Science & Technology
06 Aug 2015:
Mimicking Butterfly Wings Can
Improve Efficiency of Solar Energy Systems
Solar-concentrating photovoltaic systems can produce nearly 50 percent more power by mimicking the V-shaped wing
Cabbage white butterfly
formation certain butterflies exhibit before take-off, say researchers at the University of Exeter. The cabbage white butterfly warms its muscles before flight by placing its wings in the shape of a "V" to maximize the concentration of solar energy onto its thorax. This behavior, known as reflectance basking, increases the butterfly's thorax temperature by roughly 13 degrees F compared to flat wings, the researchers found. When reflective panels are arranged around a concentrating photovoltaic system in the same way, this wing-like configuration increases the power-to-weight ratio of the solar energy system by 17-fold, making it vastly more efficient, the researchers explain in the journal Scientific Reports
. The team showed that replicating the single layer of highly reflective scale cells found in the butterfly wings could also improve power-to-weight ratios of solar concentrators.
04 Aug 2015:
Study Finds Glaciers Melting
At Unprecidented Rates Around the Globe
Glaciers around the globe are melting at unprecedented rates, according to
an analysis of data spanning 120 years by researchers at
Rhone Glacier in Switzerland
the University of Zurich. The team compared glacier data collected between 2001 and 2010 with measurements, aerial and satellite photos, written accounts, and historical depictions from the previous century. On average, glaciers are currently losing between 0.5 and 1 meter of ice thickness each year, the researchers found — two to three times more than glaciers were losing on average in the 20th century. Although the team analyzed exact measurements from a few hundred glaciers, they say that field- and satellite-based observations of tens of thousands of glaciers around the world confirm their findings on a much larger scale. Intense ice loss over the past two decades has made glaciers unstable in many regions, the researchers say, and these glaciers will suffer further ice loss, even if the climate stabilizes.
31 Jul 2015:
Severe Droughts Affect Forests
And CO2 Storage for Years, Study Shows
Severe drought can affect a forest's growth for up to four years, a period during which it is less effective at removing carbon
A stressed forest in the southwestern United States
from the atmosphere, a new study
reports in the journal Science
. Standard climate models have assumed that forests and other vegetation bounce back quickly from extreme drought, but that assumption is far off the mark, the researchers say. Looking at data from more than 1,300 forest sites dating back to 1948, they found that living trees took an average of two to four years to recover and resume normal growth rates after droughts ended. Frequent droughts in places like the western U.S. could significantly impact the ability of forests to sequester carbon, the study found. Researchers aren't sure how drought causes these long-lasting changes, but they say there are likely three causes: Loss of carbohydrate and foliage reserves may impair growth; pests and diseases may accumulate in drought-stressed trees; and lasting damage to vascular tissues impairs water transport.
With Camera Drones, New Tool
For Viewing and Saving Nature
In a career spanning four decades, award-winning filmmaker Thomas Lennon has tackled topics as diverse as the Irish in America and a polluting chemical plant in China
. But it was his current project — a short film about the Delaware River — that opened his eyes to what he sees as a revolutionary new tool for viewing the natural world: the camera drone. In an interview with Yale Environment 360
, Lennon — who produced a video of drone images from the Delaware
— describes how drones are a major innovation that allows filmmakers to capture images from vantage points never before possible. “There’s an opportunity for visual excitement, but combined — and this is the key — with intimacy,” Lennon says. “And I think that can become a tool for artists as well as for environmentalists.”
Watch video | Read interview
17 Jul 2015:
2014 Set Multiple Global
Climate Records, NOAA Analysis Concludes
Several climate measures indicate that 2014 was the warmest year on record, according to a new report
compiled by the
National Oceanic and Atmospheric Administration (NOAA). Based on data collected from 413 scientists and 58 countries, the analysis found that sea surface temperatures, upper ocean heat content, and global sea level all achieved record levels in 2014. Four independent global data sets also indicated that 2014 global surface temperatures were the warmest on record. Earlier this year, NASA and NOAA released a similar study
stating that 2014 was the warmest year on record based on 135 years of weather reports, and President Obama cited that finding in his 2015 State of the Union address. The new analysis confirms and extends these findings to multiple indicators of global climate change.
15 Jul 2015:
'Buckyballs' May Be Able to
Capture Carbon Dioxide, Research Finds
Researchers have made progress toward using buckyballs — tiny, spherical chemical structures composed of 60 carbon molecules — to
Buckyball crystal structure
pull carbon from the atmosphere, a team from Rice University reports
in the journal Energy and Fuels
. They had previously found that buckyballs, also known as fullerene or carbon-60 molecules, have the ability to capture CO2 from high-temperature sources such as industrial flue gases and natural gas wells when combined with a polymer known as polyethyleneimine (PEI). In the new study, the researchers found that they could modify the PEI-enhanced buckyballs to capture carbon in lower-temperature environments. The advance may open the door to fine-tuning the enhanced buckyballs for a variety of carbon capture projects, the researchers say.
10 Jul 2015:
Deeper Ocean Waters Have
Absorbed Much of Excess Atmospheric Heat
The waters of the Western Pacific and Indian Ocean warmed significantly from 2003 to 2012, but most of the heat is being
Warming trends at depth in the Western Pacific
stored at depth rather than near the surface, NASA researchers explained
this week in the journal Science
. The findings shed light on mechanisms behind
the so-called global warming "hiatus," in which air temperatures appeared to rise more slowly from 2003 to 2012. Warming in the Western Pacific and Indian Ocean during that period started to appear at roughly 32 feet below the surface, the researchers say, and most of the heat was retained at depths of 300 to 1,000 feet. Their findings are based on two decades of ocean temperature records. “Overall, the ocean is still absorbing extra heat,” said Josh Willis, an oceanographer who coauthored the study. “But the top couple of layers of the ocean exchange heat easily and can keep it away from the surface for ten years or so. ... In the long run, the planet is still warming.”
09 Jul 2015:
Bird Fatalities at Wind Facilities
Can Be Prevented With New Model, Study Says
The U.S. Geological Survey has developed a new model that it says can help predict and prevent bird fatalities at wind facilities before
they are even built. The model
takes into account three parameters, all of which can be measured before construction: the total footprint of the turbines, avian traffic near the facility, and collision probability. The model used golden eagles as a case study because their soaring and hunting behaviors make them susceptible to turbine collisions. Golden eagles also are long-lived and reproduce relatively late in life, which means wind farm fatalities could have particularly severe population impacts. For two years, the model successfully estimated eagle collisions at a newly constructed wind facility in Wyoming, the researchers say. The model's simplicity "allows wind facility developers to consider ways to reduce bird fatalities without having to collect a complicated set of data," said Leslie New, a researcher at Washington State University, who led the project.
Interview: How to Get People
To Care About Climate Change
Per Espen Stoknes, a Norwegian psychologist and economist, has been doing a lot of thinking about a question that has
Per Espen Stoknes
bedeviled climate scientists for years: Why have humans failed to deal with the looming threat posed by climate change? That question is the focus of his recent book, What We Think About When We Try Not To Think About Global Warming
, in which he analyzes what he calls the psychological barriers that have made it difficult to deal realistically with the climate crisis. In an interview with Yale Environment 360
, Stoknes talks about these barriers and about how the discussion of climate change needs to be reframed. “We need a new kind of stories,” he says, “stories that tell us that nature is resilient and can rebound and get back to a healthier state, if we give it a chance to do so.”
Read the interview.
07 Jul 2015:
Self-Driving Taxis Could Spur
Major Cuts in Carbon Emissions, Study Says
By 2030, self-driving electric taxis could cut greenhouse gas emissions from car travel in the U.S. by up to 94 percent, if they were
Prototype of a small, self-driving electric taxi
to replace conventional personal vehicles, according to
an analysis published in the journal Nature Climate Change
. Autonomous taxis are projected to cut carbon emissions primarily through a process known as "right-sizing," or deploying a car that is specifically tailored to match occupancy needs of each particular trip. Right-sizing is cost-effective for both the fleet owner and for passengers, the researchers say, and companies and research groups are currently exploring how to efficiently manufacture small one- and two-seat vehicles. Optimal routing, smoother acceleration and braking, and a cleaner electric grid in 2030 would also contribute to lower carbon emissions. Autonomous taxis are projected to reduce emissions by 63 to 82 percent compared to hybrid cars likely to be on the road in 2030, and by 94 percent over a 2014 gasoline-powered model, the study found.
29 Jun 2015:
Rain Harvesting Could Provide
Major Economic Benefit in India, Study Finds
Collecting precipitation in rain barrels could result in significant savings for many people in India, according to
an analysis of
precipitation data collected by a NASA satellite. Estimates showed that harvested rain could provide at least 20 percent of average indoor water demand, or entirely irrigate a household vegetable garden. The savings associated with a vegetable garden could be between 2,500 and 4,500 rupees per year (39 to 71 U.S. dollars) — an amount equivalent to half a year’s rent in an average 1-bedroom apartment in an Indian city. In a country where the distribution of potable water is a challenge, rainwater is an untapped resource that could provide significant benefits, the researchers write in the Urban Water Journal
Photo Gallery: Scenes From
The Golden Age of Animal Tracking
Scientists are following the lives of animals in more detail than ever before, thanks to a new generation of tracking and tagging devices. From beluga whales that collect data on the Arctic Ocean to ducks that help track the spread of avian flu, data gathered by and about animals is being used to identify conservation hotspots, reduce human-animal conflicts, and monitor the health of the planet. In an e360
gallery, we look at some intriguing projects that have used state-of-the-art animal tracking and monitoring technology.
View the gallery.
24 Jun 2015:
Global Fine Particle Pollution
On the Rise Despite Regional Improvements
Air pollution from fine particulate matter has decreased significantly in North America and western Europe over the
Fine particulate air pollution levels, 2010-2012
past two decades, but increases in East and South Asia have more than made up for those improvements, as these maps based on NASA satellite data
show. The U.S. and Europe have many PM 2.5 ground-based monitoring stations, but large swaths of Africa, Asia, Central America, and South America are unmonitored. To fill these gaps, researchers have been developing techniques that use satellite data to better estimate PM 2.5 levels around the globe. They've found that, as a whole, the worsening PM 2.5 pollution in Asia outweighed improvements in North America and Europe, and global PM 2.5 concentrations have increased by 2.1 percent per year since 1998.
22 Jun 2015:
Researchers Look to Design of
Owl Wings to Make Quieter Wind Turbines
A new type of coating for wind turbines inspired by the shape of owl wings may dramatically cut noise associated with onshore
Australian masked owl in flight
wind farms, according to
research from the University of Cambridge. The scientists found that an owl's flight feathers have a microscopic down-like covering and numerous other intricate design details that smooth the passage of air over the wing, scattering sound as the owl flies. To replicate the structure, the researchers looked at designing a covering that would scatter the sound generated by a turbine blade in the same way. Early tests of their prototype material, a 3D-printed plastic coating, demonstrated that it could significantly quiet wind turbines without any appreciable impact on aerodynamics. Since wind turbines are heavily braked in order to minimize noise, the new technology could mean that turbines could spin at much higher speeds, producing more energy while making less noise.
19 Jun 2015:
Jet Contrails Can Affect
Air Temperature in Some Areas, Study Shows
Jet contrails can mimic the weather impact of clouds and significantly affect daytime and nighttime air temperature
Persistent jet contrails
swings — by up to 6 degrees Fahrenheit in some locales — researchers from Penn State have shown
. Data from the three days following September 11, 2001, when air travel was highly restricted, had shown that jet contrails — thin clouds composed of ice crystals condensed from an aircraft's exhaust — likely had an effect on air temperatures. To study the issue over a longer time period, the researchers looked at daily temperature data from locations in the South and Midwest that often see persistent jet contrails. They found that contrails, like clouds, depress the difference between daytime and nighttime temperatures, typically lowering daytime highs and raising nighttime lows. In the South, this amounted to a 6 degree F reduction in daily temperature range, and in the Midwest, roughly a 5 degree F reduction.
17 Jun 2015:
Harnessing Evaporation Could
Yield More Power than Wind, Study Shows
Using the energy produced by evaporating water, researchers at Columbia University have shown
that they can
A miniature car driven by evaporation.
power a small toy car and a flashing light — the first step, they say, in harnessing an immense energy source that could rival power production from wind and waves. The devices they built use bacterial spores that can absorb humidity and, in doing so, expand and contract with enough force to push and pull pistons and drive a rotary engine. The spores pack more energy, pound for pound, than other materials used in engineering for moving objects, said researcher Ozgur Sahin, who co-authored the study published in Nature Communication
. When evaporation energy is scaled up, he says, it could one day produce electricity from giant floating power generators that sit on bays or reservoirs or rotating machines like wind turbines that sit above water.
Interview: Is Cloning Mammoths
Science Fiction or Conservation?
Biologist Beth Shapiro has published a new book, How to Clone a Mammoth
, that looks at the many
questions — both technical and ethical — surrounding any attempt to revive extinct species. In a Yale Environment 360
interview, Shapiro, associate director of the Paleogenomics Institute at the University of California at Santa Cruz, explains why she believes new gene-editing technology could benefit critical ecosystems and living species that are now endangered. “We are in the midst of an extinction crisis,” she says. “Why would we not use whatever technologies are available to us, assuming we can go about doing it in a reasonable and ethical way?”
Read the interview.
16 Jun 2015:
Human Data Can Improve
Ecosystem Service Models, Study Says
Protected forests in Brazil, Costa Rica, Indonesia, and Thailand have prevented the release of more than 1 billion tons
Aerial view of the Amazon rainforest in Brazil.
of carbon dioxide into the atmosphere, an ecosystem service worth at least $5 billion, Georgia State University economists found
. Their conclusion about the monetary benefit of those forest protections is based on a new method they derived for valuing services such as carbon capture, conservation, and improvements in air and water quality. Instead of relying on modeling alone, the new method uses interviews and on-the-ground data to see how conservation programs affect human behavior and impact ecosystems. By combining the two types of information — environmental models and social science data — public officials can gain more realistic insights into how a particular policy might affect the environment and the people who interact with it, the researchers write in the Proceedings of the National Academy of Sciences
15 Jun 2015:
Biodiversity Limits Parasites
In Humans, Wildlife, and Plants, Study Says
High biodiversity generally limits outbreaks of disease among humans and wildlife, University of South Florida researchers write in the Proceedings of the National Academy of Sciences
. The new research is the first to quantitatively support the controversial "dilution effect hypothesis," which warns that human-driven biodiversity losses can exacerbate parasite outbreaks. Much of the debate surrounding this idea concerns whether it applies generally or only to a few select parasites. After reviewing more than 200 published scientific assessments, the USF team found "overwhelming" evidence that the dilution effect applies broadly to many parasitic species in humans and wildlife. They also found that plant biodiversity reduces the abundance of herbivore pests. The results have implications for public health efforts, the researchers say, and make a case for better management of forests, croplands, and other ecosystems.
10 Jun 2015:
Jet Fuel from Sugarcane
Cuts Aviation Carbon Emissions, Study Says
Converting sugarcane to jet fuel can reduce greenhouse gas emissions from air travel by up to 80 percent and the process could be scaled up to produce commercially viable amounts
of fuel, say researchers from the University of California, Berkeley. The new technique they developed, which is described in the Proceedings of the National Academy of Sciences
, relies on complex chemical reactions involving sugars and waste biomass from sugarcane. That crop, unlike the sugar beet, can be grown on marginal lands so it does not displace food production — a major concern that has tempered enthusiasm for biofuels in general. Jet fuel, which is responsible for roughly 2 percent of all carbon emissions, has been difficult to synthesize from biomass because of its stringent quality requirements. Biofuels were approved for commercial aviation as recently as 2011, and researchers have been seeking a viable production method for nearly a decade.
08 Jun 2015:
Reforming Mobile Phone Industry
Helps Profits and Environment, Study Says
Mobile phone manufacturers and the environment would both benefit from producing less-complex phones that
Millions of unused phones are discarded each year.
use "the cloud" — a network of remote servers connected to the Internet — to carry out power-intensive tasks, researchers say
. The current business model encourages consumers to upgrade devices frequently with little incentive to recycle them, researchers write in the International Journal of Life Cycle Assessment
. There are roughly 85 million unused phones in the U.K. alone, the researchers note, and replacing the gold they contain — not to mention copper, silver, and other rare metals
— would cost nearly $170 million and release an equivalent of 84,000 tons of CO2. Moving to a "cloud-based" system where heavy computing is done on remote servers would allow manufacturers to produce less-complex phones that are designed to last longer and require fewer valuable metals, the analysis found.
02 Jun 2015:
Pollution From Carbon Monoxide
Has Fallen Steadily Since 2000, Data Show
As these NASA satellite maps show
, carbon monoxide levels have decreased appreciably in much of the world since 2000, thanks to
Global carbon monoxide levels as of 2014
improved pollution controls on vehicles and factories and fewer forest fires. Carbon monoxide, which is produced whenever carbon-based fuels are burned, contributes to the formation of ozone, a pollutant that can have adverse health effects. A NASA satellite carrying a sensor called MOPITT — Measurements of Pollution in the Troposphere — measures carbon monoxide levels. Higher concentrations of CO are depicted on the map in orange and red and lower concentrations in yellow. NASA said that the decrease in CO levels from 2000 to 2014 was particularly noticeable in the northern hemisphere thanks to technological and regulatory innovations that have led to lower pollution levels from vehicles and industry. Carbon monoxide levels also have decreased in the southern hemisphere since 2000, due largely to a reduction in deforestation fires.
29 May 2015:
Ozone Benefits of Montreal
Protocol Already Widespread, Study Says
The planet's protective ozone layer is in far better shape today thanks to the United Nations' Montreal Protocol, which came
Ozone hole without the Montreal Protocol
into force in 1987 and restricted the use of ozone-depleting substances such as CFCs, according to a new study in Nature Communications
. The researchers used 3D atmospheric chemistry modeling to look at what might have happened to the ozone layer had the treaty not been implemented. The findings suggest that the Antarctic ozone hole would have grown by an additional 40 percent by 2013 and, had ozone-depleting substances continued to increase, the ozone layer would have become significantly thinner over other parts of the globe. A very large ozone hole over the Arctic would have occurred during the exceptionally cold Arctic winter of 2010-2011 — colder temperatures cause more loss — and smaller Arctic ozone holes would have become a regular occurrence.
Designed for the Future:
Practical Ideas for Sustainability
From packing materials made of mushrooms to buildings engineered to cool and power themselves, sustainable design can play a key role in helping people adapt to a changing planet. That’s a central message of the new book Designed for the Future
, in which more than 80 experts in sustainable design — architects, journalists, urban planners, and others — are asked to point to a specific project that gives them hope that a sustainable future is possible. Their selections vary widely, from communities that leave no carbon footprint to cutting-edge technological research programs. An e360
gallery highlights a few of the projects they say have inspired them.
View the gallery.
22 May 2015:
Many Trees in Southeast U.S.
Closely Related to Tree Species in Asia
DNA studies show that more than half the trees and shrubs in southern Appalachia can trace their ancestry to eastern Asia.
A flowering dogwood tree
Based on molecular studies of more than 250 species of trees and shrubs from Georgia to Virginia, researchers at Duke University found close ties between East Asian species, such as dogwoods, and species in the southeastern U.S. Forests throughout the northern hemisphere were joined together by the supercontinent Laurasia as recently as 180 million years ago. Then, as the great northern land mass broke into continents, eras of glaciation wiped out various tree species. Forest remnants hung on in China, Japan, small parts of Europe, and Appalachia, which explains the similarity in tree species. The research was published in the American Journal of Botany.
14 May 2015:
Biologically Inspired Coating
Will Improve Solar Panels, Researchers Say
Key characteristics of moths’ eyes, which are anti-reflective, and lotus leaves, which are water-repellant, inspired a new type of glass coating that could significantly improve the efficiency of solar panels, say researchers at Oak Ridge National Laboratory
. The extremely durable coating can be customized to be fog-resistant, anti-reflective, and superhydrophobic — meaning it repels water drops so efficiently that they barely make contact with the solar panel surface, literally bouncing off and carrying away dirt and dust that hamper performance. The key component is a nanostructured layer of glass film that, under a microscope, has a porous texture resembling coral, which helps the solar cells absorb more light, the researchers say. Reflecting less sunlight means a 3 to 6 percent increase in light-to-electricity conversion efficiency and power output, studies show. The coating can be fabricated using standard industry techniques, the researchers say, making it easy and inexpensive to scale up and incorporate in current products.
06 May 2015:
Backyard Bird Feeders May Put
Native Species at a Disadvantage, Study Says
Backyard bird feeders tend to attract aggressive, introduced bird species while discouraging native species that eat
A sparrow eats at a backyard bird feeder.
insects and nectar, essentially restructuring urban bird communities and skewing them toward non-native species, a new study
says. Data based on nearly 600 surveys of 18,000 birds from 33 species in New Zealand show that yards with bird feeders tended to attract non-native omnivores such as house sparrows, spotted doves, and blackbirds. Outdoor areas without bird feeders had significantly more native bird species such as the grey warbler, whose diet consists mainly of insects. Although the population trends reversed when feeders were removed, the researchers say that over time bird feeders in urban areas likely give non-native bird species a competitive and reproductive edge over native species.
05 May 2015:
Pollen May Play Surprising
Role in Climate and Cloud Formation
Grains of pollen may be seeding clouds and affecting the planet's climate in unexpected ways, University of Michigan researchers
Grains of pollen can break into even smaller particles.
write in the journal Geophysical Research Letters
. Scientists had assumed that pollen particles were too large to remain in the atmosphere long enough to interact with the sun's radiation or trigger cloud formation. The study found, however, that pollen grains are capable of disintegrating into much smaller particles and that exposure to humidity can accelerate pollen's breakdown. Using a cloud-making laboratory chamber, the researchers showed that six common types of pollen — ragweed and oak, pecan, birch, cedar, and pine trees — could break into particles small enough to draw moisture and form clouds. "What happens in clouds is one of the big uncertainties in climate models right now," author Allison Steiner said.
30 Apr 2015:
Volcanic Eruption in Chile Could
Have an Effect on Climate, NASA Data Show
Calbuco volcano, which erupted in southern Chile last week for the first time since 1972, has been injecting climate-changing
Sulfur dioxide from Calbuco volcano
gases directly into an upper layer of the atmosphere, NASA satellite data
show. The particularly explosive eruption shot sulfur dioxide, an acrid-smelling gas that can cause respiratory problems at ground level, up into the stratosphere, where it reacts with water vapor to create sulfate aerosols that reflect sunlight and can sometimes have a slight cooling effect. So far, Calbuco has released an estimated 0.3 to 0.4 million tons of sulfur dioxide (SO2) as high as 13 miles, where it will last much longer and travel much farther than if released closer to the earth's surface. The SO2 will gradually convert to sulfate aerosol particles, but it is not clear yet whether there will be a cooling effect associated with Calbuco's eruption, researchers say.
24 Apr 2015:
Long-Term CO2 Record by Keeling
Named National Historic Chemical Landmark
The Keeling Curve — a long-term record of rising carbon dioxide in the planet’s atmosphere — will be named a National Historic
Chemical Landmark, the American Chemical Society announced
yesterday. The late geochemist Charles David Keeling began collecting precise, systematic data on atmospheric CO2 concentrations at Hawaii's Mauna Loa Observatory in 1958. Since then, the rigorous and continuous measurements have become the most widely recognized record of humans' impact on the planet, helping to illustrate the link between rising CO2 levels from burning fossil fuels and global warming. Other works highlighted by National Historic Chemical Landmark program include the discovery of penicillin, deciphering of the genetic code, and the works of Rachel Carson, Thomas Edison, and George Washington Carver.