Category: Environment

How Vulnerable Are Societies to Collapse?

By Jim O'Donnell | September 28, 2017 12:28 pm
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Research findings on three early Native American cultures from the southwestern United States show how each responded to environmental challenges in different ways that dramatically altered their people’s futures. (David Williams/SAPIENS)

Along the cottonwood-lined rivers of southwestern New Mexico and southeastern Arizona, the Mimbres people did something unique: By the year 1000, these farmers were producing stunning ceramics decorated with naturalistic images of fish, people, and rabbits, as well as magical creatures and elaborate geometric patterns. And then, rather abruptly, they stopped.

After roughly a century of higher than normal rainfall, the area the Mimbres inhabited suffered a powerful drought, as indicated by the archaeological record. Big game—already scarce—became even less abundant, and it became harder to grow the beans, corn and squash that the Mimbres relied on. By about 1150 the Mimbres were no longer making their signature pottery. Read More

CATEGORIZED UNDER: Environment, Living World, Top Posts

Lake Michigan Itself Is the Greatest Asian Carp Deterrent

By Eric Betz | September 22, 2017 3:31 pm
Asian carp jump from the water at the mouth of the Wabash River in Ohio. (Credit: U.S. Army Corps of Engineers/Todd Davis)

Asian carp jump from the water at the mouth of the Wabash River in Ohio. (Credit: U.S. Army Corps of Engineers/Todd Davis)

For years, people have been freaking out that Asian carp are about to invade the Great Lakes.

That concern seemed more real than ever this summer after an Illinois fisherman caught a carp in June less than 10 miles from Lake Michigan — beyond the barriers designed to keep them out.

These voracious fish have already decimated Midwestern rivers. They’re filter feeders who feast on plankton — the tiny plants and critters that prop up foodchains. And they eat lots of them. Adult Asian carp eat pounds of the stuff every day. Read More

CATEGORIZED UNDER: Environment, Top Posts

What’s Going On With the World’s Most Destructive Mud Volcano?

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Now abandoned, part of Sidoarjo town is entombed in mud metres thick. (Credit: sawerigading)

The world’s most destructive mud volcano was born near the town of Sidoarjo, on the island of Java, Indonesia, just over 11 years ago – and to this day it has not stopped erupting. The mud volcano known as Lusi started on May 29, 2006, and at its peak disgorged a staggering 180,000 cubic meters of mud every day, burying villages in mud up to 40 meters thick. The worst event of its kind in recorded history, the eruption took 13 lives and destroyed the homes of 60,000 people. But although the mud is still flowing more than a decade later, scientists are not yet agreed on its cause.

The debate is whether the eruption of Lusi was due to an earthquake several days previously, or down to a catastrophic failure of the Banjar Panji 1 gas exploration well that was being drilled nearby at the time. Given the huge impact of the volcano on the communities nearby and the fields that were their livelihoods, why are we still unsure of the cause? Read More

CATEGORIZED UNDER: Environment, Top Posts

What Would It Take to Wipe Out All Life on Earth?

An asteroid smacks into planet Earth.

(Credit: Shutterstock)

The first exoplanet was spotted in 1988. Since then more than 3,000 planets have been found outside our solar system, and it’s thought that around 20 percent of Sun-like stars have an Earth-like planet in their habitable zones. We don’t yet know if any of these host life – and we don’t know how life begins. But even if life does begin, would it survive?

Earth has undergone at least five mass extinctions in its history. It’s long been thought that an asteroid impact ended the dinosaurs. As a species, we are rightly concerned about events that could lead to our own elimination – climate change, nuclear war or disease could wipe us out. So it’s natural to wonder what it would take to eliminate all life on a planet. Read More

CATEGORIZED UNDER: Environment, Top Posts
MORE ABOUT: natural disasters

The Mother of All Apples Is Disappearing

By John Wenz | June 8, 2017 9:49 am
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You probably haven’t eaten this fruit before, but you may have one of its descendants in your house right now. (Credit: petrOlly/Flickr)

In the wilds of Kazakhstan, there’s an unassuming tree that bears an unassuming fruit. Like many plant species, development encroaches on its usual territory while climate change makes it harder for the tree to thrive and bear healthy yields of fruit.

You probably haven’t eaten this fruit before, but you may have one of its descendants in your house right now. After all, its children have more than 7,500 varieties in an assortment of colors and tastes and textures. Read More

CATEGORIZED UNDER: Environment, Top Posts
MORE ABOUT: plants

Energy Observer: Around the World on Renewables

By Dhananjay Khadilkar | February 2, 2017 11:58 am
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A computer-generated image of the Energy Observer in frigid waters. (Credit: Kadeg Boucher/Energy Observer)

For over two decades, 45-year-old, French documentary maker Jerome Delafosse has been diving into oceans the world over to film marine life, and he’s thrilled about his next expedition—above water. This spring, he will serve as chief explorer aboard the Energy Observer, a boat powered by the sun, wind and hydrogen. In a first-of-its-kind endeavor, Delafosse and his team plan to circumnavigate the globe over six years, visiting 101 ports in 50 countries, while relying entirely on renewable energy sources to reach their destinations.

Delafosse and his compatriot, 37-year-old Victorien Erussard, who is the boat’s captain, hope to renew the legend of this 30-meter-long, 13-meter-wide catamaran, which was built in 1982 and named Formule Tag. It won the Trophéé Jules Vernes for the team Enza New Zealand skippered by Sir Peter Blake. Currently, it’s being equipped with its new energy systems in the northwestern French port of Saint Malo. Read More

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

Lightning’s Strange Physics Still Stump Scientists

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

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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.

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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
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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
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(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
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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
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