Friday, August 31, 2012

真英雄素食學苑 Real Hero Kitchen



网上素食烹饪教室 / Online Vegetarian cooking class

www.youtube.com/realherokitchen

欲知更多详情,请点击 / For more information, please click
http://www.realherokitchen.com.hk/online_lesson_youtube/online_lesson_youtube.htm







About 真英雄素食學苑
Real Hero Kitchen

真英雄素食學苑透過舉辦不同課程及活動,向公眾大力推廣吃素救地球的理念。

我們為何致力推廣及教授素食烹飪方面的知識?最大的原因是素食能即時消減80%以上全球暖化的情況,減溫室氣體的功效遠超其他生­活模式的改變。



新派素食不口寡 營養滿分啱爸媽

男女老少齊來學 幫助地球真到家

我們會每天製作及上載素菜烹飪短片,

敬請留意。BLOG:網誌

http://realherokitchen.mysinablog.com/

Link

Thursday, August 30, 2012

Large methane reservoirs beneath Antarctic ice sheet, study suggests

Large methane reservoirs beneath Antarctic ice sheet, study suggests

ScienceDaily (Aug. 29, 2012) — The Antarctic Ice Sheet could be an overlooked but important source of methane, a potent greenhouse gas, according to a report in the August 30 issue of Nature by an international team of scientists.
 
The new study demonstrates that old organic matter in sedimentary basins located beneath the Antarctic Ice Sheet may have been converted to methane by micro-organisms living under oxygen-deprived conditions. The methane could be released to the atmosphere if the ice sheet shrinks and exposes these old sedimentary basins.

Coauthor Slawek Tulaczyk, a professor of Earth and planetary sciences at UC Santa Cruz, said the project got its start five years ago in discussions with first author Jemma Wadham at the University of Bristol School of Geographical Sciences, where Tulaczyk was on sabbatical.

"It is easy to forget that before 35 million years ago, when the current period of Antarctic glaciations started, this continent was teeming with life," Tulaczyk said. "Some of the organic material produced by this life became trapped in sediments, which then were cut off from the rest of the world when the ice sheet grew. Our modeling shows that over millions of years, microbes may have turned this old organic carbon into methane."

The science team estimated that 50 percent of the West Antarctic Ice Sheet (1 million square kilometers) and 25 percent of the East Antarctic Ice Sheet (2.5 million square kilometers) overlies pre-glacial sedimentary basins containing about 21,000 billion metric tons of organic carbon.

"This is an immense amount of organic carbon, more than ten times the size of carbon stocks in northern permafrost regions," Wadham said. "Our laboratory experiments tell us that these sub-ice environments are also biologically active, meaning that this organic carbon is probably being metabolized to carbon dioxide and methane gas by microbes."

The researchers numerically simulated the accumulation of methane in Antarctic sedimentary basins using an established one-dimensional hydrate model. They found that sub-ice conditions favor the accumulation of methane hydrate (that is, methane trapped within a structure of water molecules, forming a solid similar to regular ice).

They also calculated that the potential amount of methane hydrate and free methane gas beneath the Antarctic Ice Sheet could be up to 4 billion metric tons, a similar order of magnitude to some estimates made for Arctic permafrost. The predicted shallow depth of these potential reserves also makes them more susceptible to climate forcing than other methane hydrate reserves on Earth.

Coauthor Sandra Arndt, a NERC fellow at the University of Bristol, who conducted the numerical modeling, said, "It's not surprising that you might expect to find significant amounts of methane hydrate trapped beneath the ice sheet. Just like in sub-seafloor sediments, it is cold and pressures are high, which are important conditions for methane hydrate formation."

If substantial methane hydrate and gas are present beneath the Antarctic Ice Sheet, methane release during episodes of ice-sheet collapse could act as a positive feedback on global climate change during past and future ice-sheet retreat.

"Our study highlights the need for continued scientific exploration of remote sub-ice environments in Antarctica, because they may have far greater impact on Earth's climate system than we have appreciated in the past," Tulaczyk said.

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Agriculture, food production among worst environmental offenders, report finds

Agriculture, food production among worst environmental offenders, report finds

ScienceDaily (June 9, 2010) — Earth is expected to be home to roughly 9 billion people by 2050 -- and everyone needs to eat. But a new report from the United Nations Environment Programme observes that growing and producing food make agriculture and food consumption among the most important drivers of environmental pressures, including climate change and habitat loss.

The report's lead author is Edgar Hertwich, a Professor of Energy and Process Engineering at the Norwegian University of Science and Technology.

The report, called "Assessing the Environmental Impacts of Consumption and Production: Priority Products and Materials" is the first-ever global-level assessment of the causes of different environmental pressures that result from economic activities. Professor Hertwich, who is director of NTNU's Industrial Ecology Programme, worked with colleagues for two years to develop detailed answers to three interrelated questions:

  • What are the most important industries that cause climate change?


  • How much energy do different consumption activities require when the production of the products  is taken into account?


  • What are the materials that contribute most to environmental problems?


  • Agriculture causes major environmental impacts
    Professor Hertwich said he was surprised to find that the environmental impacts of agriculture were greater than the production of materials such as cement and other manufactured goods. While the report does not make specific recommendations for change -- it is instead a detailed description of the problem -- Hertwich says, "it is clear that we can't all have a European average diet -- we just don't have the land and resources for that."

    The report itself observes that "impacts from agriculture are expected to increase substantially due to population growth, increasing consumption of animal products. Unlike fossil fuels, it is difficult to look for alternatives: people have to eat. A substantial reduction of impacts would only be possible with a substantial worldwide diet change, away from animal products."

    More income, more meat in our diets
    Another surprise was the effect of increasing economic affluence on different environmental impacts. The report authors found that environmental impacts increase approximately 80 per cent with the doubling of an individual's income. This increase results in part from a shift to a more meat-intensive diet.

    Another related problem -- and another surprise to Hertwich -- was the amount of food waste in both rich and poor countries. "Between 30 and 50 per cent of all food produced is spoiled or wasted," Hertwich said. "It's really quite surprising how much food waste there is." In poor countries, food is spoiled on the way to the market, while in rich countries, it spoils in people's refrigerators, he said.

    Hope for the future?
    Both Hertwich and international environmental officials say that people and policymakers must face the substantial environmental challenges facing all of humankind. In a press release from the UNEP, Ashok Khosla, co-chair of the Panel and President of the World Conservation Union (IUCN), is quoted as saying: "Incremental efficiency gains in, for example, motor cars or home heating systems have provided some improvements but, faced with the scale of the challenge, far more transformational measures need to be taken-- currently we are fiddling--or fiddling around the edges--while Rome burns."

    Hertwich agreed with Khosla's assessment. "There are fundamental challenges out there that I don't think that we as a society have woken up to yet," he said. "Somewhere in our rear-view mirror there is a big monster, and we are pretending it is not there. But I think if we really decide to tackle these challenges we will be able to do so."

    Hertwich has also developed a website that enables individuals to look at the Carbon Footprint of Nations (http://carbonfootprintofnations.com/). The report was released to coincide with the UN's Environment Day on June 5.

    The report is available at: http://www.unep.org/resourcepanel/documents/pdf/PriorityProductsAndMaterials_Report_Full.pdf
     
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    Hope of greater global food output, less environmental impact of agriculture

    Hope of greater global food output, less environmental impact of agriculture

    ScienceDaily (Aug. 29, 2012) — Can we have enough to eat and a healthy environment, too? Yes -- if we're smart about it, suggests a study published in Nature this week by a team of researchers from the University of Minnesota and McGill University in Montreal.

    Global demand for food is expected to double by 2050 due to population growth and increased standards of living. To meet this demand, it is often assumed we will need to expand the environmental burden of agriculture. The paper, based on analysis of agricultural data gathered from around the world, offers hope that with more strategic use of fertilizer and water, we could not only dramatically boost global crop yield, but also reduce the adverse environmental impact of agriculture.

    "We have often seen these two goals as a trade-off: We could either have more food, or a cleaner environment, not both," says lead author Nathaniel Mueller, a researcher with the University of Minnesota's Institute on the Environment and a doctoral student in the College of Food, Agricultural and Natural Resource Sciences. "This study shows that doesn't have to be the case."

    Mueller and colleagues used management and yield data for 17 major crops to take a big-picture look at how much water and nutrients it would take to bring under-performing farmlands to meet their food production potential. They also looked for places where fertilizer use could be cut down without substantially reducing crop yield. They found:

  • We could boost production 45 to 70 percent for most crops. The greatest opportunities for yield improvement are found in Eastern Europe, sub-Saharan Africa, East Asia, and South Asia.


  • Different inputs serve as limiting factors depending on the region and crop. Nutrients, for example, appear to be limiting corn production in Eastern Europe and West Africa and wheat production in Eastern Europe, while nutrients and water appear to limit rice production in Southeast Asia.


  • Worldwide, we could decrease nitrogen use 28 percent and phosphorus use 38 percent without adversely affecting yields for corn, wheat and rice. China stands out as a hot spot of nutrient overuse, but other areas, like the United States, Western Europe, and India, also have room to improve.


  • With strategic redistribution of nutrient inputs, we could bring under-performing lands worldwide to 75 percent of their production potential while only increasing global nitrogen use 9 percent and potassium use 34 percent -- and reducing phosphorus use 2 percent.


  • The researchers caution that their analysis is at a coarse scale and that many other factors, including land characteristics, use of organic fertilizers, economics, geopolitics, water availability and climate change will influence actual gains in crop production and reductions in adverse environmental impacts. Nevertheless, they are encouraged by the strong indication that closing the "yield gap" on under-performing lands -- previously identified as one of five promising points for meeting future food needs, along with halting farmland expansion in the tropics, using agricultural inputs more strategically, shifting diets and reducing food waste -- holds great promise for sustainably boosting food security.

    "These results show that substantial gains are indeed possible from closing the yield gap -- and combining these efforts with improved management of existing lands can potentially reduce agriculture's environmental impact," Mueller says. "They also offer concrete suggestions as to where and how we can focus future efforts. This work should serve as a source of great encouragement and motivation for those working to feed the 9-billion-plus people anticipated to live on this planet in 2050 while protecting Earth's indispensible life support systems."

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    Wednesday, August 29, 2012

    Society's response to climate change is critical

    Society's response to climate change is critical

    ScienceDaily (July 18, 2012) — Lancaster University (UK) scientists have proposed a new way of considering society's reactions to global warming by linking societal actions to temperature change.

    Using this framework to analyse climate change policies aimed at avoiding dangerous climate change, they suggest that society will have to become fifty times more responsive to global temperature change than it has been since 1990.

    The researchers, Dr Andy Jarvis, Dr David Leedal and Professor Nick Hewitt from the Lancaster Environment Centre, also show that if global energy use continues to grow as it has done historically, society would have to up its decarbonization efforts from its historic (160 year) value of 0.6% per year to 13% per year.

    Dr Andy Jarvis said: "In order to avoid dangerous climate change, society will have to become much more responsive to the risks and damages that growth in global greenhouse gas emissions impose."
    The research, published in Nature Climate Change on 15 July has found that the global growth of new renewable sources of energy since 1990 constitutes a climate-society feedback of a quarter percent per year in the growth rate of CO2 emissions per degree temperature rise.

    Professor Nick Hewitt said "If left unmanaged, the climate damages that we experience will motivate society to act to a greater or lesser degree. This could either amplify the growth in greenhouse gas emissions as we repair these damages or dampen them through loss of economic performance. Both are unpredictable and potentially dangerous."

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    Research reveals the true cost of a burger

    Research reveals the true cost of a burger

    ScienceDaily (Feb. 14, 2012) — The UK could considerably reduce its carbon footprint if more of us switched to a vegetarian diet, according to new research by Lancaster University.

    The report 'Relative greenhouse gas impacts of realistic dietary choices' published in the journal Energy Policy says that if everyone in the UK swapped their current eating habits for a vegetarian or vegan diet, our greenhouse gas emissions savings would be the equivalent of a 50 per cent reduction in exhaust pipe emissions from the entire UK passenger car fleet or 40m tonnes.

    From biscuits and bananas to beer and wine, everything in our shopping basket comes at a cost to the environment and each stage of food production -- from farming and transport to storage and packaging -results in greenhouse gas emissions.

    By working out the typical greenhouse gas emissions associated with the production of 61 different categories of food, using supermarket data supplied by Booths, the authors of the report, Professor Nick Hewitt of Lancaster University and Mike Berners-Lee of Small World Consulting, were able to work out the typical emissions associated with a number of different diets.

    They worked out that the combined greenhouse gas emissions from the foods we eat in the UK are the equivalent of 167 million tons of carbon dioxide equivalent, and switching to vegetarian or vegan diets could cut this by between 22 and 26 per cent.

    Fresh meat had the highest emissions of all, but meat and cheese had generally high greenhouse gas costs. These emissions were largely caused by methane from rumination, slurry and farm yard manure and nitrous oxide from fertilizer. Meat has a carbon footprint at the checkout of 17kg of carbon dioxide equivalent per kilogram. Cheese has 15kg. Cooked meats are also high at 11kg per kilogram, with bacon at 9kg.

    Exotic vegetables and mushrooms are high (9kg), largely because of freight and glasshouse heating costs. In contrast, fruit and vegetables grown without artificial heating and/ or were shipped to the UK by sea, have low emissions. Wine has a carbon footprint of 2kg per kilogram, and potatoes, apples, milk, bread and cereals are under 2kg.

    Professor Nick Hewitt said: "Greenhouse gases resulting from man's activities are changing the composition of the atmosphere, ultimately, with effects on global climate. It is clear that in order to meet the ambitious emissions reductions targets agreed in the UK and elsewhere, emissions from every possible source category have to be addressed and driven down. Food production, particularly by industrialised agricultural practices, causes significant greenhouse gas emissions. Realistic choices about diet can make substantial differences to embodied GHG emissions."

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    Arctic sea ice reaches lowest extent ever recorded

    Arctic sea ice reaches lowest extent ever recorded

    ScienceDaily (Aug. 27, 2012) — The blanket of sea ice floating on the Arctic Ocean melted to its lowest extent ever recorded since satellites began measuring it in 1979, according to the University of Colorado Boulder's National Snow and Ice Data Center.

    On Aug. 26, the Arctic sea ice extent fell to 1.58 million square miles, or 4.10 million square kilometers. The number is 27,000 square miles, or 70,000 square kilometers below the record low daily sea ice extent set Sept. 18, 2007. Since the summer Arctic sea ice minimum normally does not occur until the melt season ends in mid- to late September, the CU-Boulder research team expects the sea ice extent to continue to dwindle for the next two or three weeks, said Walt Meier, an NSID scientist.

    "It's a little surprising to see the 2012 Arctic sea ice extent in August dip below the record low 2007 sea ice extent in September," he said. "It's likely we are going to surpass the record decline by a fair amount this year by the time all is said and done."

    On Sept. 18, 2007, the September minimum extent of Arctic sea ice shattered all satellite records, reaching a five-day running average of 1.61 million square miles, or 4.17 million square kilometers. Compared to the long-term minimum average from 1979 to 2000, the 2007 minimum extent was lower by about a million square miles -- an area about the same as Alaska and Texas combined, or 10 United Kingdoms.

    While a large Arctic storm in early August appears to have helped to break up some of the 2012 sea ice and helped it to melt more quickly, the decline seen in in recent years is well outside the range of natural climate variability, said Meier. Most scientists believe the shrinking Arctic sea ice is tied to warming temperatures caused by an increase in human-produced greenhouse gases pumped into Earth's atmosphere.

    CU-Boulder researchers say the old, thick multi-year ice that used to dominate the Arctic region has been replaced by young, thin ice that has survived only one or two melt seasons -- ice which now makes up about 80 percent of the ice cover. Since 1979, the September Arctic sea ice extent has declined by 12 percent per decade.

    The record-breaking Arctic sea ice extent in 2012 moves the 2011 sea ice extent minimum from the second to the third lowest spot on record, behind 2007. Meier and his CU-Boulder colleagues say they believe the Arctic may be ice-free in the summers within the next several decades.
    "The years from 2007 to 2012 are the six lowest years in terms of Arctic sea ice extent in the satellite record," said Meier. "In the big picture, 2012 is just another year in the sequence of declining sea ice. We have been seeing a trend toward decreasing minimum Arctic sea ice extents for the past 34 years, and there's no reason to believe this trend will change."

    The Arctic sea ice extent as measured by scientists is the total area of all Arctic regions where ice covers at least 15 percent of the ocean surface, said Meier.

    Scientists say Arctic sea ice is important because it keeps the polar region cold and helps moderate global climate -- some have dubbed it "Earth's air conditioner." While the bright surface of Arctic sea ice reflects up to 80 percent of the sunlight back to space, the increasing amounts of open ocean there -- which absorb about 90 percent of the sunlight striking the Arctic -- have created a positive feedback effect, causing the ocean to heat up and contribute to increased sea ice melt.

    Earlier this year, a national research team led by CU embarked on a two-year effort to better understand the impacts of environmental factors associated with the continuing decline of sea ice in the Arctic Ocean. The $3 million, NASA-funded project led by Research Professor James Maslanik of aerospace engineering sciences includes tools ranging from unmanned aircraft and satellites to ocean buoys in order to understand the characteristics and changes in Arctic sea ice, including the Beaufort Sea and Canada Basin that are experiencing record warming and decreased sea ice extent.

    NSIDC is part of CU-Boulder's Cooperative Institute for Research in Environmental Sciences -- a joint institute of CU-Boulder and the National Oceanic and Atmospheric Administration headquartered on the CU campus -- and is funded primarily by NASA. NSIDC's sea ice data come from the Special Sensor Microwave Imager/Sounder sensor on the Defense Meteorological Satellite Program F17 satellite using methods developed at NASA's Goddard Space Flight Center in Greenbelt, Md.

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    Tuesday, August 28, 2012

    Livestock Raising: Devastating Forests and Driving Climate Change in Australia and Beyond

    Watch this video :
    http://suprememastertv.com/scientists-on-climate-change/?wr_id=170




    Gerard: Queensland has now produced a landmark report that shows 20 years of satellite monitoring of tree clearing. If you look at the average, 91% of all tree clearing has been clearing for livestock.




    HOST: Greetings, eco-conscious viewers, and welcome to Planet Earth: Our Loving Home. On this week’s program Australian scientists Gerard Bisshop and Dr. Clive McAlpine will discuss the severe environmental damage inflicted by livestock raising on our world, most notably deforestation and climate change.

    Mr. Bisshop recently retired from a position as a remote-sensing scientist with the Statewide Land-cover and Trees Study (SLATS) group mapping vegetation cover and tree-clearing rates across the state of Queensland, Australia.

    The group has published a landmark report tracing 20 years of
    deforestation in Queensland. In addition to his work on the SLATS report,
    Mr. Bisshop recently co-wrote a paper on the extremely harmful
    environmental and climatic effects of livestock grazing.

    The study will be presented at the Biennial Conference of the Australian Association of Environmental Education in September 2010.

    What we looked at was the common cause for land degradation, soil degradation, soil loss, biodiversity loss; that is trees and plants and animals being extinct. And loss of forests; that is deforestation. The common cause, in fact causing 91% of that is land clearing for raising livestock.

    HOST: Dr. McAlpine, an Associate Professor in the School of Geography, Planning and Environmental Management at The University of Queensland, Australia is lead author of a paper that concludes that beef consumption is the cause of serious environmental injury to the planet and a driver of climate change.
    The study was published last year in the interdisciplinary journal 『Global Environmental Change: Human and Policy Dimensions.』

    For more details on Dr. McAlpine, please visit
    www.GPEM.UQ.edu.au/Clive-McAlpine

    Monday, August 27, 2012

    Only two percent of Canadians deny climate change

    Only two percent of Canadians deny climate change

    ScienceDaily (Aug. 24, 2012) — Only two per cent of Canadians believe climate change is not occurring, a new important survey released August 24 by IPAC-CO2 Research Inc. concluded.

    The survey comes on the heels of Alberta Premier Alison Redford's recent push for a National Energy Strategy, which would address the future of Canada's oil and gas industries, and its approach to carbon management.

    "Our survey indicates that Canadians from coast to coast overwhelmingly believe climate change is real and is occurring, at least in part due to human activity" explained Dr. Carmen Dybwad, CEO of the environmental non-government organization said. "These findings have been consistent from 2011 and 2012. Canadians care about issues like extreme weather, drought and climate change."

    Opinions about the cause of climate change and how to combat it are, however, sharply divided among the provinces.

    "Canadians most commonly (54%) believe that climate change is occurring partially due to human activity and partially due to natural climate variation," said Briana Brownell of Insightrix Research, who conducted the survey for IPAC-CO2.

    "Residents of Quebec (44 %), Atlantic Canada (34%) and British Columbia (32 %) are more likely to believe climate change is occurring due to human activity than those on the Prairies (Alberta and Saskatchewan 21 %, Manitoba 24 %)."

    Canadians are also divided on what they believe should be the priorities to fight climate change.
    A total of 35 % of Canadians believe the priority should be to promote cleaner cars running on electricity or low-carbon fuels while only 16 % favored a tax on carbon dioxide emissions from the whole economy. Support for a carbon tax is lowest in B.C. (6%) and highest in Quebec (24%).

    A key solution cited by Canadians is Carbon Capture and Storage, or CCS, which involves capturing carbon dioxide from an industrial source of greenhouse gases, transporting it, and storing it deep in the Earth's subsurface.

    A majority of Canadians agree that capturing and storing carbon dioxide should be compulsory when building a new coal (59%) or natural gas (57%) power plant, though Canadians are concerned about the risks associated with CCS.

    Quebec residents (71 %) would be concerned if carbon dioxide was stored underground within 1.5 kilometres to 3 kilometres from their home, while Saskatchewan residents (43%) were the least worried.

    Residents of B.C. (60%) are most likely to believe that the storage of carbon dioxide represents a safety risk in the future. Again, Saskatchewan residents (48%) are significantly less likely to hold this belief.

    "CCS is not the "magic bullet" solution to combat climate change, but the development of CCS technology represents a necessary step in reducing Canada's emissions," said Dr. Dybwad.
    For a second consecutive year, IPAC-CO2 contracted Insightrix Research, Inc. to conduct an online survey of Canadian residents. Survey responses were collected from 1,550 Canadians between May 29 and June 11.

    The percentage of Canadians who are unsure whether or not they would benefit from CCS has increased notably from 42% in 2011 to 48% in 2012.

    Residents of Ontario are more likely to believe that it would (33%) benefit them, while in Quebec the reverse is true, where 30% believe they would not benefit from the technology.

    The proportion of Canadians who are unsure of the effectiveness of carbon capture and storage has increased notably from one quarter (24%) in 2011 to one third (35%) in 2012.

    Despite the concerns many Canadians have about the technology, Dr. Dybwad remains optimistic about the future of CCS and its impact on Canada's environment.

    "Canadians are concerned about the risks and benefits involved with CCS, but IPAC-CO2 exists to ensure that carbon dioxide is stored safely and permanently in the ground by providing risk and performance assessments of carbon dioxide storage projects."

    The 2012 survey on Public Awareness and Acceptance of CSS in Canada now is available on IPAC-CO2's website at: www.ipac-co2.com/research

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    Friday, August 24, 2012

    New climate history adds to understanding of recent Antarctic Peninsula warming

    New climate history adds to understanding of recent Antarctic Peninsula warming

    ScienceDaily (Aug. 22, 2012) — Results published this week by a team of polar scientists from Britain, Australia and France adds a new dimension to our understanding of Antarctic Peninsula climate change and the likely causes of the break-up of its ice shelves.

    The first comprehensive reconstruction of a 15,000 year climate history from an ice core collected from James Ross Island in the Antarctic Peninsula region is reported this week in the journal Nature. The scientists reveal that the rapid warming of this region over the last 100 years has been unprecedented and came on top of a slower natural climate warming that began around 600 years ago. These centuries of continual warming meant that by the time the unusual recent warming began, the Antarctic Peninsula ice shelves were already poised for the dramatic break-ups observed from the 1990's onwards.

    The Antarctic Peninsula is one of the fastest warming places on Earth -- average temperatures from meteorological stations near James Ross Island have risen by nearly 2°C in the past 50 years.

    Lead author Dr Robert Mulvaney OBE, from British Antarctic Survey (BAS) says, "This is a really interesting result. One of the key questions that scientists are attempting to answer is how much of the Earth's recently observed warming is due to natural climate variation and how much can be attributed to human activity since the industrial revolution. The only way we can do this is by looking back through time when the Earth experienced ice ages and warm periods, and ice cores are a very good method for doing this."

    Dr Mulvaney continues, "We know that something unusual is happening in the Antarctic Peninsula. To find out more we mounted a scientific expedition to collect an ice core from James Ross Island -- on the northernmost tip of the Peninsula. Within the 364m long core are layers of snow that fell every year for the last 50,000 years. Sophisticated chemical analysis -- at BAS and the NERC Isotope Geosciences Laboratory (part of British Geological Survey) -- was used to re-create a temperature record over this period.

    "For this study we looked in detail at the last 15,000 years -- from the time when the Earth emerged from the last ice age and entered into the current warm period. What we see in the ice core temperature record is that the Antarctic Peninsula warmed by about 6°C as it emerged from the last ice age. By 11,000 years ago the temperature had risen to about 1.3°C warmer than today's average and other research indicates that the Antarctic Peninsula ice sheet was shrinking at this time and some of the surrounding ice shelves retreated. The local climate then cooled in two stages, reaching a minimum about 600 years ago. The ice shelves on the northern Antarctic Peninsula expanded during this cooling. Approximately 600 years ago the local temperature started to warm again, followed by a more rapid warming in the last 50-100 years that coincides with present-day disintegration of ice shelves and glacier retreat."

    Co-Author Dr Nerilie Abram formerly from British Antarctic Survey and now with the Research School of Earth Sciences, at The Australian National University says, "The centuries of ongoing warming have meant that marginal ice shelves on the northern Peninsula were poised for the succession of collapses that we have witnessed over the last two decades. And if this rapid warming that we are now seeing continues, we can expect that ice shelves further south along the Peninsula that have been stable for thousands of years will also become vulnerable."

    Olivier Alemany, from the French Laboratoire de Glaciologie et Géophysique de l'Environnement was part of the expedition. He says, "The international polar science community has collected and analysed ice cores from Antarctica and Greenland as part of an effort to reconstruct the Earth's past climate and atmosphere. Our team wanted to understand how the recent warming and the loss of ice shelves compared to the longer term climate trends in the region."

    This research makes a significant contribution to the understanding of the role that Antarctica's ice sheets play in influencing future climate and sea-level rise. It was funded by NERC (Natural Environment Research Council).

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    Tuesday, August 21, 2012

    Extreme weather of last decade part of larger pattern linked to global warming

    Extreme weather of last decade part of larger pattern linked to global warming

    ScienceDaily (Mar. 25, 2012) — The past decade has been one of unprecedented weather extremes. Scientists of the Potsdam Institute for Climate Impact Research (PIK) in Germany argue that the high incidence of extremes is not merely accidental. From the many single events a pattern emerges. At least for extreme rainfall and heat waves the link with human-caused global warming is clear, the scientists show in a new analysis of scientific evidence in the journal Nature Climate Change. Less clear is the link between warming and storms, despite the observed increase in the intensity of hurricanes.

    In 2011 alone, the US was hit by 14 extreme weather events which caused damages exceeding one billion dollars each -- in several states the months of January to October were the wettest ever recorded. Japan also registered record rainfalls, while the Yangtze river basin in China suffered a record drought. Similar record-breaking events occurred also in previous years. In 2010, Western Russia experienced the hottest summer in centuries, while in Pakistan and Australia record-breaking amounts of rain fell. 2003 saw Europe´s hottest summer in at least half a millennium. And in 2002, the weather station of Zinnwald-Georgenfeld measured more rain in one day than ever before recorded anywhere in Germany -- what followed was the worst flooding of the Elbe river for centuries.

    A question of probabilities
    "The question is whether these weather extremes are coincidental or a result of climate change," says Dim Coumou, lead author of the article. "Global warming can generally not be proven to cause individual extreme events -- but in the sum of events the link to climate change becomes clear." This is what his analysis of data and published studies shows. "It is not a question of yes or no, but a question of probabilities," Coumou explains. The recent high incidence of weather records is no longer normal, he says.

    "It´s like a game with loaded dice," says Coumou. "A six can appear every now and then, and you never know when it happens. But now it appears much more often, because we have changed the dice." The past week illustrates this: between March 13th and 19th alone, historical heat records were exceeded in more than a thousand places in North America.

    Three pillars: basic physics, statistical analysis and computer simulations
    The scientists base their analysis on three pillars: basic physics, statistical analysis and computer simulations. Elementary physical principles already suggest that a warming of the atmosphere leads to more extremes. For example, warm air can hold more moisture until it rains out. Secondly, clear statistical trends can be found in temperature and precipitation data, the scientists explain. And thirdly, detailed computer simulations also confirm the relation between warming and records in both temperature and precipitation.

    With warmer ocean temperatures, tropical storms -- called typhoons or hurricanes, depending on the region -- should increase in intensity but not in number, according to the current state of knowledge. In the past decade, several record-breaking storms occurred, for example hurricane Wilma in 2004. But the dependencies are complex and not yet fully understood. The observed strong increase in the intensity of tropical storms in the North Atlantic between 1980 and 2005, for example, could be caused not just by surface warming but by a cooling of the upper atmosphere. Furthermore, there are questions about the precision and reliability of historic storm data.

    Overall, cold extremes decrease with global warming, the scientists found. But this does not compensate for the increase in heat extremes.

    Climatic warming can turn an extreme event into a record-breaking event
    "Single weather extremes are often related to regional processes, like a blocking high pressure system or natural phenomena like El Niño," says Stefan Rahmstorf, co-author of the article and chair of the Earth System Analysis department at PIK. "These are complex processes that we are investigating further. But now these processes unfold against the background of climatic warming. That can turn an extreme event into a record-breaking event."

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    Extreme weather linked to global warming, Nobel prize-winning scientist says

    Extreme weather linked to global warming, Nobel prize-winning scientist says

    ScienceDaily (Aug. 20, 2012) — New scientific analysis strengthens the view that record-breaking summer heat, crop-withering drought and other extreme weather events in recent years do, indeed, result from human activity and global warming, Nobel Laureate Mario J. Molina, Ph.D., said at a conference in Philadelphia on August 20.

    Molina, who shared the 1995 Nobel Prize in Chemistry for helping save the world from the consequences of ozone depletion, presented the keynote address at the 244th National Meeting & Exposition of the American Chemical Society.

    "People may not be aware that important changes have occurred in the scientific understanding of the extreme weather events that are in the headlines," Molina said. "They are now more clearly connected to human activities, such as the release of carbon dioxide ― the main greenhouse gas ― from burning coal and other fossil fuels."

    Molina emphasized that there is no "absolute certainty" that global warming is causing extreme weather events. But he said that scientific insights during the last year or so strengthen the link. Even if the scientific evidence continues to fall short of the absolute certainly measure, the heat, drought, severe storms and other weather extremes may prove beneficial in making the public more aware of global warming and the need for action, said Molina.

    "It's important that people are doing more than just hearing about global warming," he said. "People may be feeling it, experiencing the impact on food prices, getting a glimpse of what everyday life may be like in the future, unless we as a society take action."

    Molina, who is with the University of California, San Diego, suggested a course of action based on an international agreement like the Montreal Protocol that phased out substances responsible for the depletion of the ozone layer.

    "The new agreement should put a price on the emission of greenhouse gases, which would make it more economically favorable for countries to do the right thing. The cost to society of abiding by it would be less than the cost of the climate change damage if society does nothing," he said.

    In the 1970s and 1980s, Molina, F. Sherwood Rowland, Ph.D., and Paul J. Crutzen, Ph.D., established that substances called CFCs in aerosol spray cans and other products could destroy the ozone layer. The ozone layer is crucial to life on Earth, forming a protective shield high in the atmosphere that blocks potentially harmful ultraviolet rays in sunlight. Molina, Rowland and Crutzen shared the Nobel Prize for that research. After a "hole" in that layer over Antarctica was discovered in 1985, scientists established that it was indeed caused by CFCs, and worked together with policymakers and industry representatives around the world to solve the problem. The result was the Montreal Protocol, which phased out the use of CFCs in 1996.

    Adopted and implemented by countries around the world, the Montreal Protocol eliminated the major cause of ozone depletion, said Molina, and stands as one of the most successful international agreements. Similar agreements, such as the Kyoto Protocol, have been proposed to address climate change. But Molina said these agreements have largely failed.

    Unlike the ozone depletion problem, climate change has become highly politicized and polarizing, he pointed out. Only a small set of substances were involved in ozone depletion, and it was relatively easy to get the small number of stakeholders on the same page. But the climate change topic has exploded. "Climate change is a much more pervasive issue," he explained. "Fossil fuels, which are at the center of the problem, are so important for the economy, and it affects so many other activities. That makes climate change much more difficult to deal with than the ozone issue."

    In addition to a new international agreement, other things must happen, he said. Scientists need to better communicate the scientific facts underlying climate change. Scientists and engineers also must develop cheap alternative energy sources to reduce dependence on fossil fuels.
    Molina said that it's not certain what will happen to Earth if nothing is done to slow down or halt climate change. "But there is no doubt that the risk is very large, and we could have some consequences that are very damaging, certainly for portions of society," he said. "It's not very likely, but there is some possibility that we would have catastrophes."

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    Massachusetts butterflies move north as climate warms

    Massachusetts butterflies move north as climate warms

    ScienceDaily (Aug. 19, 2012) — The authors of a Harvard study published August 19 in Nature Climate Change gathered their data from an unlikely source -- the trip accounts of the Massachusetts Butterfly Club. During the past 19 years, the amateur naturalist group has logged species counts on nearly 20,000 expeditions throughout Massachusetts. Their records fill a crucial gap in the scientific record.

    Once analyzed, the data show a clear trend. "Over the past 19 years, a warming climate has been reshaping Massachusetts butterfly communities," notes Greg Breed, lead author on the study and a postdoctoral fellow at the Harvard Forest in Petersham.

    Subtropical and warm-climate species such as the giant swallowtail and zabulon skipper -- many of which were rare or absent in Massachusetts as recently as the late 1980s -- show the sharpest increases. At the same time, more than three-quarters of northerly species (species with a range centered north of Boston) are now declining in Massachusetts, many of them rapidly. Most impacted are the species that overwinter as eggs or small larvae, indicating that these overwintering stages may be much more sensitive to drought or lack of snow cover.

    The study creates new questions for managing threatened species. "For most butterfly species, climate change seems to be a stronger change-agent than habitat loss," says Breed. "Protecting habitat remains a key management strategy, and that may help some butterfly species. However, for many others, habitat protection will not mitigate the impacts of warming."

    Breed points to the frosted elfin, a species that receives formal habitat protection from the state. This southerly distributed butterfly is now one of the most rapidly increasing species in Massachusetts, with an estimated 1,000 percent increase since 1992. Some of this increase may be due to habitat protections, Breed allows. But over the same period, atlantis and aphrodite fritillaries, historically common summer butterflies in Massachusetts, have declined by nearly 90 percent -- yet these northerly species remain unprotected.

    The kind of information collected by the Massachusetts Butterfly Club is becoming increasingly valuable to scientists and land managers alike. Elizabeth Crone, senior ecologist at the Harvard Forest and another co-author on the study, notes, "Careful datasets from amateur naturalists play a valuable role in our understanding of species dynamics. Scientists constantly ask questions, but sometimes the data just isn't there to provide the answers, and we can't go back in time to collect it. This study would not have been possible without the dedication and knowledge of the data collectors on those 19,000 club trips."

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