Global study of seed consumption uncovers wider risk to plant species

Deborah Smith in the University of New South Wales Newsroom: The first worldwide study of animals and the seeds they eat has overturned a long-held assumption – that large animals mainly eat large seeds. The finding by UNSW Australia scientists has implications for conservation showing that a wider variety of plants than is often thought could be at risk if large animals go extinct and do not disperse their seeds.

In a comprehensive study, UNSW’s Si-Chong Chen and Professor Angela Moles compiled and analysed data on more than 13,000 animal-seed interactions, based on previously published reports. “It is the first broad-scale study of the relationship between animal body mass and ingested seed size ever undertaken,” says Ms Chen, a PhD candidate in the UNSW School of Biological, Earth and Environmental Sciences.

“We covered all vertebrate groups – fish, amphibians, reptiles, birds and mammals. And we included animals from many different areas – from the Arctic tundra to the tropical rainforests.”...The smallest seeds in the study were the tiny seeds of the mountain snowberry, and they were eaten by the smallest animals in the study – skinks on the Chatham Islands near New Zealand. The largest seeds were the 9-centimetre long seeds of the African tropical forest tree, Balanites wilsonia. They were eaten by the largest animals in the study – 4-tonne African elephants.

“It has long been predicted that as the body size of animals increases so does the size of the seeds they ingest,” says Ms Chen. “Big animals do eat some big seeds from fleshy fruits. But the prediction is wrong because it overlooks the fact that big animals like buffalos, cows, deer and zebras also accidentally vacuum up hundreds of small seeds as they graze on short grassy vegetation.”...

Sunflower with bee, shot by Rasbak, Wikimedia Commons, under the Creative Commons Attribution- Share Alike 3.0 Unported license 

Ethiopian dam deal ignores science, warn experts

Rehab Abd Almohsen in SciDev.net: Water scientists from Egypt have raised concerns over a declaration governing the Grand Ethiopian Renaissance Dam that is meant to ensure fair access to Nile water for countries downstream.

The Declaration of principles, which the leaders of Egypt, Ethiopia and Sudan signed in Khartoum, Sudan, on 23 March, is meant to regulate Nile water use following political upheaval over the dam, which is about a third into its construction.

Talking to SciDev.Net, scientists monitoring the declaration’s creation have warned that concerns over the dam’s impact on the environment and local people have been sidelined for gains in political negotiations.

Nader Noureddine, a water resources and soil researcher at Cairo University, says the technical committee appointed by all three countries to oversee the dam’s construction will be allowed to study documents provided by the Ethiopian government, but “will not be allowed to visit the dam or to witness the work on the site”. This, Noureddine says, will seriously impact its ability to make an evidence-based assessment of the dam’s environmental impacts.

“They are not even allowed to discuss issues like the width of the reservoir and specifications of the dam,” Noureddine says. A report from the committee is due to be issued in around 15 months.

Meanwhile, Dia El-Din Ahmed El-Quosy, a professor at Egypt’s National Water Research Center and former advisor to the country’s Ministry of Water Resources and Irrigation, says: “The agreement is free of any technical details, such as how the dam reservoir will be filled.”...

NASA image of the Aswan Dam in Egypt

More food, low pollution effort gains traction

A press release from the University of Maryland Center for Environmental Science: Nitrogen fertilizers make it possible to feed more people in the world than ever before. However, too much of it can also harm the environment. Professor Eric Davidson, director of the UMCES Appalachian Laboratory, has been leading a group of scientists, economists, social scientists, and agriculture experts in figuring out how to produce more food while lowering pollution at the same time. He calls it a “Mo Fo Lo Po”: more food, low pollution.

“The main objective is to produce abundant, nutritious, and affordable food and give farmers a chance to make a living, but do all of this while minimizing pollution of the environment,” said Davidson, whose research career has focused on how human changes to the land affect carbon and nitrogen in soil, water, and air.

Averaged globally, about half of the fertilizer nitrogen applied to farms is typically removed with the crops, while the other half either remains in the soil or is lost from the farmers’ fields. Knowledge and techniques already exist to make agriculture more productive and environmentally sustainable at the same time, yet many economic and social barriers still stand in the way of widespread adoption of practices by farmers.

...“Our objective is to bring together communities of scientists and stakeholders who would otherwise be unlikely to get together to talk about nitrogen issues as it relates to food security, pollution, human health impacts, global warming, ozone destruction, and the list goes on,” he said.

Less than two years later, the group has produced a collection of papers in Journal of Environmental Quality, published this month. A special section on Nitrogen Use Efficiency, guest edited by Davidson, provides a closer look at the economic, social, and technical impediments to improving efficiency of nitrogen use in crop and animal farms....

Photo of wheat stalks by CSIRO, Wikimedia Commons, under the Creative Commons Attribution 3.0 Unported license

Ignored by government, Canadian academics offer their own climate policy

Lesley Evans Ogden in Science: Under the conservative government of Prime Minister Stephen Harper, Canada has become a tough and frustrating political environment for researchers trying to advance evidence-based policies to reduce emissions. The country has withdrawn from international climate pacts, muzzled government climate researchers, and put new regulatory efforts on the back burner. Now, one group of prominent Canadian academics is trying to change the dynamic by releasing its own set of climate policy recommendations for the nation.

“We believe that putting options on the table is long overdue in Canada,” write the 71 authors of the Sustainable Canada Dialogues report, released today. The authors, whose expertise ranges broadly across scientific, sociological, and political disciplines, were organized by Catherine Potvin, a climate and policy researcher at McGill University in Montreal. One goal, she says, is to encourage Canadians—and ultimately their government—to support “ambitious and thoughtful commitments to emission reductions” at a global negotiating conference set for Paris in December. The group is trying “to do whatever can be done to raise the level of ambition of Canada prior to the Paris conference,” Potvin tells ScienceInsider.

“Climate change is the most serious ‘symptom’ of non-sustainable development,” concludes the report, which offers a detailed policyroad map for Canada to achieve 100% reliance on low-carbon electricity by 2035. It calls for Canada to reduce greenhouse emissions by 26% to 28% below 2005 levels by 2025 and eliminate at least 80% of emissions by midcentury. Ten major recommendations include calls to impose a price on carbon emissions through a tax or pollution permit trading system, add more solar and wind power to Canada’s bountiful hydropower supplies, and eliminate subsidies for fossil fuels....

This is a picture of Syncrude's base mine in Athabasca. The yellow structures are the bases of pyramids made of sulphur - it is not economical for Syncrude to sell the sulphur so it stockpiles it instead. Behind that is the tailings pond, held in by what is recognized as the largest dam in the world. The extraction plant is just to the right of this photograph and most of the mine is to the left. Shot by Tasty Cakes, public domain

The green lungs of our planet are changing

A press release from Goethe University (Frankfurt, Germany): Are leaves and buds developing earlier in the spring? And do leaves stay on the trees longer in autumn? Do steppe ecosystems remaining green longer and are the savannas becoming drier and drier?  In fact, over recent decades, the growing seasons have changed everywhere around the world. This was determined by a doctoral candidate at the Goethe University as part of an international collaboration based on satellite data. The results are expected to have consequences for agriculture, interactions between species, the functioning of ecosystems, and the exchange of carbon dioxide and energy between the land surface and the atmosphere.

"There is almost no part of the Earth that is not affected by these changes", explains Robert Buitenwerf, doctoral candidate at the Institute for Ph
ysical Geography at the Goethe University. He has evaluated satellite data from 1981 to 2012 with regard to 21 parameters on vegetation activity, in order to determine the point in time, the duration, and the intensity of growth from the northernmost conifer forests to tropical rain forests. His conclusion: On 54 percent of the land surface, at least one parameter of vegetation activity has moved away from the mean value by more than two standard deviations.

As reported by researchers from Frankfurt, Freiburg and New Zealand in the current edition of the professional journal "Nature Climate Change", leaves are now sprouting earlier in most of the climate zones of the far north. Although they are also dropped somewhat earlier in autumn, the overall vegetation period has grown longer. On the other hand, in our latitudes, trees and shrubs are losing their leaves later than they have up to now.

To date, not much research has been conducted on the regions of the southern hemisphere.  In those areas, the researchers found that in several savannas of South America, southern Africa and Australia, the vegetation activity has decreased during dry seasons. "Although these savannas have similar vegetation and comparable climates, the changes in vegetation activity differ. That may be attributable to the differences in the functioning of the respective ecosystems", says Buitenwerf.

In this respect, the seasonal distribution of leaf growth constitutes a sensitive indicator: it indicates how various ecosystems react to changes in the environment. "Although vegetation changes in the northern hemisphere have conclusively been attributed to climate change by other studies, attributing all the changes found in our study would require a more complex analysis," Buitenwerf emphasizes. In the northern hemisphere it has already been shown that species whose life cycles depend on the vegetation period are endangered by these severe changes.  Consequences for species in the southern hemisphere are as yet unclear....

Redwoods in Muir Woods, shot by Meburian, Wikimedia Commons,  under the Creative Commons Attribution-Share Alike 3.0 Unported license 

Munching bugs thwart eager trees, reducing the carbon sink

University of Wisconsin-Madison News: In a high carbon dioxide world, the trees would come out ahead. Except for the munching bugs. A new study published today [Monday, March 2, 2015] in Nature Plants shows that hungry, plant-eating insects may limit the ability of forests to take up elevated levels of carbon dioxide in the atmosphere, reducing their capacity to slow human-driven climate change.

The finding is significant because climate change models typically fail to consider changes in the activities of insects in the ecosystem, says Richard Lindroth, a professor of ecology at the University of Wisconsin-Madison and the leader of the study. The research suggests it’s time to add insects to the models.

Carbon dioxide typically makes plants grow faster and makes them more efficient in how they use nutrients. But the amount of damage caused by leaf-munching bugs in the study nearly doubled under high carbon dioxide conditions, leading to an estimated 70g of carbon-sequestering biomass lost per meter squared per year.

“This is the first time, at this scale, that insects have been shown to compromise the ability of forests to take up carbon dioxide,” Lindroth says.

In addition, as feeding increased, more nutrients moved from the canopy to the forest floor in the form of insect fecal material and chewed-on leaf scraps, mixing into the soil and likely altering the nutrient profile of the forest....

Photo of a tent caterpillar by Mary A. Jamieson/UW-Madison Department of Entomology

Isolated wetlands have significant impact on water quality

A press release from Indiana University: Geographically isolated wetlands play an outsized role in providing clean water and other environmental benefits even though they may lack the regulatory protections of other wetlands, according to an article by Indiana University researchers and colleagues.

Given those benefits, the authors argue, decision-makers should assume that isolated wetlands are critical for protecting aquatic systems, and the burden of proof should be on those who argue on a case-by-case basis that individual wetlands need not be protected.

“Geographically isolated wetlands provide important benefits such as sediment and carbon retention, nutrient transformation and water-quality improvement, all of which are critical for maintaining water quality,” said lead author John M. Marton, assistant scientis
t at the IU Bloomington School of Public and Environmental Affairs. “We demonstrate that continued loss of these wetlands would likely cause serious harm to North American waters.”

The article, “Geographically Isolated Wetlands Are Important Biogeochemical Reactors on the Landscape,” will appear in BioScience, the journal of the American Institute of Biological Sciences, and is available online. Co-authors include Christopher B. Craft, the Janet Duey Professor in Rural Land Development with SPEA at IU Bloomington, along with researchers from the U.S. Environmental Protection Agency, the University of Western Ontario, the University of Waterloo, the University of Florida and the University of South Florida.

Geographically isolated wetlands are formed by natural forces that create depressions in the landscape, resulting in conditions suitable for wetland plants and soils. They include the prairie potholes of the upper Midwest, the playas of the Southwest, vernal pools in New England and California, and the Carolina Bays.

Citing research literature, the authors say geographically isolated wetlands are highly effective “biogeochemical reactors” that improve water quality. They often retain water longer than protected waters, such as streams and wetlands that are directly connected to navigable water. And they have a higher ratio of perimeter to area, allowing more opportunities for reactions to take place....

A vernal pool in the Totts Gap Preserve in Pennsylvania, shot by Nicholas A. Tonelli Nicholas A. Tonelli, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license 

Capturing and storing carbon in soil: Is it real and can it scale?

EurekAlert via Arizona State University: Can beef production help restore ecosystems? A team of scientists, advisors and communications specialists are banding together to explore whether ranching management can create robust soils, watersheds and wildlife habitat while sequestering atmospheric carbon dioxide.

The Arizona State University-SoilCarbon Nation team is examining the adaptive multi-paddock (AMP) grazing management technique that involves using small-sized fields to provide short periods of grazing for livestock and long recovery periods for fields. The method mimics the migrations of wild herd animals, such as elk, bison and deer. The science team proposes a whole system science measurement approach in comparing AMP grazing with conventional, continuous grazing methods.

Peter Byck, professor of practice at the School of Sustainability and the Walter Cronkite School of Journalism and Mass Communication at ASU, is helping organize the project. "By using measures - such as the carbon stored, the water absorbed and retained, populations of fungi, bacteria, wild life and insects, and rancher and animal well-being - we are comparing adaptive grazing with conventional grazing to see if the former actually improves ranch ecosystems," he said. "We hope to study and compare 36 ranches located in four diverse eco-regions across the U.S. and southern Canada."

While individual members of the team concentrate on aspects and impacts of various grazing techniques, Byck's focus is to discover whether the methods store carbon in the soil, and if so, which is the most successful.

According to Byck, the idea for the project came from researching Soil Carbon Cowboys, a short Carbon Nation 2.0 film made in collaboration with ASU. His feature documentary, 2011's Carbon Nation, focuses on climate change solutions....

"While filming Soil Carbon Cowboys, we came across ranchers who were adopting healthier grazing practices to rejuvenate their land and their livestock," said Byck. "What they did not know is that they were helping capture a significant amount of carbon dioxide from the air."....

US Agricultural Research Service photo of a cattle herd

Strong storms to become stronger, weak storms to become weaker

A press release at the University of Toronto News: A study led by atmospheric physicists at the University of Toronto finds that global warming will not lead to an overall increasingly stormy atmosphere, a topic debated by scientists for decades. Instead, strong storms will become stronger while weak storms become weaker, and the cumulative result of the number of storms will remain unchanged.

“We know that with global warming we’ll get more evaporation of the oceans,” said Frédéric Laliberté, a research associate at U of T’s physics department and lead author of a study published this week in Science. “But circulation in the atmosphere is like a heat engine that requires fuel to do work, just like any combustion engine or a convection engine.”

The atmosphere’s work as a heat engine occurs when an air mass near the surface takes up water through evaporation as it is warmed by the sun and moves closer to the equator. The warmer the air mass is, the more water it takes up. As it reaches the equator, it begins to ascend through the atmosphere, eventually cooling as it radiates heat out into space. Cool air can hold less moisture than warm air, so as the air cools, condensation occurs, which releases heat.  When enough heat is released, air begins to rise even further, pulling more air behind it producing a thunderstorm. The ultimate “output” of this atmospheric engine is the amount of heat and moisture that is redistributed between the equator and the North and South Poles.

“By viewing the atmospheric circulation as a heat engine, we were able to rely on the laws of thermodynamics to analyze how the circulation would change in a simulation of global warming,” said Laliberté. “We used these laws to quantify how the increase in water vapour that would result from global warming would influence the strength of the atmospheric circulation.”

...The scientists concluded that the increase in water vapour was making the process less efficient by evaporating water into air that is not already saturated with water vapour. They showed that this inefficiency limited the strengthening of atmospheric circulation, though not in a uniform manner. Air masses that are able to reach the top of the atmosphere are strengthened, while those that cannot are weakened...

A thunderstorm over Ueterson, Germany, shot by Huhu Uet, Wikimedia Commons,  under the Creative Commons Attribution-Share Alike 3.0 Unported license 

Wiggles: Inconsistencies undermine model reliability for projecting decade-to-decade warming

Science 2.0: A new study finds that most climate models may have wiggles that undermine accuracy - but they are likely underestimating the degree of decade-to-decade variability occurring in mean surface temperatures as Earth's atmosphere warms.

The models also provide inconsistent explanations of why this variability occurs in the first place and such discrepancies undermine the models' reliability for projecting the short-term pace as well as the extent of future warming, the study's authors warn.  As such, we shouldn't over-interpret recent temperature trends, no matter what blizzard his New York City and leads to exploitation of climate science to generate media pageviews.

"The inconsistencies we found among the models are a reality check showing we may not know as much as we thought we did," said lead author Patrick T. Brown, a Ph.D. student in climatology at Duke's Nicholas School of the Environment. "This doesn't mean greenhouse gases aren't causing Earth's atmosphere to warm up in the long run. It just means the road to a warmer world may be bumpier and less predictable, with more decade-to-decade temperature wiggles than expected. If you're worried about climate change in 2100, don't over-interpret short-term trends. Don't assume that the reduced rate of global warming over the last 10 years foreshadows what the climate will be like in 50 or 100 years."

To conduct their study, they analyzed 34 climate models used by the Intergovernmental Panel on Climate Change (IPCC) in its fifth and most recent assessment report, finalized last November.  The analysis found good consistency among the 34 models explaining the causes of year-to-year temperature wiggles, Brown noted. The inconsistencies existed only in terms of the model's ability to explain decade-to-decade variability, such as why global mean surface temperatures warmed quickly during the 1980s and 1990s, but have remained relatively stable since then....

Wrong kind of model -- Fashion Week in Budapest, shot from stylemagazin.hu, Wikimedia Commons

Scientists 'must be emotionally charged' about climate change to highlight its dangers, claims expert

Tom Bawden in the Independent (UK): Climate scientists must inject more emotion and personal experience into their communications with the public to underline the dangers of global warming, according to a leading professor.

Chris Rapley, a professor of climate science at University College London, is urging colleagues to ditch “academic, fact-based approaches” to the subject in favour of “charged” narratives. He recently performed 2071, a one-man show giving a personalised account of what climate change means for him, at the Royal Court theatre in London and the Deutsches Schauspielhaus in Hamburg.

Professor Rapley was prompted to do his show amid a growing realisation that scientists were not communicating the dangers of climate change and the importance of tackling it as well as they could. “There is a growing recognition among the science community that results that are emotionally, ideologically or politically charged need to be communicated using a different approach to the traditional ‘information deficit’ method,” Professor Rapley told The Independent.

“A narrative approach in which the scientist offers  the insights based on their personal experience provides a powerful alternative. But  it is one with which academics, trained to adopt an ‘academic’, fact-based approach, and driven to satisfy professional norms of impartiality and objectivity, find themselves uncomfortable.”

He added: “Not all scientists have to engage with society as communicators or as participants in policymaking, but a sufficient numberneed to do so in order to justify society’s investment in their science,” he said....

A polar bear in Spitzbergen, shot by Jerzy Strzelecki, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

New challenges for ocean acidification research

A press release from GEOMAR, the Helmholtz Centre for Ocean Research-Kiel: To continue its striking development, ocean acidification research needs to bridge between its diverging branches towards an integrated assessment. This is the conclusion drawn by Prof. Ulf Riebesell from GEOMAR Helmholtz Centre for Ocean Research Kiel and Dr. Jean-Pierre Gattuso from the French Centre National de la Recherche Scientifique (CNRS) and Université Pierre et Marie Curie. In a commentary in the journal “Nature Climate Change”, the two internationally renowned experts reflect on the lessons learned from ocean acidification research and highlight future challenges.

Over the past decade, ocean acidification has received growing recognition not only in the scientific area. Decision-makers, stakeholders, and the general public are becoming increasingly aware of “the other carbon dioxide problem”. It is time to reflect on the successes and deficiencies of ocean acidification research and to take a look forward at the challenges the fastest growing field of marine science is facing. In the January issue of the journal “Nature Climate Change” Ulf Riebesell, professor for Biological Oceanography at GEOMAR Helmholtz Centre for Ocean Research Kiel, and Jean-Pierre Gattuso from the French Centre National de la Recherche Scientifique (CNRS) urge the international scientific community to undertake a concerted interdisciplinary effort. According to the two experts, future ocean acidification research will have to deal with three major challenges: It needs to expand from single to multiple drivers, from single species to communities and ecosystems, and from evaluating acclimation to understanding adaptation. “The growing knowledge in each of the diverging research branches needs to be assimilated into an integrated assessment”, Prof. Riebesell points out.

For the scientific community, it is obvious that ocean acidification does not occur in isolation. Rising temperatures, loss of oxygen, eutrophication, pollution and other drivers happen simultaneously and interact to influence the development of marine organisms and communities. “The effects can be additive, synergistic or antagonistic and it is generally not possible to extrapolate from single- to multiple-driver responses”, Prof. Riebesell explains. “But with an increasing number of parameters, experiments become increasingly challenging in terms of time, space and costs. Also, it becomes ever more difficult to compare and verify results of similar studies.”

There is now an impressive body of scientific literature on how individual species react to ocean acidification as a single driver. Many calcifying organisms such as corals, mussels or snails will find it more and more difficult to build their shells and skeletons. The extra energy needed for calcification will be lacking for other biological processes, such as growth or reproduction. "But an open question is to what extent results from short-term, single-driver laboratory experiments can be extrapolated to the real world“, Dr. Gattuso states.

Field experiment on the effects of ocean acidification with the KOSMOS mesocosms developed in Kiel. Photo: Maike Nicolai, GEOMAR

NASA to study how African fires affect climate

Jan Piotrowski in SciDev.net: Climate scientists have received a boost of up to US$150 million from US space agency NASA for a five year campaign to probe how air pollution, manmade fires across Africa and warming oceans may affect our climate.

The money will be split equally among five projects under the umbrella of the agency’s Earth Venture initiative, which is designed to fill major knowledge gaps in earth sciences. A mixture of plane flights and surface measurements will shed light on processes that NASA’s satellite missions cannot pick up.

The projects are: Atmospheric chemistry and air pollution, Ecosystem chan
ges in a warming ocean, Greenhouse gas sources, African fires and Atlantic clouds, and Melting Greenland glaciers....  This is NASA’s second series of Earth Venture suborbital projects, recommended by the National Research Council in 2007. In 2010, the first series of five projects was selected.

"These new investigations address a variety of key scientific questions critical to advancing our understanding of how Earth works," said Jack Kaye, associate director for research in NASA's Earth Science Division in Washington in a NASA press release. “These innovative airborne experiments will let us probe inside processes and locations in unprecedented detail that complements what we can do with our fleet of Earth-observing satellites.”

Collecting hard data is the goal, but NASA scientist Hal Maring says that it is much more than an academic exercise — all projects were selected with a “heavy bias” towards their relevance for policy. “Our mission is to push the boundaries of field science to address weaknesses in our knowledge of Earth systems,” he says. “But behind these words is the assumption that the science better make a difference.”...

NASA image of fires in the Gambia in 2002

Global warming's influence on extreme weather

A press release from Stanford University: Extreme climate and weather events such as record high temperatures, intense downpours and severe storm surges are becoming more common in many parts of the world. But because high-quality weather records go back only about 100 years, most scientists have been reluctant to say if global warming affected particular extreme events.

On Wednesday, Dec. 17, at the American Geophysical Union's Fall Meeting in San Francisco, Noah Diffenbaugh, an associate professor of environmental Earth system science at the Stanford School of Earth Sciences, will discuss approaches to this challenge in a talk titled "Quantifying the Influence of Observed Global Warming on the Probability of Unprecedented Extreme Climate Events." He will focus on weather events that – at the time they occur – are more extreme than any other event in the historical record.

Diffenbaugh emphasizes that asking precisely the right question is critical for finding the correct answer. "The media are often focused on whether global warming caused a particular event," said Diffenbaugh, who is a senior fellow at the Stanford Woods Institute for the Environment. "The more useful question for real-world decisions is: 'Is the probability of a particular event statistically different now compared with a climate without human influence?'"

Diffenbaugh said the research requires three elements: a long record of climate observations; a large collection of climate model experiments that accurately simulate the observed variations in climate; and advanced statistical techniques to analyze both the observations and the climate models.

One research challenge involves having just a few decades or a century of high-quality weather data with which to make sense of events that might occur once every 1,000 or 10,000 years in a theoretical climate without human influence.

But decision makers need to appreciate the influence of global warming on extreme climate and weather events. "If we look over the last decade in the United States, there have been more than 70 events that have each caused at least $1 billion in damage, and a number of those have been considerably more costly," said Diffenbaugh. "Understanding whether the probability of those high-impact events has changed can help us to plan for future extreme events, and to value the costs and benefits of avoiding future global warming."

Navarre Beach, Florida, after Hurricane Katrina in 2005. FEMA photo

NASA study shows 13-year record of drying Amazon caused vegetation declines

A press release from NASA:With global climate models projecting further drying over the Amazon in the future, the potential loss of vegetation and the associated loss of carbon storage may speed up global climate change.

The study was based on a new way to measure the “greenness” of plants and trees using satellites. While one NASA satellite measured up to 25 percent decline in rainfall across two thirds of the Amazon from 2000 to 2012, a set of different satellite instruments observed a 0.8 percent decline in greenness over the Amazon. The study was published on Nov. 11 in Proceedings of the National Academy of Sciences.

While the decline of green vegetation was small, the area affected was not: 2.1 million square miles (5.4 million square kilometers), equivalent to over half the area of the continental United States. The Amazon's tropical forests are one of the largest sinks for atmospheric carbon dioxide on the planet.

"In other words, if greenness declines, this is an indication that less carbon will be removed from the atmosphere. The carbon storage of the Amazon basin is huge, and losing the ability to take up as much carbon could have global implications for climate change," said lead author Thomas Hilker, remote sensing specialist at Oregon State University in Corvallis, Oregon. Plants absorb carbon dioxide as part of photosynthesis, the process by which green plants harvest sunlight. The healthier the plants, the greener the forest.

The Amazon basin stores an estimated 120 billion tons of Earth's carbon – that's about 3 times more carbon than humans release into the atmosphere each year. If vegetation becomes less green, it would absorb less of that carbon dioxide. As a result, more of human emissions would remain in the atmosphere, increasing the greenhouse effect that contributes to global warming and alters Earth's climate...

Popcorn clouds above the Amazon rainforest, August 19, 2009. This type of cloud forms during the dry season, likely from water vapor released by plants during transpiration. Image Credit: NASA's Earth Observatory

Buckyballs enhance carbon capture

A press release from Rice University: Rice University scientists have discovered an environmentally friendly carbon-capture method that could be equally adept at drawing carbon dioxide emissions from industrial flue gases and natural gas wells.

The Rice lab of chemist Andrew Barron revealed in a proof-of-concept study that amine-rich compounds are highly effective at capturing the greenhouse gas when combined with carbon-60 molecules. The research is the subject of an open-access paper today in Nature’s online journal Scientific Reports.

“We had two goals,” Barron said. “One was to make the compound 100 percent selective between carbon dioxide and methane at any pressure and temperature. The other was to reduce the high temperature needed by other amine solutions to get the carbon dioxide back out again. We’ve been successful on both counts.”

Tests from one to 50 atmospheric pressures showed the Rice compound captured a fifth of its weight in carbon dioxide but no measurable amount of methane, Barron said, and the material did not degrade over many absorption/desorption cycles.

Carbon-60, the soccer ball-shaped molecule also known as buckminsterfullerene (or the “buckyball”) was discovered at Rice by Nobel Prize laureates Richard Smalley, Robert Curl and Harold Kroto in 1985. The ultimate curvature of buckyballs may make them the best possible way to bind amine molecules that capture carbon dioxide but allow desirable methane to pass through.

The Rice lab used buckyballs as crosslinkers between amines, nitrogen-based molecules drawn from polyethyleneimine. The lab produced a brown, spongy material in which hydrophobic (water-avoiding) buckyballs forced the hydrophilic (water-seeking) amines to the outside, where passing carbon dioxide could bind to the exposed nitrogen.

When Barron and his team began combining carbons and amines several years ago, they noticed an interesting progression: Flat graphene absorbed carbon dioxide well, multiwalled nanotubes absorbed it better, and thinner single-walled nanotubes even better. “That suggested the curvature was important,” Barron said. “C-60, being a sphere, has the highest possible curvature among carbon materials.”...

Carbon-60 molecules, also known as buckyballs, were combined with amines in a compound that absorbs a fifth of its weight in carbon dioxide. It shows potential as an environmentally friendly material for capturing carbon from natural gas wells and industrial plants. (Courtesy of the Barron Research Group/Rice University)

New method for quickly determining antibiotic resistance

A press release from Uppsala University: Scientists from Uppsala University, the Science for Life Laboratory (SciLifeLab) in Stockholm and Uppsala University Hospital have developed a new method of rapidly identifying which bacteria are causing an infection and determining whether they are resistant or sensitive to antibiotics. The findings are now being published in the Journal of Clinical Microbiology.

‘Clinical use of the method would mean that the right antibiotic treatment could be started straightaway, reducing unnecessary use of antibiotics,’ says Professor Dan I. Andersson of Uppsala University, who headed the study jointly with Professor Mats Nilsson of SciLifeLab in Stockholm and Stockholm University.

Antibiotic resistance is a growing medical problem that threatens human health all
over the world. Today, many people are dying because of infections caused by resistant bacteria. When an infected person is treated with antibiotics, ‘empirical therapy’ is usually provided. This means that the choice of antibiotic is based on the resistance situation of the bacteria in a large population (such as the Swedish population), rather than on the resistance, if any, of the bacteria in the infected person’s body. The result is sometimes selection of an antibiotic drug that is ineffective against the bacteria concerned, because the latter is resistant to the drug chosen. This, in turn, boosts the use of antibiotics, especially what are known as ‘broad-spectrum’ antibiotics that work on many types of bacteria. One possible solution to these problems would be for us to have reliable methods of quickly and easily identifying the bacterial species causing the infection and its resistance pattern, and apply the correct treatment immediately.

Professor Andersson continues: ‘This is just what we’ve been working on in our study. We have developed a new method that permits identification of both the species and the resistance pattern of bacteria in urinary infections in less than four hours. By comparison, the resistance determination done at present takes one to two days.’...

Agar plate with colonies, image from NOAA

New technology may speed up, build awareness of landslide risks

A press release from Oregon State University: Engineers have created a new way to use lidar technology to identify and classify landslides on a landscape scale, which may revolutionize the understanding of landslides in the U.S. and reveal them to be far more common and hazardous than often understood.

The new, non-subjective technology, created by researchers at Oregon State University and George Mason University, can analyze and classify the landslide risk in an area of 50 or more square miles in about 30 minutes - a task that previously might have taken an expert several weeks to months. It can also identify risks common to a broad area rather than just an individual site.

And with such speed and precision, it reveals that some landslide-prone areas of the Pacific Northwest are literally covered by landslides from one time or another in history. The system is based on new ways to use light detecting and ranging, or lidar technology, that can seemingly strip away vegetation and other obstructions to show land features in their bare form.

“With lidar we can see areas that are 50-80 percent covered by landslide deposits,” said Michael Olsen, an expert in geomatics and the Eric HI and Janice Hoffman Faculty Scholar in the OSU College of Engineering. “It may turn
out that there are 10-100 times more landslides in some places than we knew of before.

“We’ve always known landslides were a problem in the Pacific Northwest,” Olsen said. “Many people are just now beginning to realize how big the problem is.”…

This massive landslide near Oso, Washington, in March, 2014, killed 43 people and was one of the most deadly in U.S. history. (Photo by Jonathan Godt, courtesy of U.S. Geological Survey)

Salinity matters when it comes to sea level changes

A press release from Lawrence Livermore National Laboratory: Using ocean observations and a large suite of climate models, Lawrence Livermore National Laboratory scientists have found that long-term salinity changes have a stronger influence on regional sea level changes than previously thought.

“By using long-term observed estimates of ocean salinity and temperature changes across the globe, and contrasting these with model simulations, we have uncovered the unexpectedly large influence of salinity changes on ocean basin-scale sea level patterns,” said LLNL oceanographer Paul Durack, lead author of a paper appearing in the November issue of the journal Environmental Research Letters (link is external).

Sea level changes are one of the most pronounced effects of climate change impacts on the Earth and are primarily driven by warming of the global ocean along with added water from melting land-based glaciers and ice sheets. In addition to these effects, changes in ocean salinity also can affect the height of the sea, by changing its density structure from the surface to the bottom of the ocean.

The team found that there was a long-term (1950-2008) pattern in halosteric (salinity-driven) sea level changes in the global ocean, with sea level increases occurring in the Pacific Ocean and sea level decreases in the Atlantic. These salinity-driven sea level changes have not been thoroughly investigated in previous long-term estimates of sea level change. When the scientists contrasted these results with models, the team found that models also simulated these basin-scale patterns, and that the magnitude of these changes was surpri
singly large, making up about 25 percent of the total sea level change.

“By contrasting two long-term estimates of sea level change to simulations provided from a large suite of climate model simulations, our results suggest that salinity has a profound effect on regional sea level change,” Durack said. “This conclusion suggests that future sea level change assessments must consider the regional impacts of salinity-driven changes; this effect is too large to continue to ignore.”...

Lined with bottles triggered at different levels of the ocean, this conductivity, temperature and depth profiler bearing a suite of sampling bottles is a mainstay of oceanography. It can be deployed to depths of 6,000 meters to study changes in ocean temperature and salinity. Photo courtesy of Ann Thresher/CSIRO

Study counters case for climate change-violence link

Lou Del Bello in SciDev.net: Climate change is far from being solely to blame for violence in Sub-Saharan Africa, say researchers — other factors matter much more. Their paper, published on 10 November in the journal Proceedings of the National Academy of Sciences, contradicts earlier studies that found that higher temperatures are a major risk factor in conflict.

For instance, last year a different group concluded that a shift towards hotter conditions by a single statistical unit known as a ‘standard deviation’ — equivalent to, for example, warming an African country by 0.4 degrees Celsius for a year — caused a four per cent rise in the likelihood of personal violence and a 14 per cent increase in conflict between groups.

But now a team led by John O’Loughlin, a geographer at the University of Colorado Boulder in the United States, says that previous research may have overlooked other key triggers such as political instability, poverty and geographical conditions.

O’Loughlin’s team examined these factors alongside exceptionally hot or dry periods in Sub-Saharan Africa to assess the chances of increased violence. Breaking the area down into subregional grids, the researchers pinpointed 78,000 ‘conflict events’ from the past 33 years and matched them with weather conditions and social and geographical factors.

They found that conflicts such as riots, protests or violence against civilians were more common when temperatures were particularly high. But they also discovered an inconsistent relationship between temperature deviations on the one hand and different types of conflict and different subregions on the other.

And, more critically, they found that longer periods of higher temperatures and wet or dry conditions had less impact on conflict than other influences, such as recent nearby violence and a lack of democracy, says O’Loughlin....

A British jeep passes a sign warning against looting on the outskirts of Ravenna, Italy, 7 December 1944. From the Imperial War Museum