Richard Black, BBC News 17 Nov 09;
Average temperatures across the world are on course to rise by up to 6C without urgent action to curb CO2 emissions, according a new analysis.
Emissions rose by 29% between 2000 and 2008, says the Global Carbon Project.
All of that growth came in developing countries, but a quarter of it came through production of goods for consumption in industrialised nations.
The study comes against a backdrop of mixed messages on the chances of a new deal at next month's UN climate summit.
According to lead scientist Corinne Le Quere, the new findings should add urgency to the political discussions.
"Based on our knowledge of recent trends and the time it takes to change energy infrastructure, I think that the Copenhagen conference next month is our last chance to stabilise at 2C in a smooth and organised way," she told BBC News.
"If the agreement is too weak or if the commitments are not respected, it's not two and a half or three degrees that we will get, it's five or six - that's the path that we are on right now."
Professor Le Quere, who holds posts at the UK's University of East Anglia and the British Antarctic Survey, is lead author on the study that is published in the journal Nature Geoscience.
Rising sinks
The Global Carbon Project (GCP) is a network of scientists in academic institutions around the world.
It uses just about every source of data available, from atmospheric observations to business inventories, to build up a detailed picture of carbon dioxide emissions, carbon sinks, and trends.
Before about 2002, global emissions grew by about 1% per year.
Then the rate increased to about 3% per year, the change coming mainly from a ramping up in China's economic output, before falling slightly in 2008 as the global economy dipped towards recession.
Endorsing similar projections from the International Energy Agency, the GCP suggests emissions will fall by about 3% during 2009 before resuming their rise as the recession ends.
Concentrations in the atmosphere also show an upward trend - as monitored at stations such as Mauna Loa in Hawaii - but at a lower rate.
The team believes that carbon sinks - the oceans and plants - are probably absorbing a slightly lower proportion of the carbon dioxide from fossil fuel emissions than they were 50 years ago, although researchers admit that uncertainty about the behaviour of sinks remains high.
Industrial emissions have climbed, but those from land use change have remains constant.
As a consequence, the proportion of global emissions coming from deforestation has fallen - about 12% now compared with 20% in the 1990s.
"One implication of this low fraction is that there is only limited scope for rich nations to offset emissions by supporting avoidance of deforestation in tropical countries like Indonesia and Brazil," observed Michael Rapauch from the Australian government research agency CSIRO and co-chair of the GCP.
A mechanism for Reducing Emissions from Deforestation and forest Degradation (REDD) is due to be concluded at next month's summit.
Future plans
Richard Betts, head of climate impacts at the UK Met Office and an author on the chapter of the 2007 Intergovernmental Panel on Climate Change (IPCC) report dealing with the effects of a changing atmosphere, suggested the report ought to be of interest to policymakers in the run-up to the Copenhagen summit.
"It's an important step towards understanding what we're doing to the world's carbon budget," he said.
However, he questioned the conclusion that society is necessarily on a trajectory leading towards 6C.
The IPCC plots out a number of "scenarios" - visions of how society might develop in terms of the size of the human population, economic growth and energy use - each of which comes with projected ranges of temperature rise.
Although the GCP study suggests society is on one of the high emission (and therefore high temperature rise) pathways, Dr Betts cautioned that it was too soon to discern a long-term trend.
"Year-to-year changes in the global economy have quite an effect, and it's too early to discern longer term, robust changes," he said.
"However, if we continue to let emissions rise without mitigation, there's a strong chance we'll hit 4C and beyond.
"If we want to be staying below 2C then it's true to say we've only got a few years to curb emissions."
These temperature rises - measured against a 19th Century baseline - would be expected to occur around the end of this century or the middle of next century, said Professor Le Quere.
Border controls
One of the most intriguing findings from the study is the difference between the emissions produced directly by a given nation and the emissions generated through production of the goods and services consumed by its citizens.
Emissions from within the UK's borders, for example, fell by 5% between 1992 and 2004, says the GCP analysis.
However, emissions from goods and services consumed in the UK rose by 12% over the same period.
"The developed world has exported to the developing world the emissions it would have produced had it met its growing appetite for consumer goods itself for the last two decades," said CSIRO's John Finnegan.
"In one sense, the developed world owns a large fraction of the developing world's emissions."
Another of the analyses shows that per-capita emissions across the globe are rising.
On average, each human now consumes goods and services "worth" 1.3 tonnes of carbon - up from 1.1 tonnes in 2000.
The GCP analysis suggests that constraining the global temperature rise to 2C would entail reducing per-capita emissions to 0.3 tonnes by 2050.
Fossil-fuel emissions up 2 percent in 2008, tracking worst trends
Yahoo News 17 Nov 09;
PARIS (AFP) – Carbon emissions from fossil fuels rose two percent last year to an all-time high, leaving Earth on a worst-scenario track for global warming, scientists reported on Tuesday.
They also voiced concern for the world's oceans and forests, saying the capacity of these fabled "sinks" to soak up dangerous greenhouse gases was fading.
And they placed the spotlight on surging emissions by China and developing countries, explaining that a huge chunk of this carbon comes from exporting goods that are consumed in rich nations.
The paper, published by the peer-reviewed journal Nature Geoscience, comes in the runup to December 7-18 UN talks in Copenhagen aimed at crafting a pact to combat climate change from 2013.
Global emissions from fossil fuels in 2008 amounted to 8.7 billion tonnes of carbon, an increase of two percent over 2007, the Global Carbon Project (GCP), gathering more than 30 climate specialists, reported.
The 2008 tally amounts to a decline over the average annual increase of 3.6 percent since the start of the decade, and can be pinned to the start of the world financial crisis, which triggered a fall in economic activity, it said.
Emissions last year were 29 percent higher than in 2000, reflecting a sprint in economic growth this decade, and a massive 41 percent greater than in 1990, the reference year for the UN's Kyoto Protocol.
Pollution "continued to track the average of the most carbon-intensive family of scenarios" put forward by the UN's Nobel-winning Intergovernmental Panel on Climate Change (IPCC), the paper warned.
Under the IPCC's "A1F1" scenario, Earth's surface will warm by around four degrees Celsius (7.2 degrees Fahrenheit) by 2100 compared with 2000 -- a rise consistent with a wipeout of species, widespread hunger, flooding, drought and homelessness.
The oceans and forests, which absorb most of the carbon dioxide (CO2) in the seas and through photosynthesis, are failing to keep up with the gigatonnes of emissions, said the researchers.
In the last 50 years, the proportion of CO2 pumped into the atmosphere that remains there has risen from about 40 to 45 percent, thus fuelling the greenhouse effect.
"This is of concern, as it indicates the vulnerability of the sinks to increasing emissions and climate change, making natural sinks less efficient 'cleaners' of human carbon pollution," said GCP Executive Director Pep Canadell of Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO).
The researchers also made these points:
-- developing countries now greatly outrank rich countries as the world's biggest source of carbon emissions, a switchover that occurred in 2005.
But a quarter of their growth in emissions can be accounted for by increased trade with the West. In China alone, 50 percent of the growth in emissions from 2002 to 2005 came from the country's export industries.
-- coal surpassed oil as an emissions source for the first time in recent decades. It accounted for 40 percent of CO2 from fossil fuels in 2008, compared with 36 percent for oil.
-- the share of deforestation and intensive farming in overall carbon gases has fallen. From 1990-2000, they accounted for 20 percent of the total; it was only 12 percent in 2008.
The reason: emissions from this sector fell from around 1.5 billion tonnes a year to 1.1 billion tonnes in 2008, thanks to fewer forest fires in Southeast Asia and lower-than-average deforestation in Amazonia. At the same time, emissions from oil, gas and coal rose.
-- worldwide CO2 emissions in 2009 are predicted to fall by 2.8 percent in response to the financial crisis, signalling a return to 2007 levels.
But emissions could rise anew, depending on a pickup in economic activity, efforts to improve energy efficiency and the outcome of talks to tackle climate change.
Global temperatures will rise 6C by end of century, say scientists
Most comprehensive CO2 study to date is expected to give greater urgency to diplomatic manoeuvring before Copenhagen
Alok Jha, guardian.co.uk 17 Nov 09;
Global temperatures are on a path to rise by an average of 6C by the end of the century as CO2 emissions increase and the Earth's natural ability to absorb the gas declines, according to a major new study.
Scientists said that CO2 emissions have risen by 29% in the past decade alone and called for urgent action by leaders at the UN climate talks in Copenhagen to agree drastic emissions cuts in order to avoid dangerous climate change.
The news will give greater urgency to the diplomatic manoeuvring before the Copenhagen summit. President Obama and President Hu of China attempted to breathe new life into the negotiations today by announcing that they intended to set targets for easing greenhouse gas emissions next month. Obama said that he and Hu would continue to press for a deal that would "rally the world".
The new study is the most comprehensive analysis to date of how economic changes and shifts in the way people have used the land in the past five decades have affected the concentration of CO2 in the atmosphere.
"The global trends we are on with CO2 emissions from fossil fuels suggest that we're heading towards 6C of global warming," said Corinne Le Quéré of the University of East Anglia who led the study with colleagues at the British Antarctic Survey.
"This is very different to the trend we need to be on to limit global climate change to 2C [the level required to avoid dangerous climate change]." That would require CO2 emissions from all sources to peak between 2015 and 2020 and that the global per capita emissions be decreased to 1 tonne of CO2 by 2050. Currently the average US citizen emits 19.9 tonnes per year and UK citizens emit 9.3 tonnes.
By studying 50 years of data on carbon emissions and combining with estimates of human carbon emissions and other sources such as volcanoes, the team was able to estimate how much CO2 is being absorbed naturally by forests, oceans and soil. The team conclude in the journal Nature Geoscience that those natural sinks are becoming less efficient, absorbing 55% of the carbon now, compared with 60% half a century ago. The drop in the amount absorbed is equivalent to 405m tonnes of carbon or around 60 times the annual output of Drax coal-fired power station, which is the largest in the UK.
"Based on our knowledge of recent trends in CO2 emissions and the time it takes to change energy infrastructure around the world and on the response of the sinks to climate change and variability, the Copenhagen conference is our last chance to stabilise climate at 2C above preindustrial levels in a smooth and organised way," said Le Quéré. "If the agreement is too weak or if the commitments are not respected, we will be on a path to 5C or 6C."
Le Quéré's work, part of the Global Carbon Project, showed that CO2 emissions from burning fossil fuels increased at an average of 3.4% a year between 2000 and 2008 compared with 1% a year in the 1990s. Despite the global economic downturn, emissions still increased by 2% in 2008. The vast majority of the recent increase has come from China and India, though a quarter of their emissions are a direct result of trade with the west. In recent years, the global use of coal has also surpassed oil.
Based on projected changes in GDP, the scientists said that emissions for 2009 were expected to fall to 2007 levels, before increasing again in 2010.
But Le Quéré's conclusion on the decline of the world's carbon sinks is not universally accepted. Wolfgang Knorr of the University of Bristol recently published a study in Geophysical Research Letters, using similar data to Le Quéré, where he argued that the natural carbon sinks had not noticeably changed. "Our apparently conflicting results demonstrate what doing cutting-edge science is really like and just how difficult it is to accurately quantify such data," said Knorr.
The amount of CO2 that natural carbon sinks can absorb varies from year to year depending on climactic and other natural conditions, and this means that overall trends can be difficult to detect. Le Quéré said her team's analysis had been able to remove more of the noise in the data that is associated with the natural annual variability of CO2 levels due to, for example, El Niño or volcanic eruptions. "Our methods are different – Knorr uses annual data, we use monthly data and I think we can remove more of the variability."
Jo House of the University of Bristol, who worked on the Nature Geoscience paper, said: "It is difficult to accurately estimate sources and sinks of CO2, particularly in emissions from land use change where data on the area and nature of deforestation is poor, and in modelled estimates of the land sink which is strongly affected by inter-annual climate variability. While the science has advanced rapidly, there are still gaps in our understanding."
The scientists agreed, however, that an improved understanding of land and ocean CO2 sinks was crucial, since it has a major influence in determining the link between human CO2 emissions and atmospheric concentration of the greenhouse gas. In turn, this has implications for CO2 targets set by governments at climate negotiations.
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