September 2017 on EARTH Magazine

Can preserved proteins reveal paint-by-numbers plumage?

Thu, 12 Oct 2017 12:20:11 -0400

Some of the most compelling dinosaur fossils are those found with clearly defined feathers. Feathers may seem fragile and unlikely to be preserved, but in fact they’re composed of durable keratin, one of the toughest natural proteins. Additionally, some fossil feathers unearthed are speckled with tiny black dots, which, according to different studies, could be remnants of either bacteria or melanosomes. Melanosomes are organelles that produce and store melanin, the main source of pigment in feathers. If melanosomes are indeed preserved in some ancient fossils, they could reveal information about dinosaur coloration and plumage — and represent further evidence of preserved proteins in dinosaurs.

Less-developed countries with high climate risk need better access to weather and climate data

Fri, 22 Sep 2017 10:28:29 -0400

Rising seas, more persistent droughts and more frequent severe weather events are predicted to occur in the coming decades as the planet continues warming. In a new study, researchers who analyzed spending internationally on weather and climate information services (WCIS) suggest that access to reliable WCIS is becoming more vital for communities and governments looking to assess their vulnerability and to safeguard people and property amid changing climates.

Neolithic farmers impacted sedimentation

Mon, 18 Sep 2017 14:45:40 -0400

People have been affecting the Dead Sea Basin since Neolithic times. Credit: EvgeniT, CC BY-SA 3.0.

The Neolithic Revolution, also known as the Agricultural Revolution, started in the Middle East about 11,500 years ago when people moved away from nomadic hunting and gathering toward more settled agricultural communities where they raised livestock and cultivated crops. In a new study of the Dead Sea Basin, researchers found that this turning point may also mark the first time that humans made a measurable impact on sedimentation rates.

Geomedia: Radio: "Big Picture Science" aptly named

Mon, 18 Sep 2017 14:41:31 -0400

The weekly "Big Picture Science" radio show crew (from left to right) includes Co-Host Seth Shostak, former intern Jay Weiler, Operations Manager Barbara Vance, Producer Gary Niederhoff, and Co-Host Molly Bentley. Credit: Big Picture Science/SETI.

Titles can sometimes be a hard thing to live up to, but “Big Picture Science,” a weekly radio program broadcast on about 100 stations nationwide, delivers on its name. The show, which cleverly covers everything from a study of frogs in pants to efforts to create a compassionate computer, lives up to its mission of presenting a wide-angle view of science and technology.

Down to Earth With: Paleobiologist Gregory Erickson

Mon, 18 Sep 2017 14:37:02 -0400

Gregory Erickson is a professor of anatomy and vertebrate paleobiology at Florida State University in Tallahassee, Fla. Credit: Gregory Erickson.

As an undergraduate at the University of Washington, Gregory Erickson wasn’t sure what he wanted to do. He started out as an engineering major, then dabbled with getting a degree in wildlife management. In 1986, having taken numerous science courses, he happened to compare notes with his best friend, a geology major, and realized he was just a few courses shy of obtaining a geology degree himself. Eager to finish college, Erickson signed up for a class in vertebrate paleontology focusing on dinosaurs — a decision that ultimately changed his life.

Cassini's legacy after two decades

Thu, 14 Sep 2017 18:51:59 -0400

Cassini captured this view of Saturn and its rings, about 1.4 million kilometers away from the planet, using a combination of images. Credit: NASA/JPL-Caltech/Space Science Institute.

On Sept. 15, 2017, at 4:55 a.m. PT, scientists on Earth received the last transmission from the Cassini spacecraft. It descended into Saturn’s atmosphere at 122,500 kilometers per hour, which caused it to melt, thereby ensuring that Saturn’s moons Titan and Enceladus would remain protected from possible contamination by any errant Earth microbes. Cassini scientists had considered other options for the spacecraft’s end, including leaving it to float endlessly in space or parking it in orbit around Saturn. But ultimately, they chose to have it descend into Saturn’s atmosphere after deciding the data that could be returned from the descent were more valuable than any further data it might obtain by remaining in space. Scientists will make discoveries from these data for decades to come.

New map of Arctic geology published

Thu, 14 Sep 2017 12:54:40 -0400

A new map of Arctic resources highlights diamond and metal deposits. Credit: Geological Survey of Norway.

At first glance, it might seem there’s little more to the Arctic than frozen tundra, ice and seawater, but the top of the world is home to some unique geology and an impressive array of mineral resources. A new project led by the Geological Survey of Norway (GSN) has compiled all existing geologic data about the Circum-Arctic region into a book, database and interactive map.

How the Arctic became salty

Thu, 14 Sep 2017 12:48:13 -0400

During the Eocene, the Arctic Ocean was a giant freshwater lake fed by rivers and ice melt. Today, it's salty and ice-covered much of the year. Credit: NASA.

The Arctic Ocean hasn’t always been as salty as other oceans. In the Eocene, between 56 million and 34 million years ago, the water surrounding the North Pole — freshened by melt from sea ice and river runoff — was cut off from the Atlantic and Pacific oceans by land bridges. At some point, plate tectonic processes opened the North Atlantic, submerging the land bridges and allowing saltwater to pour into the Arctic, but the timing and details of these events are largely unknown. New research suggests a tipping point may have been reached as one particular land bridge submerged far enough below the ocean surface.

Comment: The Anthropocene: Foregone or premature conclusion? Examining the ethical implications of naming a new epoch

Thu, 14 Sep 2017 12:15:59 -0400

Credit: Kevin Walsh, CC BY 2.0.

The scientific movement to declare a new geological epoch called the Anthropocene has received a lot of attention in the popular press. There seems to be an impression that designating an Anthropocene Epoch is a cool or compelling way to recognize that human societies have caused recent and ongoing global climate change, as well as other systemwide impacts on Earth, including acidification of the oceans, widespread species endangerment and landscape changes. I have even heard it said that the idea of the Anthropocene is a way to acknowledge and begin facing our personal and collective responsibilities with respect to those impacts.

Comment: Providing resources for future generations - Technical and human challenges

Thu, 14 Sep 2017 12:06:06 -0400

Credit: RFG 2018.

Earth is a remarkable planet, providing us with a comfortable place to live and the energy, minerals and water to sustain our societies. Geoscientists understand the dynamic processes within, and at the surface of, our rocky planet that shape our unique home. Plate tectonics and related processes have operated throughout much of Earth’s history, leading to repeated amalgamation and breakup of supercontinents; the building and erosion of mountain ranges thousands of kilometers long; the constant delivery of massive quantities of sediment from the continents into adjacent sedimentary basins; and disruptive and hazardous events such as earthquakes, volcanic eruptions and violent storms. These and other geological processes have moved and concentrated metals, minerals, hydrocarbons and water. The resulting concentrations of natural resources were so obvious that ancient humans recognized and exploited them beginning more than 10,000 years ago.

Glass shards reveal a fiery history in Ethiopia

Thu, 14 Sep 2017 11:51:18 -0400

Scientists drilled below Lake Ashenge, on the western border of the Afar Triangle, for evidence of past eruptions. Credit: Catherine Martin-Jones.

Chains of volcanoes and a lava lake pepper the landscape of the Afar Triangle in northeastern Ethiopia, where eruptions and earthquakes are byproducts of the rifting that is literally ripping Africa apart, but recent eruptions have been docile. Now, scientists studying ash deposits from the last 40,000 years are showing that dangerous, explosive eruptions present an ongoing hazard, striking the region every 1,000 years on average.

Volcanism triggered end-Triassic extinction

Thu, 14 Sep 2017 11:47:17 -0400

These continental sedimentary layers in Morocco spanning the end-Triassic mass extinction event were analyzed for mercury content in a new study. Credit: Jessica Whiteside.

The end-Triassic mass extinction exterminated up to three-quarters of all species on land and in the oceans 201 million years ago. This die-off opened up ecological niches and allowed for, among other changes, dinosaurs to diversify and spread across terrestrial ecosystems during the rest of the Mesozoic. Volcanism has long been implicated in the extinction, but whether it had a major impact on the planet at the time has remained unclear. In new research, scientists observed elevated mercury concentrations in extinction-aged rocks from around the world. Because volcanism is the main nonanthropogenic source of mercury in the environment, the findings suggest that volcanic activity was likely the main extinction trigger at the end of the Triassic.

Jerusalem tower facelift reveals it's 1,000 years younger

Thu, 14 Sep 2017 11:44:20 -0400

The base of the Spring Tower built to protect Jerusalem's Gihon Spring is 7 meters thick, constructed from boulders and sediment. Credit: Weizmann Institute of Science.

Jerusalem is one of the oldest cities in the world, dating back to at least 2400 B.C. Downhill from the heart of the city is Gihon Spring, a year-round natural fount that was likely the primary water source for the ancient city. Defensive fortifications built around the spring, known as the Spring Tower, were originally dated to the Middle Bronze Age, around 1700 B.C., but a new study reveals the tower could be as much as 1,000 years younger.

Making oxygen with MOXIE

Tue, 12 Sep 2017 13:44:40 -0400

NASA's Mars 2020 Rover will carry a variety of instrument payloads, including MOXIE (center of the illustration). Credit: NASA/JPL-Caltech.

The MOXIE (Mars OXygen In-situ resource utilization Experiment) instrument on NASA’s 2020 rover is designed to demonstrate technology that can generate oxygen from carbon dioxide in the Martian atmosphere. Scaled-up versions of the technology could one day be used to produce the large amounts of fuel needed to boost rockets back off the planet’s surface, as well as to create breathing oxygen for human settlements.

A great time to land on Mars

Tue, 12 Sep 2017 13:41:52 -0400

Measurements by Curiosity at Gale Crater over two Martian years show that the highest atmospheric pressures on Mars occur during southern hemisphere spring and autumn (northern autumn and spring, respectively). Credit: NASA/JPL-Caltech/CAB(CSIC-INTA).

The 2020 window represents an especially good opportunity for missions looking to reach the Martian surface because of favorable environmental conditions on the planet early in 2021 when the spacecraft will arrive. The elliptical shape of Mars’ orbit means that the planet is, at times, much closer to or farther from the sun, so the amount of sunlight hitting the planet varies dramatically through the Martian year. Meanwhile, the tilt of Mars’ axis, as on Earth, leads to a progression of seasons as the orientations of the northern and southern hemispheres with respect to the sun change regularly and oppositely. The combination of Mars’ orbit and tilt drives an annual cycle of swings in atmospheric pressure of up to about 25 percent as carbon dioxide freezes out of, or sublimes into, the atmosphere.

Mars class of 2020: A diverse group of missions takes aim at the Red Planet

Tue, 12 Sep 2017 13:34:32 -0400

Credit: K. Cantner, AGI.

About every 26 months, the positions of Earth and Mars in their respective orbits align for a few weeks such that spacecraft can take the shortest possible route to the Red Planet. A shorter trip means less fuel — and consequently less mass — to carry, as well as less time for mishaps to occur in transit. These are compelling factors for cost- and weight-conscious mission planners, so it’s during these brief, roughly biennial launch windows that space agencies have typically sent spacecraft to Mars.

Where on Earth? - September 2017

Wed, 30 Aug 2017 17:05:10 -0400

Click to enlarge photo.

Clues for September 2017:

The view of this valley — from an overlook near the western tip of the Olokele Plateau — stretches nearly 5 kilometers out and 1.2 kilometers down to a shoreline that shares its name with the thin, fluted layers of basalt flanking the valley.
Behind the overlook lies the highest swamp on Earth, which receives 1.8 meters of rainfall annually.
A NASA geophysical observatory at the entrance of a nearby state park has been used to track manned spacecraft splashing down in the Pacific.

Getting there and getting around Bolivia's Antiplano

Wed, 16 Aug 2017 12:30:59 -0400

Traveling to Lake Titicaca and other parts of Bolivia can be quite an adventure. Credit: Terri Cook and Lon Abbott.

“Bolivia’s main gateway, El Alto International Airport (LPB), is located 13 kilometers southwest of the country’s capital, La Paz. It hosts regular, year-round flights to and from major destinations in South America, including Lima and Cuzco, Peru, Santiago, Chile, and Buenos Aires, Argentina, as well as connecting flights to Miami on American Airlines and Los Angeles, Washington, D.C. (Dulles) and Orlando, Fla., on Avianca. Several regional airlines, including Boliviana de Aviación (BoA) and Amaszonas, offer multiple flights daily from La Paz to Uyuni. The hour-long flight typically costs about $150 one way. We found the South American carriers to be extremely efficient; it’s important to arrive at the airport two hours in advance because the flights often depart early!

Travels in Geology: Sky-high adventure on Bolivia's Altiplano

Wed, 16 Aug 2017 12:20:27 -0400

Green Lagoon (Laguna Verde) is a highly concentrated salt lake located in the southwest of the Eduardo Avaroa Andean Fauna National Reserve at the foot of the Licancabur Volcano, Sur Lipez Province, Bolivia. The green-turquoise color of the water is due to suspension of arsenic and other minerals. Credit: ©iStockphoto.com/thomaslusth.

Nestled between two ranges of the rugged Andes Mountains, the Altiplano is a vast, windswept plateau that stretches more than 900 kilometers from southern Peru to northern Argentina. Most of this arid upland, which averages about 3,750 meters in elevation, sits in western Bolivia, where its surface is dotted with a series of stunning natural attractions. From the snow-white crystals of the world’s largest salt flats and flocks of pink flamingos in a brick-red lake to the startlingly azure waters of Lake Titicaca, the planet’s highest navigable lake, the Altiplano offers spectacular, vividly colored vistas for intrepid travelers. You could easily spend a month exploring this region, or get a tantalizing, week-long taste as part of a bigger South American journey, as we did in 2016, when we started in Peru and ended in Patagonia.

Geologic Column: Musings on the autumn equinox

Wed, 16 Aug 2017 11:35:21 -0400

Panaoramic color photograph made at Fredonian Nature Center in Shirley, Massachusetts, at the fall equinox, September 22, 2002. Credit: Bob Burkhardt, CC BY 3.0

Last month, many of us in the U.S. celebrated a relatively rare event — a full solar eclipse. That event, and the fact that the metal roof of my ranch house in California’s Santa Ynez Valley has started resonating with the thunk of raining acorns, got me thinking about our annual trip around the sun and the impending fall equinox.

Comment: A pitch to study BREW: The beer-renewable energy-water nexus

Wed, 16 Aug 2017 11:31:36 -0400

K. Cantner, AGI

Over the past few years, the food-energy-water nexus has become trendy for multidisciplinary systems-level research as it ties together three of the most critical elements of a modern society. Food security, energy security and water security are all inextricably linked, and the demand for all three is increasing. In recent years, the U.S. National Science Foundation has set aside $72 million to support research that spans these three topics. While I applaud this research path, I would like to suggest another topic that also warrants dedication from researchers: the beer-renewable energy-water nexus, or BREW. And I would further like to be the first to volunteer to personally collect field data at pubs and breweries nationwide.

Down to Earth With: Paleontologist Lisa D. White

Wed, 16 Aug 2017 11:19:12 -0400

Lisa White, assistant director of Education and Public Programs at the University of California Museum of Paleontology, at the 2016 meeting of the Society of Vertebrate Paleontology. Credit: Thea Boodhoo.

As a college student at San Francisco State University, Lisa D. White’s first choice of major was photography. She was drawn to landscapes, and dreamed of becoming “the black female Ansel Adams,” she tells me, surrounded by fossils. We’re in a lab at the University of California Museum of Paleontology (UCMP) in Berkeley, where she is assistant director of Education and Public Programs. She is also a micropaleontologist, and from 1990 until joining UCMP in 2012, she was professor of geology and later associate dean at San Francisco State University.

Benchmarks: September 23, 1806: Lewis and Clark's Corps of Discovery returns from the West

Tue, 15 Aug 2017 15:14:49 -0400

Captains Meriwether Lewis and William Clark, who, from 1804 to 1806, led the expedition of the Corps of Discovery to explore the United States' newly acquired territory. Credit: both: public domain.

It’s been called the greatest camping trip of all time. Statues, counties, waterways, mountains, military vessels, and even two colleges bear the names of the journey’s leaders. Their journals are among our greatest national treasures, and their adventures have inspired generations of explorers. Two hundred and eleven years ago this month, Captains Meriwether Lewis and William Clark and their 31-man Corps of Discovery returned to St. Louis, the frontier town where they had started their journey 28 months and nearly 13,000 kilometers of wilderness earlier on May 14, 1804.

Geomedia: Books: Exploring space is risky business

Tue, 15 Aug 2017 15:05:25 -0400

"Mankind Beyond Earth: The History, Science, and Future of Human Space Exploration," Claude A. Piantadosi, Columbia University Press, 2015, ISBN-13: 978-0231162432.

Claude A. Piantadosi portrays the history and future of space exploration through the lens of space medicine, which reminds us of the many threats to the human body that await as we venture away from our planet.

Ice (Re)Cap: September 2017

Tue, 15 Aug 2017 14:33:37 -0400

River icings, like this 5-meter-thick one on the Echooka River in Alaska in 1972, are large masses of ice that form each winter in and around rivers across the Arctic. New research suggests river icings in Alaska and Canada are melting earlier in the year. Credit: U.S. Geological Survey.

From Antarctica to the Arctic; from polar caps, permafrost and glaciers to ocean-rafted sea ice; and from burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

End of ice age may have been too wet for megafauna

Tue, 15 Aug 2017 14:30:11 -0400

Large ice-age herbivores, as imagined in this artist's rendition, might have been driven to extinction by rising moisture levels that caused semi-arid grassland areas to shrink. Credit: K. Cantner, AGI.

Between 15,000 and 11,000 years ago, dozens of ice-age megafauna species went extinct. Various causes, from climate-driven habitat changes to overhunting to extraterrestrial impacts, have been cited for these extinctions. But new research looking at fossils of large herbivores such as bison, horses and llama supports the idea that a worldwide uptick in moisture was a main driver of the extinction trend.

Dehydrated sediment layer made Sumatra quake stronger

Tue, 15 Aug 2017 14:25:42 -0400

Map showing the rupture zone of the magnitude-9.1 Sumatra quake in December 2004, as well as the tsunami inundation zone and locations where scientists pulled up sediment cores that are adding to the understanding of the massive quake. Credit: K. Cantner, AGI.

Subduction zones are notorious for unleashing great earthquakes and tsunamis, such as the 2004 magnitude-9.1 Sumatra quake that caused shaking and inundations that killed more than 250,000 people and left millions more homeless. However, despite the dangerous reputations of subduction zones, their hazards are still often underestimated. New research reveals how sediments in the Sumatra Trench may have contributed to producing an even bigger earthquake and tsunami than hazard forecasts had estimated.

Reconstructing ancient oxidant levels and their climatic effects

Tue, 15 Aug 2017 14:23:14 -0400

Credit: Sara E. Pratt.

Oxidants in the troposphere, such as ozone and hydroxyl radicals, influence the life spans of other atmospheric components, including pollutants and greenhouse gases like carbon monoxide and methane. But how the abundance of tropospheric oxidants varies as climate changes is poorly understood. Part of the challenge is that these oxidants are too reactive to be preserved in paleo-records, such as ice cores.

Asymmetrical fossil feathers fill in timeline of flight

Tue, 15 Aug 2017 14:19:18 -0400

To get off the ground and evolve into flying birds, dinosaurs got a lift from asymmetrical feathers, which are more aerodynamic than symmetrical feathers. The discovery of a new species of asymmetrically feathered dinosaur in northeastern China from the Early Cretaceous is helping fill in the timeline of adaptations that led to flight.

T. rex's bone-crushing bite

Tue, 15 Aug 2017 14:16:40 -0400

T.rex (specimen AMNH 5027) at American Museum of Natural History. Credit: J.M. Luijt CC BY-SA 2.5 nl.

In a landscape rife with fearsome predators, Tyrannosaurus rex carved out a bone-crushing niche. New research analyzing the force generated by T. rex’s massive jaws found that the terrible tyrant’s bite could exert a pressure of more than 30,300 kilograms per square centimeter (431,000 pounds per square inch): a world record.

When schools shake: Keeping students and teachers safe during earthquakes

Fri, 11 Aug 2017 14:05:24 -0400

This school in Nepal collapsed during the 2015 magnitude-7.8 Gorkha earthquake. Blue metal schooldesks can be seen crushed between the pancaked floors. No students were present because the quake occurred on a Saturday. Credit: both: Anne Sanquini, GeoHazards International.

When the magnitude-7.8 Gorkha earthquake rocked Nepal on April 25, 2015, it destroyed 19,000 classrooms and damaged more than 30,000 others. The quake — in which nearly 9,000 people died and 22,000 others were injured — struck on a Saturday, when schools in Nepal are not in session. Still, more than 500 students and teachers died in collapsing school buildings, according to data from the Nepal Ministry of Education. Had those damaged classrooms been filled with students and teachers, the death toll would have been far higher.

Coatings may prevent pipeline clogs

Fri, 11 Aug 2017 14:01:14 -0400

Clogs caused by the formation of gas hydrates are a major concern for oil and gas pipeline operators. Water-repellent films coating the inside of pipes could prevent hydrate formation. Credit: Luca Galuzzi, CC BY-SA 2.5.

When ice forms in household water pipes, blockages and expansion can cause the pipes to burst. Similar problems can arise in the transportation of oil and gas when ice-like substances called gas hydrates build up inside pipelines — an issue traditionally mitigated by insulating pipes or by using antifreeze additives. But in a new study published in the journal ACS Applied Materials and Interfaces, researchers report an alternative solution: specialized coatings for the inside of oil and gas pipes that prevent hydrate buildups and clogs. The coatings could prove more reliable than the usual approaches, but whether the method can be applied cost-effectively on a large scale is uncertain.

A mammoth king: Was the legend of King Hygelac in "Beowulf" inspired by a fossil find?

Thu, 10 Aug 2017 14:35:44 -0400

Could woolly mammoth remains, found in the area where legend suggests King Hygelac and his Viking raiders were buried, have been misidentified as human bones in the eighth century? Credit: Hans Wildschut, courtesy of North Sea Fossils.

As far-fetched as it may seem, the death of a woolly mammoth thousands of years ago on an island in the Rhine-Meuse River Delta, near present-day Rotterdam in the Netherlands, could have led, millennia later, to the monsters and characters of “Beowulf.” The road from pachyderm to poem has many twists and turns, and following it calls for some literary and scientific sleuthing.

Baby Louie dinosaur fossil gets a formal name

Thu, 10 Aug 2017 11:33:59 -0400

Top: An illustration of a Beibeilong embryo and egg fossil, with reconstructions of the skeleton and embryo to the right. Bottom: An artist's rendition of the nesting parents. Credit: both: Zhao Chuang.

A baby dinosaur found fossilized with a clutch of eggs in China in the 1990s has finally been identified as an embryo from a new species of giant oviraptorosaur, according to a study in Nature Communications. The specimen, nicknamed “Baby Louie” and once featured on the cover of National Geographic, has been formally classified as a caenagnathid oviraptorosaur named Beibeilong sinensis, which translates to “Chinese baby dragon,” by Hanyong Pu of the Henan Geological Museum in Zhengzhou, China, and colleagues.

Earthquakes make volcanoes more — and less — gassy

Thu, 10 Aug 2017 11:30:57 -0400

Turrialba Volcano in Costa Rica showed an increase in sulfur dioxide emissions after earthquakes. Credit: ©iStockphoto.com/piratedub.

Triggering of volcanic emissions by earthquakes has been observed since antiquity. The Roman naturalist and philosopher Pliny the Elder proposed the link as early as A.D. 77, and in “The Voyage of the Beagle,” Charles Darwin wrote about inland eruptions in Chile closely following an offshore earthquake in 1835. More recent statistical studies show that after large earthquakes, volcanic activity around the world increases. But the lack of robust monitoring equipment at most volcanoes has made it hard to quantify the relationship. In a new study, scientists demonstrate how satellites can be used to track changes in sulfur dioxide emissions from volcanoes after seismic events, offering a potential way to study the often elusive link between seismicity and volcanism.

Transylvanian ice cave reveals European winter climate record

Thu, 10 Aug 2017 11:28:17 -0400

Over the last 10,000 years, water dripping into a cave in Transylvania has frozen into one of the largest and oldest cave glaciers in the world. Today, the Scărișoara Ice Cave in central Romania preserves one of the longest ice records on Earth, a boon for climate researchers seeking to study how Europe’s climate has fluctuated during the Holocene.

Dust influences pollution levels in eastern China

Thu, 10 Aug 2017 11:21:24 -0400

Smog blankets eastern China in this satellite image from October 2010. Credit: NASA.

Air pollution often enshrouds cities in eastern China in a thick haze that impairs visibility and causes respiratory health problems. Emissions from human activity are mainly to blame, but climate researchers now report that natural forces — namely, dust kicked into the air by wind — can also exert a strong control over how much pollution persists in the air.

Young Costa Rican lavas might reflect pockets of primordial mantle

Thu, 10 Aug 2017 11:18:53 -0400

Komatiites are commonly found in Archean deposits, but a much younger flow found in Costa Rica may unlock some secrets about Earth's mantle. Credit: Esteban Gazel.

During the Archean, between 4 billion and 2.5 billion years ago, Earth’s super-heated young mantle produced a unique type of lava known as komatiite. In a new study published in Nature Geoscience, researchers looking at 90-million-year-old komatiites in Costa Rica — by far the youngest komatiites ever found — suggest the modern mantle may still harbor pockets of intense heat reminiscent of early Earth.

Why meteors snap, crackle and pop

Wed, 09 Aug 2017 16:40:02 -0400

A meteor streaks through the night sky over South Australia. Credit: C m handler, CC BY-SA 3.0.

Keen-eared observers sometimes report hearing popping, whistling or buzzing at the same time they see meteors pass far overhead, a perplexing phenomenon called the electrophonic effect. What causes the effect — or if it’s even real — has been discussed for centuries; famed astronomer Edmond Halley is said to have dismissed it as a figment of people’s imaginations. In a new study in Geophysical Research Letters, researchers suggest that not only is it real, but that it is caused by radio waves induced by meteors and converted to sound waves near Earth’s surface.

Northeast and Midwest U.S. projected to warm faster than national average

Fri, 16 Jun 2017 16:18:28 -0400

The Northeast, including Boston, is projected to warm more quickly over the next few decades than the contiguous U.S. as a whole, according to a recent study. Credit: bobwright, CC0

The U.S. Northeast and Midwest will warm quickly in the coming decades compared to national and global averages, reaching established temperature benchmarks sooner than most of the rest of the country, and the world, according to recent research published in PLOS ONE.