Thursday, April 3, 2014

Major increase in West Antarctic glacial loss

Date:
March 26, 2014
Source:
American Geophysical Union
Summary:
Six massive glaciers in West Antarctica are moving faster than they did 40 years ago, causing more ice to discharge into the ocean and global sea level to rise, according to new research.

The amount of ice draining collectively from those half-dozen glaciers increased by 77 percent from 1973 to 2013, scientists report this month in Geophysical Research Letters, a journal of the American Geophysical Union. Pine Island Glacier, the most active of the studied glaciers, has accelerated by 75 percent in 40 years, according to the paper. Thwaites Glacier, the widest glacier, started to accelerate in 2006, following a decade of stability.
A satellite image of Pine Island Glacier shows an 18-mile-long crack across the glacier. Researchers used cracks and other physical features on the glaciers to calculate glacier acceleration by comparing image data from year to year to see how far the cracks traveled.   Credit: NASA


"What we found was a sustained increase in ice discharge -- which has a significant impact on sea level rise," he said.The study is the first to look at the ice coming off the six most active West Antarctic glaciers over such an extended time period, said Jeremie Mouginot, a glaciologist at University of California-Irvine (UC-Irvine) who co-authored the paper. Almost 10 percent of the world's sea-level rise per year comes from just these six glaciers, he said.

The researchers studied the Pine Island, Thwaites, Haynes, Smith, Pope and Kohler glaciers, all of which discharge ice into a vast bay known as the Amundsen Sea Embayment in West Antarctica.
The amount of ice released by these six glaciers each year is comparable to the amount of ice draining from the entire Greenland Ice Sheet annually, Mouginot said. If melted completely, the glaciers' disappearance would raise sea levels another 1.2 meters (four feet), according to co-author and UC-Irvine Professor Eric Rignot.
The decades of increasing speeds and ice loss are "a strong indication of a major, long-term leakage of ice into the ocean from that sector of Antarctica," noted Rignot.
"This region is considered the potential leak point for Antarctica because of the low seabed. The only thing holding it in is the ice shelf," said Robert Thomas, a glaciologist at the NASA Wallops Flight Facility, in Wallops Island, Va., who was not involved in the study. Ice shelves are platforms of permanent floating ice that form where glaciers meet the sea. In West Antarctica, ice shelves prevent the glaciers investigated in the study from slipping more rapidly into the ocean.
Mouginot and his colleagues used satellite data to look at sequential images of the glaciers from 1973 to 2013. The scientists then calculated how fast the ice was moving by tracking surface features, such as cracks in the ice, to determine the distance the glaciers traveled from month to month and year to year.
While the study considered the six glaciers collectively, it also revealed unprecedented change on the individual glacier level. Thwaites Glacier, the largest of the six with a width of 120 kilometers (75 miles), experienced a decade of near-stability until 2006, when its speed picked up by 0.8 kilometers (half a mile) per year -- a 33 percent increase in speed, according to the study. This is the first time that such changes on Thwaites Glacier have been observed, said Mouginot.
Of all the glaciers in the study, Pine Island Glacier accelerated the most since 1973, increasing by 1.7 kilometers (one mile), per year. That's a 75 percent increase in speed from approximately 2.5 kilometers (1.5 miles) per year in 1973 to 4 kilometers (2.5 miles) per year in 2013.
Both Pine Island and Thwaites glaciers contribute the most to overall ice discharge -- about three-fourths of the total amount documented in the study. However, scientists also documented even higher rates of increased discharge in some of the smaller glaciers. Smith and Pope Glaciers nearly tripled the amount of ice they drained into the ocean since 1973.
The research team also found that the Pine Island Glacier is accelerating along its entire drainage system -- up to 230 kilometers (155 miles) inland from where it meets the ocean.
"This paper is important in showing that a glacier can actually 'feel' what is happening far downstream of itself," said Thomas. "It means that if you disturb the ice sheet near the coast, the glaciers will feel the push and rapidly respond hundreds of kilometers inland."
This finding suggests that glacier acceleration models may need to be reevaluated, Thomas added. Most current models only take into account isolated speed changes resulting from a local disturbance, rather than representing how these changes affect the glacier as a whole.
This research was funded by a grant from the NASA's Cryospheric Science Program and MEaSUREs program.
Story Source:
The above story is based on materials provided by American Geophysical Union.Note: Materials may be edited for content and length.
Journal Reference:
  1. J. Mouginot, E. Rignot, B. Scheuchl. Sustained increase in ice discharge from the Amundsen Sea Embayment, West Antarctica, from 1973 to 2013.Geophysical Research Letters, 2014; DOI: 10.1002/2013GL059069
Cite This Page:
American Geophysical Union. "Major increase in West Antarctic glacial loss." ScienceDaily. ScienceDaily, 26 March 2014. .
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Pesticides make the life of earthworms miserable

Date:
March 25, 2014 -  SCIENCE DAILY
Source:
University of Southern Denmark
Summary:
Pesticides are sprayed on crops to help them grow, but the effect on earthworms living in the soil under the plants is devastating, new research reveals. The worms only grow to half their normal weight and they do not reproduce as well as worms in fields that are not sprayed, a research team reports after having studied earthworms that were exposed to pesticides over generations.

Pesticides are sprayed on crops to help them grow, but the effect on earthworms living in the soil under the plants is devastating, new research reveals: The worms only grow to half their normal weight and they do not reproduce as well as worms in fields that are not sprayed.

Pesticides have a direct impact on the physiology and behavior of earthworms, a Danish/French research team reports after having studied earthworms that were exposed to pesticides over generations.
"We see that the worms have developed methods to detoxify themselves, so that they can live in soil sprayed with fungicide. They spend a lot of energy on detoxifying, and that comes with a cost: The worms do not reach the same size as other worms, and we see that there are fewer of them in sprayed soil. An explanation could be that they are less successful at reproducing, because they spend their energy on ridding themselves of the pesticide," the researchers, Ph. D. student Nicolas Givaudan and associate professor, Claudia Wiegand, say.
Claudia Wiegand is from the Department of Biology at University of Southern Denmark, and she led the research together with Francoise Binet from University Rennes 1 in France. Nicolas Givaudan is doing his Ph. D. as a joint degree between University of Southern Denmark and University of Rennes 1 in France. They researchers reached their findings by metabolomic profiling and energetic parameters.
The researchers set up an experiment to study the behavior of the earthworm species Aporectodea caliginosa. They moved two portions of farmed soil with worms into the lab. One portion was taken from a local organic field, the other from a local conventionally cultivated field that had been sprayed with fungicide for 20 years. This soil had remnants of the internationally commonly used fungicide Opus® at a level common in fields. When crops are sprayed with fungicide, only a small part of the chemical is absorbed by the plant. The waste can be up to 70 per cent, and much of the fungicide ends up in the soil.
In the laboratory, the researchers could see how the fungicide-exposed worms adapted to the toxic environment. Over generations the worms have developed a method to detoxify themselves.
"The fungicide increased metabolism rate in the worms, both the adapted worms and the not adapted worms. In the not adapted worms we saw that their energy reserve of glycogen was used faster. Contrastingly, only in the adapted worms we saw that amino acids and protein contents increased, suggesting a detoxification mechanism. "They also increased their feeding activity, possibly to compensate for the increase in energy demand," the researchers said.
Often there are 2 -- 3 times more earthworms in unsprayed soil than in sprayed soil.
"The reason for this may be that earthworms in sprayed soil do not reproduce as successfully as worms in unsprayed soil, because they need to spend more energy on detoxifying," the researchers say.
They also weighed the worms in the experiment and found that the worms exposed to fungicide weighed only half of the worms in organic soil. Worms in organic soil had an average weight of 0.6 grams, worms in conventionally cultivated soil had an average weight of 0.3 grams.
Story Source:
The above story is based on materials provided by University of Southern Denmark.Note: Materials may be edited for content and length.
Journal Reference:
  1. Nicolas Givaudan, Claudia Wiegand, Barbara Le Bot, David Renault, Fredérique Pallois, Stéphanie Llopis, Françoise Binet. Acclimation of earthworms to chemicals in anthropogenic landscapes, physiological mechanisms and soil ecological implications. Soil Biology and Biochemistry, 2014; 73: 49 DOI:10.1016/j.soilbio.2014.01.032
  2. Cite This Page:
    University of Southern Denmark. "Pesticides make the life of earthworms miserable." ScienceDaily. ScienceDaily, 25 March 2014. .
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Pesticides make the life of earthworms miserable

Date:
March 25, 2014
Source:
University of Southern Denmark
Summary:
Pesticides are sprayed on crops to help them grow, but the effect on earthworms living in the soil under the plants is devastating, new research reveals. The worms only grow to half their normal weight and they do not reproduce as well as worms in fields that are not sprayed, a research team reports after having studied earthworms that were exposed to pesticides over generations.

Pesticides are sprayed on crops to help them grow, but the effect on earthworms living in the soil under the plants is devastating, new research reveals: The worms only grow to half their normal weight and they do not reproduce as well as worms in fields that are not sprayed.

Pesticides have a direct impact on the physiology and behavior of earthworms, a Danish/French research team reports after having studied earthworms that were exposed to pesticides over generations.
"We see that the worms have developed methods to detoxify themselves, so that they can live in soil sprayed with fungicide. They spend a lot of energy on detoxifying, and that comes with a cost: The worms do not reach the same size as other worms, and we see that there are fewer of them in sprayed soil. An explanation could be that they are less successful at reproducing, because they spend their energy on ridding themselves of the pesticide," the researchers, Ph. D. student Nicolas Givaudan and associate professor, Claudia Wiegand, say.
Claudia Wiegand is from the Department of Biology at University of Southern Denmark, and she led the research together with Francoise Binet from University Rennes 1 in France. Nicolas Givaudan is doing his Ph. D. as a joint degree between University of Southern Denmark and University of Rennes 1 in France. They researchers reached their findings by metabolomic profiling and energetic parameters.
The researchers set up an experiment to study the behavior of the earthworm species Aporectodea caliginosa. They moved two portions of farmed soil with worms into the lab. One portion was taken from a local organic field, the other from a local conventionally cultivated field that had been sprayed with fungicide for 20 years. This soil had remnants of the internationally commonly used fungicide Opus® at a level common in fields. When crops are sprayed with fungicide, only a small part of the chemical is absorbed by the plant. The waste can be up to 70 per cent, and much of the fungicide ends up in the soil.
In the laboratory, the researchers could see how the fungicide-exposed worms adapted to the toxic environment. Over generations the worms have developed a method to detoxify themselves.
"The fungicide increased metabolism rate in the worms, both the adapted worms and the not adapted worms. In the not adapted worms we saw that their energy reserve of glycogen was used faster. Contrastingly, only in the adapted worms we saw that amino acids and protein contents increased, suggesting a detoxification mechanism. "They also increased their feeding activity, possibly to compensate for the increase in energy demand," the researchers said.
Often there are 2 -- 3 times more earthworms in unsprayed soil than in sprayed soil.
"The reason for this may be that earthworms in sprayed soil do not reproduce as successfully as worms in unsprayed soil, because they need to spend more energy on detoxifying," the researchers say.
They also weighed the worms in the experiment and found that the worms exposed to fungicide weighed only half of the worms in organic soil. Worms in organic soil had an average weight of 0.6 grams, worms in conventionally cultivated soil had an average weight of 0.3 grams.
Story Source:
The above story is based on materials provided by University of Southern Denmark.Note: Materials may be edited for content and length.
Journal Reference:
  1. Nicolas Givaudan, Claudia Wiegand, Barbara Le Bot, David Renault, Fredérique Pallois, Stéphanie Llopis, Françoise Binet. Acclimation of earthworms to chemicals in anthropogenic landscapes, physiological mechanisms and soil ecological implications. Soil Biology and Biochemistry, 2014; 73: 49 DOI:10.1016/j.soilbio.2014.01.032
Cite This Page:
University of Southern Denmark. "Pesticides make the life of earthworms miserable." ScienceDaily. ScienceDaily, 25 March 2014. .
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Forests crucial to green growth

Date:
March 21, 2014 SCIENCE DAILY
Source:
World Agroforestry Centre (ICRAF)
Summary:
The value of forests and tree-based ecosystems extends far beyond carbon sequestration; they are the foundation of sustainable societies. A new report promotes REDD+ and the Green Economy as together providing a new pathway to sustainable development that can benefit all nations. It claims this approach can conserve and even boost the economic and social benefits forests provide to human society.

The value of forests and tree-based ecosystems extends far beyond carbon sequestration; they are the foundation of sustainable societies.

A new report, launched in Jakarta, Indonesia on 21 March -- the International Day of Forests -- promotes REDD+ and the Green Economy as together providing a new pathway to sustainable development that can benefit all nations. It claims this approach can conserve and even boost the economic and social benefits forests provide to human society.
Building Natural Capital -- How REDD+ Can Support a Green Economy was developed by the International Resources Panel. It outlines how REDD+ can be integrated into a Green Economy to support pro-poor development while maintaining or increasing forest cover.
According to the report, REDD+ needs to be placed in a landscape-scale planning framework that goes beyond forests to consider all sectors of a modern economy and the needs of agriculture, energy, water resources, finance, transport, industry, trade and cities.
In this way, REDD+ would add value to other initiatives, such as agroforestry projects that are being implemented within these sectors, and be a critical element in a green economy.
The report provides recommendations on how to integrate REDD+ and Green Economy approaches, such as through better coordination, stronger private sector engagement, changes in fiscal incentive frameworks, greater focus on assisting policymakers to understand the role forests play in propping up economies, and equitable benefit sharing.
While it is recognized that what lies ahead is a long process of societies adapting to new conditions, REDD+ could be integral to increasing agricultural and forestry outputs to meet future needs, while at the same time enhancing the conservation of forests and ecosystem services.
Each year, the International Day of Forests highlights the unique role of forests in the environment and in sustaining livelihoods. The theme this year is Celebrating Forests for Sustainable Development.
"It is important day to remind us to save our planet as it is the only one we know which has trees says Tony Simons the Director General of the World Agroforestry Centre (ICRAF). "Trees are what made Earth habitable for mammals, and destruction of forests will lead to the ultimate destruction of mammals -- including humans. Trees are one of the few things which live longer than humans -- a true intergenerational gift. He added.
Forests and trees are key to sustainable development. Not only do they store carbon, they support biodiversity, regulate water flows and, reduce soil erosion. Nearly 1.6 billion people worldwide depend on forests as a source of food, medicines, timber and fuel.
Story Source:
The above story is based on materials provided by World Agroforestry Centre (ICRAF). Note: Materials may be edited for content and length.
Cite This Page:
World Agroforestry Centre (ICRAF). "Forests crucial to green growth." ScienceDaily. ScienceDaily, 21 March 2014. .


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Permafrost thaw exacerbates climate change

Date:
March 21, 2014 -  SCIENCE DAILY 
Source:
Woods Hole Research Center
Summary:
Growing season gains do not offset carbon emissions from permafrost thaw, new research shows. Permafrost contains three to seven times the amount of carbon sequestered in tropical forests. The warming climate threatens to thaw permafrost, which will result in the release of carbon dioxide and methane into the atmosphere creating feedback to climate change -- more warming and greater permafrost thaw.

The climate is warming in the arctic at twice the rate of the rest of the globe creating a longer growing season and increased plant growth, which captures atmospheric carbon, and thawing permafrost, which releases carbon into the atmosphere. Woods Hole Research Center (WHRC) Assistant Scientist Sue Natali and colleagues engineered first-of-a-kind warming experiments in the field to determine net gains or losses in carbon emissions. The study entitled "Permafrost degradation stimulates carbon loss from .
experimentally warmed tundra," published in the journal Ecology found that growing season gains do not offset carbon emissions from permafrost thaw.

According to Dr. Natali, "Our results show that while permafrost degradation increased carbon uptake during the growing season, in line with decadal trends of 'greening' tundra, warming and permafrost thaw also enhanced winter respiration, which doubled annual carbon losses."
Permafrost contains three to seven times the amount of carbon sequestered in tropical forests. The warming climate threatens to thaw permafrost, which will result in the release of carbon dioxide and methane into the atmosphere creating feedbacks to climate change -- more warming and greater permafrost thaw. Prior to this study, "the understanding of permafrost feedbacks to climate change had been limited by a lack of data examining warming effects on both vegetation and permafrost carbon simultaneously," said Dr. Natali.
This study measured CO2 emissions from permafrost thaw and its impact on the carbon balance on an ecosystem level. According to Dr. Natali, "There is 100 times more carbon stored belowground than aboveground in the arctic, so observed changes in plant productivity are only a very small component of the story. Given the amount of carbon stored belowground in the arctic, it is very unlikely that plant growth can ever fully offset C losses from permafrost thaw."
The three year long Carbon in Permafrost Experimental Heating Research (CiPEHR) project warmed air and soil and thawed permafrost using two warming experiments. The "winter warming" treatment consisted of snow packs, which functioned like down comforters insulating the ground during the winter until the snow was removed at the start of the growing season. The "summer warming" treatment consisted of open-topped greenhouses that warmed the air during the summer. The team measured warming effects on CO2 uptake by plants and release by plants and microbes.
Scientists estimate that within the next century permafrost will have declined 30% to 70% and there is limited accounting of how much carbon is stored in these frozen soils or the rate at which it will be released. For Dr. Natali:
"The only way we can accurately project future climate is to understand the responses of both plants and microbes to a warming climate. This study was the first to simulate whole ecosystem warming in the arctic, including permafrost degradation, similar to what is projected to happen as a result of climate change. There is a strong potential for significant global carbon emissions if rates calculated here become typical for permafrost ecosystems in a warmer world."
Story Source:
The above story is based on materials provided by Woods Hole Research Center.Note: Materials may be edited for content and length.
Journal Reference:
  1. Susan M. Natali, Edward A. G. Schuur, Elizabeth E. Webb, Caitlin E. Hicks Pries, Kathryn G. Crummer. Permafrost degradation stimulates carbon loss from experimentally warmed tundra. Ecology, 2014; 95 (3): 602 DOI: 10.1890/13-0602.1
Cite This Page:
Woods Hole Research Center. "Permafrost thaw exacerbates climate change." ScienceDaily. ScienceDaily, 21 March 2014. .


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Linking storms to climate change a 'distraction', say experts

Date:
March 20, 2014 - SCIENCE DAILY
Source:
Manchester University

Connecting extreme weather to climate change distracts from the need to protect society from high-impact weather events which will continue to happen irrespective of human-induced climate change, say experts.
Writing in the journal Weather, Climate and Society, the University of Manchester researchers argue that cutting greenhouse gas emissions, while crucial to reducing humanity's longer-term impact on the planet, will not eliminate violent storms, tornadoes or flooding and the damage they cause.
The authors suggest that developing greater resilience to extreme weather events must be given greater priority if the socioeconomic impact of storms, like those that have ravaged Britain this winter, is to be reduced.
Professor David Schultz, one of the authors of the guest editorial, said: "One of the long-term effects of climate change is often predicted to be an increase in the intensity and frequency of many high-impact weather events, so reducing greenhouse gas emissions is often seen to be the response to the problem.
"Reducing humanity's impact on our planet should be pursued as a matter of urgency, but more emphasis must also be placed on being resilient to individual weather events, as this year's storms in Britain have so devastatingly shown."
In the past, say the authors, society responded to weather disasters with calls for greater resilience, but public awareness of humanmade climate change has given climate timescales (decades and centuries) far greater importance than weather timescales (days and years)
Schultz, a professor of synoptic meteorology, and co-author Dr Vladimir Janković, a science historian specialising in weather and climate, say the short-term, large variability from year to year in high-impact weather makes it difficult, if not impossible, to draw conclusions about the correlation to longer-term climate change.
They argue that while large public investments in dams and flood defences, for example, must account for the possibilities of how weather might change in the future, this should not prevent short-term thinking to address more immediate vulnerability to inevitable high-impact weather events.
"Avoiding construction in floodplains, implementing strong building codes, and increasing preparedness can make society more resilient to extreme weather events," said Dr Janković. "But compounding the problem is that finding money for recovery is easier than spending on prevention, even if the costs of recovery are much higher."
This bias, say the authors, has a tendency to diminish the political dedication for preventative measures against extreme weather, regardless of whether they are caused or intensified by humanmade influences. Yet, steps taken to protect society from the weather can protect the planet as well, they argue.
Dr Janković said: "Improving forecasting, increasing preparedness or building better infrastructure can increase resilience and reduce carbon-dioxide emissions. For example, greening neighbourhoods or painting roofs lighter colours will both reduce the urban heat-island effect and reduce carbon-dioxide emissions through reduced air-conditioning costs, while making cities more resistant to storm damage would reduce emissions generated from rebuilding devastated areas."
Professor Schultz added: "Linking high-impact weather events with climate change can be distracting; perpetuating the idea that reducing greenhouse gases would be enough to reduce increasingly vulnerable world populations, in our view, only confuses the public and policy-makers as to the socio-economic susceptibility to extreme weather.
"With or without mitigation, there is no quick-fix, single-cause solution for the problem of human vulnerability to socio-environmental change, nor is there a reasonable prospect of attenuating high-impact weather. Addressing such issues would give the world an opportunity to develop a two-pronged policy in climate security, reducing longer-term climate risks in conjunction with preventing shorter-term weather disasters."
tory Source:
The above story is based on materials provided by Manchester University. Note: Materials may be edited for content and length.
Journal Reference:
  1. David M. Schultz, Vladimir Janković. Climate Change and Resilience to Weather Events. Weather, Climate, and Society, 2014; 140306133049007 DOI:10.1175/WCAS-D-14-00005.1
Cite This Page:
Manchester University. "Linking storms to climate change a 'distraction', say experts." ScienceDaily. ScienceDaily, 20 March 2014. .
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Race against time: Climate change and the Olympic Winter Games

Date:
March 21, 2014 - SCIENCE DAILY
Source:
Taylor & Francis

Time may be running out for some Olympic Winter Games host locations -- including the 2014 host, Sochi (Russia) -- according to an article in Current Issues in Tourism. Scott et al analyse two climatic indicators -- minimum temperature of ≤0°C and snow depth of ≥30cm -- both from a historical point of view and using future projections. They find that only 10 of the 19 previous host locations for the Winter Games are expected to remain suitable in the 2050s, and as few as 6 in the 2080s. This will have a major impact on where -- and how -- future Winter Games can be staged.
The Olympic Winter Games is a global mega-event. It is important not only for elite sporting competition, but also for tourism, media coverage, sponsorship and the promotion of culture. The Games can bring substantial benefits to a host city and region, and the bidding process to become a host is highly competitive. Climatic suitability is a key element in assessing locations, with weather conditions being critical for outdoor competitions, opening and closing ceremonies, the scheduling of events, spectator comfort and televised broadcasts.
Average February daytime temperatures of Winter Games locations have steadily increased, from 0.4°C in the period 1920-1950s, to 7.8°C in the twenty-first century. Given these trends, not all previous locations are likely to be suitable hosts for the Winter Games in future years.
Scott and colleagues focus on two specific conditions to assess the suitability of host locations, namely the probability that minimum daily temperatures will be 0°C or lower, and the probability that the snow depth will be 30cm or more (with snowmaking capacity). They classify each of the 19 previous host locations for three time periods: baseline (1981-2010), 2050s (representing 2041-2070) and 2080s (representing 2071-2100). They consider low- and high-emission scenarios for the two future periods. On the basis of how often these conditions were, or are expected to be, fulfilled, locations are classified as climatically reliable, marginal/high-risk, or unreliable.
In a high-emission scenario, less than a third (6 out of the 19) of the previous host locations are projected to be climatically reliable by the 2080s. This raises a number of issues for organisers of the Winter Games. Over the next two decades there may be a greater impetus to award the Winter Games to locations that are expected to become unreliable by the 2050s. If fewer regions of the world are climatically suitable, other regions that have not previously hosted the Games may need to be considered.
As Scott et al conclude: "In a substantially warmer world, celebrating the second centennial of the Olympic Winter Games in 2124 would become increasingly challenging." Organisers of the Games need to consider changes in the scale and format of future events, and investigate technologies that can overcome climate vulnerabilities.
Story Source:
The above story is based on materials provided by Taylor & Francis. Note: Materials may be edited for content and length.
Journal Reference:
  1. D. Scott, R. Steiger, M. Rutty, P. Johnson. The future of the Olympic Winter Games in an era of climate change. Current Issues in Tourism, 2014; 1 DOI:10.1080/13683500.2014.887664
Cite This Page:
Taylor & Francis. "Race against time: Climate change and the Olympic Winter Games." ScienceDaily. ScienceDaily, 21 March 2014. .
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