A carbon emission label or carbon label describes the carbon dioxide emissions embodied in a product. The world's first carbon label, which shows this carbon footprint embodied in a product in bringing it to the shelf, was introduced in the UK in 2006 by the Carbon Trust. Examples of products featuring their carbon footprint are Walkers Crisps, innocent Smoothies and Boots plc shampoos, which all featured the label from March 2007. By 2008 many other products featured the carbon reduction label including Tesco on an initial 20 own-range products such as orange juice and washing powder. HBOS feature it on their online bank account. The Carbon Trust label also requires companies to commit to reduce the embodied carbon in the labeled product or they lose the right to feature the label. An independent panel is currently verifying the process alongside Defra and the British Standards Institute BSI and a new standard PAS2050 is due to be introduced in mid-2008. As of August 2009, Defra is undertaking a radical rethink of the food industry on issues of security and sustainability, among many things proposing a green labelling scheme for food products.
Other versions now exist , one of them, the CarbonCounted version of the carbon label, which started in January 2007, uses a live carbon supply chain to determine the amount of carbon dioxide emitted to bring a product to market. This third party certified system, based on an open standard, eliminates the need for heavy auditing and guess work associated with values determined when using isolated accounting methods. This also addresses how to consistently and fairly apply the smaller details such as the heating, cooling, lighting etc. in the shops the products are sold in.
Another label initiative started in spring 2008 in Switzerland. The independent association climatop labels the most climate friendly products with their label «approved by climatop». In contrast to the label of Carbon Trust, this label does not indicate the carbon footprint of a specific product, it labels those products out of a comparable group of products with a remarkably lower carbon charge. As a rule of thumb, products have to be at least 20% better as other products from the same category. Therefore life cycle assessments or the products are calculated by independent offices, and the calculations are reviewed by a third party. Beside the fact that it has to be proven that those products have a lower climate charge, the products also have to fulfil several environmental and social standards. Examples of labeled products can be found at the Swiss retailer Migros, such as an organic fair trade sugar from Paraguay, recycling kitchen towels or laundry detergents.
California state representative Ira Ruskin sponsored a carbon labeling bill--the Carbon Labeling Act of 2009--in the California state legislature, which has been voted out of the Assembly Committee on Natural Resources. The act would require the State Air Resources Board to develop and implement a program for the voluntary assessment, verification, and standardized labeling of the carbon footprint of consumer products sold in the state.
Japan started launching a carbon footprint labelling scheme in 2008. The labels, to appear on dozens of items including food and drink, will provide detailed breakdowns of each product's carbon footprint under a government-approved calculation and labeling system.
In July 2009, Wal-Mart announced an environmental labeling program for its products. The intent is to create over the next five years a universal rating system, that scores products based on how environmentally and socially sustainable they are over the course of their lives. Wal-Mart’s goal is to have other retailers eventually adopt the indexing system.
From http://en.wikipedia.org/
Saturday, November 28, 2009
Friday, November 27, 2009
CO2 Australia Limited
CO2 Australia Limited (CO2 Australia) is Australia's largest provider of dedicated carbon sink plantings, established and managed for intended registration under formal emissions reduction schemes. It is the main operating entity of CO2 Group Limited (CO2 Group), which is a public company listed on the Australian Stock Exchange (ASX).
Dedicated forest carbon sink plantings provide a cost effective way to build a Carbon Bank for the future, allowing organisations to meet emissions management or environmental obligations. CO2 Australia manages over 12,500 hectares of carbon plantings across New South Wales, Victoria and Western Australia.
A fully accredited provider of carbon permits, CO2 Australia became the first reforestation company to be accredited under the NSW Greenhouse Gas Abatement Scheme (GGAS) in 2004. CO2 Australia is the provider of choice for organisations seeking to manage their greenhouse gas emissions profile, including under the Federal Government’s Carbon Pollution Reduction Scheme (CPRS). Credits under this scheme are fully auditable.
CO2 Australia works closely with the farming community across the Australian wheatbelt to integrate the mallee environmental plantings into existing farming and grazing systems. For a property to be considered suitable for use by CO2 Australia is must comply with the Kyoto Protocol, cleared of forest prior to 31 December 1989. Eligible forestry includes freehold land that receives a minimum of 350 millimeters average rainfall per annum that also provides over 50 hectares for mallee plantings.
CO2 Australia Carbon Sequestration Program™
Carbon sequestration is the process whereby trees absorb carbon dioxide in the roots, trunk, branches, twigs, bark and leaves as they grow and release oxygen back into the atmosphere. CO2 Australia makes arrangements to protect the trees for at least 100 years.
The CO2 Australia Carbon Sequestration Program™ improves biodiversity and reduces the risk of soil erosion and salinity. The program involves establishing long-term (great than 100 years) plantings of mallee eucalypts for the purpose of generating carbon permits, at a commercial scale unsurpassed in the industry.
CO2 Australia has conducted extensive research and development on the performance of the native mallee eucalypt trees used in carbon plantings. The mallees are long lived, drought tolerant, can survive intense fires and develops an extensive root system, allowing for a large, protected, underground carbon store. Through selective breeding, CO2 Australia has produced high performing seed lines, developed to have rapid rates of growth and carbon sequestration.
Company Background
In 2004, CO2 became the first reforestation company to be accredited under the New South Wales Greenhouse Gas Abatement Scheme (GGAS). From 2004 to 2005, CO2 Australia became a supplier of carbon credits for Origin Energy and Country Energy, and established forest carbon sinks for Eraring Energy in Australia.
CO2 Australia entered a joint venture with Macquarie Bank Limited to establish and manage a forest carbon sink in 2006. During the same year, CO2 was engaged by the Victorian Department of Sustainability and Environment to undertake plantings. CO2 Group also became the first Australian Associate Member and a listed Offset Provider under the Chicago Climate Exchange (CCX). CCX operates North America’s only cap and trade system for all six greenhouse gases, with global affiliates and projects worldwide.
In 2007, CO2 Australia became the first reforestation company to become an accredited abatement provider under the Australian Government’s Greenhouse Friendly™ program. In the following year, CO2 Australia announced projects for INPEX/Total Browse JV, Newmont Mining Corporation and Rip Curl. CO2 Australia also has contracts to establish and manage forest carbon sinks on behalf of Qantas Airways, Woodside Energy, the City of Sydney, EDS Australia and the Big Day Out.
CO2 Group Limited
CO2 Group Limited is a public company listed on the Australian Stock Exchange (ASX). The company specialises in the commercialisation of business opportunities within the environmental services sector. The formation of CO2 Australia, a Socially Responsible Investment Company, is CO2 Group’s first major initiative.
From http://en.wikipedia.org/
Dedicated forest carbon sink plantings provide a cost effective way to build a Carbon Bank for the future, allowing organisations to meet emissions management or environmental obligations. CO2 Australia manages over 12,500 hectares of carbon plantings across New South Wales, Victoria and Western Australia.
A fully accredited provider of carbon permits, CO2 Australia became the first reforestation company to be accredited under the NSW Greenhouse Gas Abatement Scheme (GGAS) in 2004. CO2 Australia is the provider of choice for organisations seeking to manage their greenhouse gas emissions profile, including under the Federal Government’s Carbon Pollution Reduction Scheme (CPRS). Credits under this scheme are fully auditable.
CO2 Australia works closely with the farming community across the Australian wheatbelt to integrate the mallee environmental plantings into existing farming and grazing systems. For a property to be considered suitable for use by CO2 Australia is must comply with the Kyoto Protocol, cleared of forest prior to 31 December 1989. Eligible forestry includes freehold land that receives a minimum of 350 millimeters average rainfall per annum that also provides over 50 hectares for mallee plantings.
CO2 Australia Carbon Sequestration Program™
Carbon sequestration is the process whereby trees absorb carbon dioxide in the roots, trunk, branches, twigs, bark and leaves as they grow and release oxygen back into the atmosphere. CO2 Australia makes arrangements to protect the trees for at least 100 years.
The CO2 Australia Carbon Sequestration Program™ improves biodiversity and reduces the risk of soil erosion and salinity. The program involves establishing long-term (great than 100 years) plantings of mallee eucalypts for the purpose of generating carbon permits, at a commercial scale unsurpassed in the industry.
CO2 Australia has conducted extensive research and development on the performance of the native mallee eucalypt trees used in carbon plantings. The mallees are long lived, drought tolerant, can survive intense fires and develops an extensive root system, allowing for a large, protected, underground carbon store. Through selective breeding, CO2 Australia has produced high performing seed lines, developed to have rapid rates of growth and carbon sequestration.
Company Background
In 2004, CO2 became the first reforestation company to be accredited under the New South Wales Greenhouse Gas Abatement Scheme (GGAS). From 2004 to 2005, CO2 Australia became a supplier of carbon credits for Origin Energy and Country Energy, and established forest carbon sinks for Eraring Energy in Australia.
CO2 Australia entered a joint venture with Macquarie Bank Limited to establish and manage a forest carbon sink in 2006. During the same year, CO2 was engaged by the Victorian Department of Sustainability and Environment to undertake plantings. CO2 Group also became the first Australian Associate Member and a listed Offset Provider under the Chicago Climate Exchange (CCX). CCX operates North America’s only cap and trade system for all six greenhouse gases, with global affiliates and projects worldwide.
In 2007, CO2 Australia became the first reforestation company to become an accredited abatement provider under the Australian Government’s Greenhouse Friendly™ program. In the following year, CO2 Australia announced projects for INPEX/Total Browse JV, Newmont Mining Corporation and Rip Curl. CO2 Australia also has contracts to establish and manage forest carbon sinks on behalf of Qantas Airways, Woodside Energy, the City of Sydney, EDS Australia and the Big Day Out.
CO2 Group Limited
CO2 Group Limited is a public company listed on the Australian Stock Exchange (ASX). The company specialises in the commercialisation of business opportunities within the environmental services sector. The formation of CO2 Australia, a Socially Responsible Investment Company, is CO2 Group’s first major initiative.
From http://en.wikipedia.org/
Wednesday, November 18, 2009
Diesel particulate matter
Diesel particulate matter (DPM), sometimes also called diesel exhaust particles (DEP), is the particulate component of diesel exhaust from older diesel cars, which includes diesel soot and aerosols such as ash particulates, metallic abrasion particles, sulfates, and silicates. When released into the atmosphere, DPM can take the form of individual particles or chain aggregates, with most in the invisible sub-micrometre range of 100 nanometers, also known as ultrafine particles (UFP) or PM0.1.
Health risks
The main particulate fraction of diesel exhaust consists of small particles. Because of their small size, inhaled particles may easily penetrate deep into the lungs. The rough surfaces of these particles makes it easy for them to bind with other toxins in the environment, thus increasing the hazards of particle inhalation. Exposures have been linked with acute short-term symptoms such as headache, dizziness, light-headedness, nausea, coughing, difficult or labored breathing, tightness of chest, and irritation of the eyes and nose and throat. Long-term exposures can lead to chronic, more serious health problems such as cardiovascular disease, cardiopulmonary disease, and lung cancer.
Exposure to diesel exhaust and DPM is a known occupational hazard to truckers, railroad workers, and miners using diesel-powered equipment in underground mines. Adverse health effects have also been observed in the general population at ambient atmospheric particle concentrations well below the concentrations in occupational settings.
Recently, concerns have been raised in the U.S. regarding children's exposure to DPM as they ride diesel-powered schoolbuses to and from school. The Environmental Protection Agency (EPA) has established the Clean School Bus USA initiative in an effort to unite private and public organizations in curbing student exposures.
Regulation
Although the American Mine Safety and Health Administration issued a health standard in January 2001 designed to reduce exposure in underground metal and nonmetal mines, on September 7, 2005, MSHA published a notice in the Federal Register proposing to postpone the effective date from January 2006 until January 2011.
From http://en.wikipedia.org/
Health risks
The main particulate fraction of diesel exhaust consists of small particles. Because of their small size, inhaled particles may easily penetrate deep into the lungs. The rough surfaces of these particles makes it easy for them to bind with other toxins in the environment, thus increasing the hazards of particle inhalation. Exposures have been linked with acute short-term symptoms such as headache, dizziness, light-headedness, nausea, coughing, difficult or labored breathing, tightness of chest, and irritation of the eyes and nose and throat. Long-term exposures can lead to chronic, more serious health problems such as cardiovascular disease, cardiopulmonary disease, and lung cancer.
Exposure to diesel exhaust and DPM is a known occupational hazard to truckers, railroad workers, and miners using diesel-powered equipment in underground mines. Adverse health effects have also been observed in the general population at ambient atmospheric particle concentrations well below the concentrations in occupational settings.
Recently, concerns have been raised in the U.S. regarding children's exposure to DPM as they ride diesel-powered schoolbuses to and from school. The Environmental Protection Agency (EPA) has established the Clean School Bus USA initiative in an effort to unite private and public organizations in curbing student exposures.
Regulation
Although the American Mine Safety and Health Administration issued a health standard in January 2001 designed to reduce exposure in underground metal and nonmetal mines, on September 7, 2005, MSHA published a notice in the Federal Register proposing to postpone the effective date from January 2006 until January 2011.
From http://en.wikipedia.org/
Saturday, November 14, 2009
Youth Climate Movement
The Youth Climate Movement is an international coalition of youth organisations. The coalitions aims to inspire, empower and mobilise a generational movement of young people across the world to take action on climate change. The movement itself is supported by the charity UNICEF.
History
In 2001, United States youth attending the preparations for the World Summit on Sustainable Development formed SustainUS, whose members began to attend the United Nations Framework Convention on Climate Change.
In June 2004, the Energy Action Coalition of America was formed, with 30 coalition partners, including SustainUS. Similar to the other Youth Climate Movements, the organisation has the objective of working together to leverage their collective power and create change for a clean, efficient, just and renewable energy future.
A year later from November 28 to December 9, 2005, the United Nations (UN) Climate Change Convention (COP 11 or COP/MOP 1) took place at the Palais des congrès de Montréal in Montréal, Quebec, Canada. Youth delegations from member nations, including the United States and Australia, attended, to advocate on behalf of young people. As a result, the concept of the Global Youth Climate Movement was first coined.
Following on from this in September 2006, the Canadian Youth Climate Coalition was launched, consisting of 48 youth organisations. This was soon followed by the Australian Youth Climate Coalition in November, which itself was a coalition of 27 youth organisations from across Australia.
In March 2008, the Indian Youth Climate Network joined the Global Youth Climate Movement whilst in June 2008, the United Kingdom ambassadors to the WWF's Voyage for the Future programme, Emma Biermann and Casper ter Kuile, created the UK Youth Climate Coalition (UKYCC), after returning from the Arctic to witness the impact of climate change. More recently, coalitions in Africa, China, Japan and South Asia have been formed with the same mission statement as the global movement.
Campaigns
Since 2005, the each country that participates in the Youth Climate Movement sends a youth delegation to the United Nations Climate Change Conference to represent young people in their respective country. Throughout the year, there are other opportunities for the members of the International Youth Climate Movement to convene. For example, at the International Youth Summit on Energy and Climate Change in Beijing, China and the Conference of Youth, which this year will take place from the 4-6 December 2009.
At the same time, each coalition organises their own events on climate change.
Main article: Power Shift
Power Shift is the name of an annual youth summit which has been held in Australia and the United States. The United Kingdom's version of the conference is scheduled for October 9 to October 12 at the Institute of Education in London. Power Shift Conferences are also being organised by other members of the International Youth Climate Movement including Canada, Japan and India. The focus of the events is on global warming and climate change policy.
Members
National members of the Youth Climate Movement include: the AYLCF Climate Action Network (France); Australian Youth Climate Coalition; Canadian Youth Climate Coalition; China Youth Climate Action Network; Energy Action Coalition (America); Ghana National Youth Coalition on Climate Change; Hong Kong Climate Change Coalition; Indian Youth Climate Network; Japan Youth Ecology League; Nature and Youth Denmark; Nigerian Youth Green Coalition on Climate Change; Russian Youth Climate Movement, SustainUS, and the UK Youth Climate Coalition. Each of these national organisations affiliate to other national organisations. For example, the UK Youth Climate Coalition includes the National Union of Students of the United Kingdom, the Otesha Project UK and You, Me & The Climate (YOMAC). Similarly, the Australian Youth Climate Coalition has over 27 members.
Each Climate Coalition or Climate Network is affiliated to a regional or continental movement such as the African Youth Initiative on Climate Change; Caribbean Youth Environmental Network; European Youth Climate Movement; Nordic Youth Climate Action Movement; North East Asia Youth Environmental Network; the South American Youth Climate Coalition and the South Asia Youth Environment Network.
Consequently, these local, national and continental organisations come together to form the International Youth Climate Movement.
From http://en.wikipedia.org/
History
In 2001, United States youth attending the preparations for the World Summit on Sustainable Development formed SustainUS, whose members began to attend the United Nations Framework Convention on Climate Change.
In June 2004, the Energy Action Coalition of America was formed, with 30 coalition partners, including SustainUS. Similar to the other Youth Climate Movements, the organisation has the objective of working together to leverage their collective power and create change for a clean, efficient, just and renewable energy future.
A year later from November 28 to December 9, 2005, the United Nations (UN) Climate Change Convention (COP 11 or COP/MOP 1) took place at the Palais des congrès de Montréal in Montréal, Quebec, Canada. Youth delegations from member nations, including the United States and Australia, attended, to advocate on behalf of young people. As a result, the concept of the Global Youth Climate Movement was first coined.
Following on from this in September 2006, the Canadian Youth Climate Coalition was launched, consisting of 48 youth organisations. This was soon followed by the Australian Youth Climate Coalition in November, which itself was a coalition of 27 youth organisations from across Australia.
In March 2008, the Indian Youth Climate Network joined the Global Youth Climate Movement whilst in June 2008, the United Kingdom ambassadors to the WWF's Voyage for the Future programme, Emma Biermann and Casper ter Kuile, created the UK Youth Climate Coalition (UKYCC), after returning from the Arctic to witness the impact of climate change. More recently, coalitions in Africa, China, Japan and South Asia have been formed with the same mission statement as the global movement.
Campaigns
Since 2005, the each country that participates in the Youth Climate Movement sends a youth delegation to the United Nations Climate Change Conference to represent young people in their respective country. Throughout the year, there are other opportunities for the members of the International Youth Climate Movement to convene. For example, at the International Youth Summit on Energy and Climate Change in Beijing, China and the Conference of Youth, which this year will take place from the 4-6 December 2009.
At the same time, each coalition organises their own events on climate change.
Main article: Power Shift
Power Shift is the name of an annual youth summit which has been held in Australia and the United States. The United Kingdom's version of the conference is scheduled for October 9 to October 12 at the Institute of Education in London. Power Shift Conferences are also being organised by other members of the International Youth Climate Movement including Canada, Japan and India. The focus of the events is on global warming and climate change policy.
Members
National members of the Youth Climate Movement include: the AYLCF Climate Action Network (France); Australian Youth Climate Coalition; Canadian Youth Climate Coalition; China Youth Climate Action Network; Energy Action Coalition (America); Ghana National Youth Coalition on Climate Change; Hong Kong Climate Change Coalition; Indian Youth Climate Network; Japan Youth Ecology League; Nature and Youth Denmark; Nigerian Youth Green Coalition on Climate Change; Russian Youth Climate Movement, SustainUS, and the UK Youth Climate Coalition. Each of these national organisations affiliate to other national organisations. For example, the UK Youth Climate Coalition includes the National Union of Students of the United Kingdom, the Otesha Project UK and You, Me & The Climate (YOMAC). Similarly, the Australian Youth Climate Coalition has over 27 members.
Each Climate Coalition or Climate Network is affiliated to a regional or continental movement such as the African Youth Initiative on Climate Change; Caribbean Youth Environmental Network; European Youth Climate Movement; Nordic Youth Climate Action Movement; North East Asia Youth Environmental Network; the South American Youth Climate Coalition and the South Asia Youth Environment Network.
Consequently, these local, national and continental organisations come together to form the International Youth Climate Movement.
From http://en.wikipedia.org/
Sunday, November 8, 2009
World Wide Views on Global Warming
World Wide Views on Global Warming is a global project initiated by The Danish Board of Technology on the occasion of the United Nations Climate Change Conference (COP15) held in Copenhagen December 2009.
World Wide Views on Global Warming (or just WWViews) is an international citizens involvement project based on methods developed by The Danish Board of Technology for the purpose of involving citizens in the political decision-making processes.
The WWViews Method
The World Wide Views project meetings are carried through on September 26 in 2009 at the same time in all the participating countries and on this day the citizens are going to debate the same topics issued at the actual Climate Change Conference in December the same year. On the basis of an informed and structured dialogue and expert presentations the citizens – 100 in each country – are thus going to make up their minds about a range of questions and dilemmas concerning different aspects of the climate debate. The results will be uploaded throughout the day and are publicly available almost in real time. Some answers will be quantifiable, permitting statistical comparison, but contrary to regular surveys the methods used for WWViews also give participants the option of discussing questions externally and further qualifying the answers.
World Wide Views on Global Warming gives citizens across the globe the possibility to influence political decisions in regard to the planet’s climate, because the meetings present citizens with the opportunity to express how far they are willing to let politicians go in the struggle to reduce CO2 emission.
The WWViews Partners
34 partners from 28 countries across the world have joined the World Wide Views on Global Warming and the number of project partners continues to expand.
From http://en.wikipedia.org/
World Wide Views on Global Warming (or just WWViews) is an international citizens involvement project based on methods developed by The Danish Board of Technology for the purpose of involving citizens in the political decision-making processes.
The WWViews Method
The World Wide Views project meetings are carried through on September 26 in 2009 at the same time in all the participating countries and on this day the citizens are going to debate the same topics issued at the actual Climate Change Conference in December the same year. On the basis of an informed and structured dialogue and expert presentations the citizens – 100 in each country – are thus going to make up their minds about a range of questions and dilemmas concerning different aspects of the climate debate. The results will be uploaded throughout the day and are publicly available almost in real time. Some answers will be quantifiable, permitting statistical comparison, but contrary to regular surveys the methods used for WWViews also give participants the option of discussing questions externally and further qualifying the answers.
World Wide Views on Global Warming gives citizens across the globe the possibility to influence political decisions in regard to the planet’s climate, because the meetings present citizens with the opportunity to express how far they are willing to let politicians go in the struggle to reduce CO2 emission.
The WWViews Partners
34 partners from 28 countries across the world have joined the World Wide Views on Global Warming and the number of project partners continues to expand.
From http://en.wikipedia.org/
Friday, November 6, 2009
Western Fuels Association
The Western Fuels Association is a not-for profit cooperative that supplies coal and transportation services to consumer-owned electric utility in the Great Plains, Rocky Mountain and Southwest regions. It is based in Westminster, Colorado.
Controversy
The Western Fuels Association has played a controversial role in the debate over global warming. Their 2005 Annual report refers only to 'environmental and regulatory uncertainty', but they have been more outspoken in past annual reports. They have established groups such as the Greening Earth Society which promote various forms of climate change skepticism and have funded individual skeptics, such as Patrick Michaels, Craig D. Idso and Sherwood Idso. Groups established by industry bodies like the Western Fuels Association have been criticized as Astroturf organizations, since they appear superficially to be grassroots initiatives.
From http://en.wikipedia.org/
Controversy
The Western Fuels Association has played a controversial role in the debate over global warming. Their 2005 Annual report refers only to 'environmental and regulatory uncertainty', but they have been more outspoken in past annual reports. They have established groups such as the Greening Earth Society which promote various forms of climate change skepticism and have funded individual skeptics, such as Patrick Michaels, Craig D. Idso and Sherwood Idso. Groups established by industry bodies like the Western Fuels Association have been criticized as Astroturf organizations, since they appear superficially to be grassroots initiatives.
From http://en.wikipedia.org/
Monday, November 2, 2009
West Antarctic Ice Sheet
The West Antarctic Ice Sheet (WAIS) is the segment of the continental ice sheet that covers West (or Lesser) Antarctica, the portion of Antarctica west of the Transantarctic Mountains. The WAIS is classified as a marine-based ice sheet, meaning that its bed lies well below sea level and its edges flow into floating ice shelves. The WAIS is bounded by the Ross Ice Shelf, the Ronne Ice Shelf, and outlet glaciers that drain into the Amundsen Sea.
Description
It is estimated that the volume of the Antarctic ice sheet is about 25.4 million km3, and the WAIS contains just under 10% of this, or 2.2 million km3. The weight of the ice has caused the underlying rock to sink by between 0.5 and 1 kilometres in a process known as isostatic depression.
Under the force of its own weight, the ice sheet deforms and flows. The interior ice flows slowly over rough bedrock. In some circumstances, ice can flow faster in ice streams, separated by slow-flowing ice ridges. The inter-stream ridges are frozen to the bed while the bed beneath the ice streams consists of water-saturated sediments. Many of these sediments were deposited before the ice sheet occupied the region, when much of West Antarctica was covered by the ocean. The rapid ice-stream flow is a non-linear process still not fully understood; streams can start and stop for unclear reasons.
When ice reaches the coast, it will continue to flow outward onto the water. The result is a large, floating shelf of ice affixed to the continent.
Potential collapse
Large parts of the WAIS sit on a reverse-sloping bed below sea level. The reverse slope, and the low isostatic head, means that the ice sheet is theoretically unstable: a small retreat could in theory destabilize the entire WAIS leading to rapid disintegration. Current computer models do not include the physics necessary to simulate this process, and observations do not provide guidance, so predictions as to its rate of retreat remain uncertain. This has been known for decades.
In January 2006, in a UK government-commissioned report, the head of the British Antarctic Survey, Chris Rapley, warned that this huge west Antarctic ice sheet may be starting to disintegrate. It has been hypothesised that this disintegration could raise sea levels by approximately 3.3 metres (10 ft). Although if the entire West Antarctic Ice Sheet was to melt this would contribute 4.8 m to global sea level. Rapley said a previous Intergovernmental Panel on Climate Change report playing down worries about the ice sheet's stability should be revised. "The last IPCC report characterized Antarctica as a slumbering giant in terms of climate change," he wrote. "I would say it is now an awakened giant. There is real concern." Note that the IPCC report did not use the words "slumbering giant".
Rapley said, "Parts of the Antarctic ice sheet that rest on bedrock below sea level have begun to discharge ice fast enough to make a significant contribution to sea level rise. Understanding the reason for this change is urgent in order to be able to predict how much ice may ultimately be discharged and over what timescale. Current computer models do not include the effect of liquid water on ice sheet sliding and flow, and so provide only conservative estimates of future behaviour."
James Hansen, a senior NASA scientist who is a leading climate adviser to the US government, said the results were deeply worrying. "Once a sheet starts to disintegrate, it can reach a tipping point beyond which break-up is explosively rapid," he said.
Indications that the West Antarctic Ice Sheet is losing mass at an increasing rate come from the Amundsen Sea sector, and three glaciers in particular: the Pine Island, Thwaites and Smith Glaciers. Data reveal they are losing more ice than is being replaced by snowfall. According to a preliminary analysis, the difference between the mass lost and mass replaced is about 60%. The melting of these three glaciers alone is contributing an estimated 0.24 millimetres per year to the rise in the worldwide sea level. There is growing evidence that this trend is accelerating: there has been a 75% increase in Antarctic ice mass loss in the ten years 1996-2006, with glacier acceleration a primary cause.
Polar ice experts from the U.S. and U.K. met at the University of Texas at Austin in March, 2007 for the West Antarctic Links to Sea-Level Estimation (WALSE) Workshop. The experts discussed a new hypothesis that explains the observed increased melting of the West Antarctic Ice Sheet. They proposed that changes in air circulation patterns have led to increased upwelling of warm, deep ocean water along the coast of Antarctica and that this warm water has increased melting of floating ice shelves at the edge of the ice sheet. An ocean model has shown how changes in winds can help channel the water along deep troughs on the sea floor, toward the ice shleves of outlet glaciers. The exact cause of the changes in circulation patterns is not known and they may be due to natural variability. However, this connection between the atmosphere and upwelling of deep ocean water provides a mechanism by which human induced climate changes could cause an accelerated loss of ice from WAIS. Recently published data collected from satellites support this hypothesis, suggesting that the west Antarctic ice sheet is beginning to show signs of instability.
Warming
The West Antarctic ice sheet has warmed by more than 0.1 °C/decade in the last 50 years, and is strongest in winter and spring. Although this is partly offset by fall cooling in East Antarctica, this effect is restricted to the 1980s and 1990s. The continent-wide average surface temperature trend of Antarctica is positive and significant at >0.05°C/decade since 1957. This warming of WAIS is strongest in the Antarctic Peninsula.
From http://en.wikipedia.org/
Description
It is estimated that the volume of the Antarctic ice sheet is about 25.4 million km3, and the WAIS contains just under 10% of this, or 2.2 million km3. The weight of the ice has caused the underlying rock to sink by between 0.5 and 1 kilometres in a process known as isostatic depression.
Under the force of its own weight, the ice sheet deforms and flows. The interior ice flows slowly over rough bedrock. In some circumstances, ice can flow faster in ice streams, separated by slow-flowing ice ridges. The inter-stream ridges are frozen to the bed while the bed beneath the ice streams consists of water-saturated sediments. Many of these sediments were deposited before the ice sheet occupied the region, when much of West Antarctica was covered by the ocean. The rapid ice-stream flow is a non-linear process still not fully understood; streams can start and stop for unclear reasons.
When ice reaches the coast, it will continue to flow outward onto the water. The result is a large, floating shelf of ice affixed to the continent.
Potential collapse
Large parts of the WAIS sit on a reverse-sloping bed below sea level. The reverse slope, and the low isostatic head, means that the ice sheet is theoretically unstable: a small retreat could in theory destabilize the entire WAIS leading to rapid disintegration. Current computer models do not include the physics necessary to simulate this process, and observations do not provide guidance, so predictions as to its rate of retreat remain uncertain. This has been known for decades.
In January 2006, in a UK government-commissioned report, the head of the British Antarctic Survey, Chris Rapley, warned that this huge west Antarctic ice sheet may be starting to disintegrate. It has been hypothesised that this disintegration could raise sea levels by approximately 3.3 metres (10 ft). Although if the entire West Antarctic Ice Sheet was to melt this would contribute 4.8 m to global sea level. Rapley said a previous Intergovernmental Panel on Climate Change report playing down worries about the ice sheet's stability should be revised. "The last IPCC report characterized Antarctica as a slumbering giant in terms of climate change," he wrote. "I would say it is now an awakened giant. There is real concern." Note that the IPCC report did not use the words "slumbering giant".
Rapley said, "Parts of the Antarctic ice sheet that rest on bedrock below sea level have begun to discharge ice fast enough to make a significant contribution to sea level rise. Understanding the reason for this change is urgent in order to be able to predict how much ice may ultimately be discharged and over what timescale. Current computer models do not include the effect of liquid water on ice sheet sliding and flow, and so provide only conservative estimates of future behaviour."
James Hansen, a senior NASA scientist who is a leading climate adviser to the US government, said the results were deeply worrying. "Once a sheet starts to disintegrate, it can reach a tipping point beyond which break-up is explosively rapid," he said.
Indications that the West Antarctic Ice Sheet is losing mass at an increasing rate come from the Amundsen Sea sector, and three glaciers in particular: the Pine Island, Thwaites and Smith Glaciers. Data reveal they are losing more ice than is being replaced by snowfall. According to a preliminary analysis, the difference between the mass lost and mass replaced is about 60%. The melting of these three glaciers alone is contributing an estimated 0.24 millimetres per year to the rise in the worldwide sea level. There is growing evidence that this trend is accelerating: there has been a 75% increase in Antarctic ice mass loss in the ten years 1996-2006, with glacier acceleration a primary cause.
Polar ice experts from the U.S. and U.K. met at the University of Texas at Austin in March, 2007 for the West Antarctic Links to Sea-Level Estimation (WALSE) Workshop. The experts discussed a new hypothesis that explains the observed increased melting of the West Antarctic Ice Sheet. They proposed that changes in air circulation patterns have led to increased upwelling of warm, deep ocean water along the coast of Antarctica and that this warm water has increased melting of floating ice shelves at the edge of the ice sheet. An ocean model has shown how changes in winds can help channel the water along deep troughs on the sea floor, toward the ice shleves of outlet glaciers. The exact cause of the changes in circulation patterns is not known and they may be due to natural variability. However, this connection between the atmosphere and upwelling of deep ocean water provides a mechanism by which human induced climate changes could cause an accelerated loss of ice from WAIS. Recently published data collected from satellites support this hypothesis, suggesting that the west Antarctic ice sheet is beginning to show signs of instability.
Warming
The West Antarctic ice sheet has warmed by more than 0.1 °C/decade in the last 50 years, and is strongest in winter and spring. Although this is partly offset by fall cooling in East Antarctica, this effect is restricted to the 1980s and 1990s. The continent-wide average surface temperature trend of Antarctica is positive and significant at >0.05°C/decade since 1957. This warming of WAIS is strongest in the Antarctic Peninsula.
From http://en.wikipedia.org/
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