle and water buffalo. Diclofenac causes acute kidney failure in vultures feeding from the carcasses of recently treated livestock, and has caused catastrophic declines in all three species of vulture populations in the genus Gyps, including the white-rumped, the long-billed and the slender-billed vultures; the first of these listed species declined by more than 99.9 percent between 1992 and 2007, with tens of millions of individuals dying across South Asia. Read More

CATEGORIZED UNDER: Environment, Living World, Top Posts

Why Nuclear Fusion Is Always 30 Years Away

By Nathaniel Scharping | March 23, 2016 11:50 am

The Joint European Torus tokamak generator, as seen from the inside. (Credit: EUROfusion)

Nuclear fusion has long been considered the “holy grail” of energy research. It represents a nearly limitless source of energy that is clean, safe and self-sustaining. Ever since its existence was first theorized in the 1920s by English physicist Arthur Eddington, nuclear fusion has captured the imaginations of scientists and science-fiction writers alike.

Fusion, at its core, is a simple concept. Take two hydrogen isotopes and smash them together with overwhelming force. The two atoms overcome their natural repulsion and fuse, yielding a reaction that produces an enormous amount of energy.

But a big payoff requires an equally large investment, and for decades we have wrestled with the problem of energizing and holding on to the hydrogen fuel as it reaches temperatures in excess of 150 million degrees Fahrenheit. To date, the most successful fusion experiments have succeeded in heating plasma to over 900 million degrees Fahrenheit, and held onto a plasma for three and a half minutes, although not at the same time, and with different reactors.

The most recent advancements have come from Germany, where the Wendelstein 7-X reactor recently came online with a successful test run reaching almost 180 million degrees, and China, where the EAST reactor sustained a fusion plasma for 102 seconds, although at lower temperatures.

Still, even with these steps forward, researchers have said for decades that we’re still 30 years away from a working fusion reactor. Even as scientists take steps toward their holy grail, it becomes ever more clear that we don’t even yet know what we don’t know. Read More

CATEGORIZED UNDER: Environment, Technology, Top Posts
MORE ABOUT: energy

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