FINDINGS
Content analysis indicates that the worse problem is not the warming caused by carbon dioxide itself, but the potential positive feedback loops in methane and water vapour levels that could be the consequences of the warming. The indicators also suggest that the unprecedented nature of this phase of climate change means that the science is very uncertain, and that nobody really knows what is going to happen. The corollary is that anyone who says they know, doesn’t.
Carbon dioxide
Issues: CLARIFYING DISAGREEMENTS
Most people agree with the scientific theory that carbon dioxide reflects heat that would otherwise radiate into space back into the atmosphere. There is also a widespread consensus that the concentration of carbon dioxide in the atmosphere is growing at an accelerating rate. Where people disagree are on the causes – human or non-human – and on the effects, forecasting how the increasing concentrations of CO2 will actually effect the climate. The truth is that nobody really knows, for sure. This meta-synthesis provides the latest indications of Conditions (what is happening), Goals (what we want to do), Actions (what we are actually doing).
Conditions: WORSE THAN HIGHEST FORECAST
CO2 emissions are reported as “exceeding the highest assumptions” in climate change studies, as between 2000 and 2004, worldwide CO2 emissions increased at a rate that is over three times the rate during the 1990s. According to the Proceedings of the US National Academy of Sciences, the rate increased from 1.1 per cent per year during the 1990s to 3.1 per cent per year in the early 2000s. The latest UN report on climate change states that emissions grew by more than 70 per cent between 1970 and 2004.
Goals: GETTING THERE IS HALF THE FUN
The Website www.terradaily.com estimates that by reducing deforestation rates by 50 per cent over the next century could contribute 12 per cent of the total carbon emissions reduction required to meet the target of stabilising atmospheric carbon dioxide to 450 part per million, the IPCC target. The New Scientist quotes the UN reports conclusion that “Stabilising greenhouse gases at a level that would limit global warming to between 2°C and 4°C will cost between 0.2% and 3.0% of annual GDP.”
Actions: MARKETS FAILING
In a Financial Times interview (www.ft.com), Chris Goodall, characterised as a “climate change guru”, is quoted saying that most carbon offsetting schemes resembled “the medieval system of indulgences” when Catholic priests absolved peoples sins for a negotiated fee. The Financial Times (www.ft.com) also reports the findings of its own investigation which uncovered widespread failings in the new markets for greenhouse gases, suggesting some organisations are paying for emissions reductions that do not take place. Many companies are said to be “making big profits from carbon trading for very small expenditure and in some cases for clean-ups that they would have made anyway.”
Methane
Issues: THE SLEEPING GIANT
Methane gas is estimated to be 23 times more potent as a green house gas than carbon dioxide. Although it only lasts in the atmosphere for 12 years, the amount of methane frozen in the permafrost and underwater is vast. As temperatures warm, more methane is bound to be released. The questions are: How much? When? How sudden? Research suggests that methane emissions do not rise gradually, but happen in “burps” as temperature thresholds are breached. Given the massive potential significance of methane in climate change, it receives very little coverage compared to CO2, although, it must be said, coverage appears to be increasing. Since, so much of the methane cycle is out of human control, no overall emissions Goals can be set, nor Actions undertaken, other than keeping overall temperatures down so the permafrost and the underwater methane hydrates do not start “burping”.
Conditions: A SLOW AWAKENING
The huge expanses of water-logged tundra, taiga and lake sediments which stretch across Northern Canada and Russia are considered to be primary sources of methane. As the temperatures rise in the Arctic (which they are reportedly doing at record rates), the danger of a lot more methane being given off by rotting organic matter as the permafrost melts and underwater gas hydrate deposits become “vulnerable”, according to a University of Alaska study. (www.iarc.uaf.edu ).
A Scientific American article states that “Methane concentrations have increased about 150 percent in the air since 1750 and now far exceed the natural range of the past 650,000 years, the U.N.’s climate panel says. And human activities are largely to blame.” Although the rise in methane levels has steadied since 1999, it is thought by scientists to be because the drying out of tropical wetlands seems to canceling out a rise in emissions from other sources.
Other major sources of growing emissions are said to be livestock whose numbers are increasing fast because of the fast growing demand for meat in the newly industrialising world, rice paddies and hydroelectric dams which Brazilian scientists estimate produce enough methane from decomposing organic matter to make them “top contributors” to annual human-caused methane emissions. The study concluded “The massive amounts of methane produced by hydropower reservoirs in the tropics mean that these dams can have a much higher warming impact than even the dirtiest fossil fuel plants generating similar quantities of electricity.” (www.azcentral.com)
A study which suggested that plants produce large quantities of methane is reported in the New Scientist to have been contradicted by the latest research conducted in a “gas tight greenhouse”. (environment.newscientist.com)
Carbon monoxide
Issues: LONG-RANGE CONSEQUENCES
How far do pollutants travel in the atmosphere before dissipating? What are the consequences of long range pollution and poisoning? Only then, what can be done about it?
Conditions: PLUME TRAVELS EAST ACROSS PACIFIC
A European Space Agency survey suggests that one third of “the pall” of carbon dioxide that hovered over Australia during wildfires there in 2004 originated from forest fires in South America. Researchers were characterised as being “very surprised” that a plume of carbon monoxide could travel so far.
Water vapour
Issues: BIGGEST GREEN HOUSE CONTRIBUTOR
Water vapour is the biggest contributor to the “natural greenhouse effect”. The warmer the temperature, the more water vapour is created leading to a positive feedback loop that makes water vapour levels as a key component of climate change. So great is the influence of water vapour in air temperature that some people believe that it is a far greater determining factor in climate change than CO2.
Conditions: THE GREAT UNKNOWN
Although human activities are seen as having little direct impact on global water vapour levels, any role humans have in increasing temperatures will also have the consequence of increasing water vapour levels and the chances of creating a positive feedback loop. For example, as ice melts in the arctic and from glaciers, it is more likely to become water vapour.
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SOURCES
The latest indicator facts and stories were clipped from the most reputable sources using Clipmarks (www.clipmarks.com) during the month of May 2007. Trend Monitor plans to publish a free semi-monthly update compiled from the latest indicators clipped in the previous months.
a) Carbon dioxide
Carbon Emissions Exceed Highest Assumptions Used in Climate Change Studies
Natural sinks – the oceans and plants on land – have been absorbing about half the emissions that humans produce. But the Southern Ocean, which serves as a moat around Antarctica, is losing its ability to take up additional CO2, reports an international team of researchers in the journal Science this week. The team attributes the change to patterns of higher winds, traceable to ozone depletion high above Antarctica, and to global warming.
“There’s been a lot of discussion about whether the scenarios that climate modellers have used to characterize possible futures are biased toward the high end or the low end,” Field adds. “I was surprised to see that the trajectory of emissions since 2000 now looks like it’s running higher than the highest scenarios climate modellers are using.”
If so, it wouldn’t be the first time. Recently published research has shown that Arctic ice is disappearing faster than models have suggested.
Alarming Acceleration In CO2 Emissions Worldwide
Between 2000 and 2004, worldwide CO2 emissions increased at a rate that is over three times the rate during the 1990s-the rate increased from 1.1 % per year during the 1990s to 3.1% per year in the early 2000s.
The research, published in the early on-line edition of the Proceedings of the National Academy of Sciences May 21-25, also found that the accelerating growth rate is largely due to the increasing energy intensity of economic activity (the energy required to produce a unit of gross domestic product) and the carbon intensity of the energy system (the amount of carbon per unit of energy), coupled with increases in population and in per-capita gross domestic product.
The research also shows that the actual global emissions since 2000 grew faster than in the highest of the scenarios developed by the Intergovernmental Panel on Climate Change (IPCC).
“Reducing Emissions From Deforestation” Initiative Launched
Reducing deforestation rates by 50% over the next century will save an average of about half a billion metric tons of carbon every year. This by itself could account for as much as 12% of the total reductions needed from all carbon sources to meet the IPCC target of 450 parts per million of carbon dioxide in the atmosphere by the year 2100.
Tropical deforestation, which releases more than 1.5 billion metric tons of carbon to the atmosphere every year, is a major contributor to global climate change. Recognizing this, a group of forest-rich developing nations have called for a strategy to make forest preservation politically and economically attractive. The result is a two-year initiative, dubbed “Reducing Emissions from Deforestation” (RED), launched by the United Nations Framework Convention on Climate Change
Price placed on limiting global warming
environment.newscientist.com
Stabilising greenhouse gases at a level that would limit global warming to between 2°C and 4°C will cost between 0.2% and 3.0% of annual GDP, says the latest UN report on climate change.
The report says that greenhouse gas emissions grew by more than 70% between 1970 and 2004, largely as a result of the booming energy sector, in which emissions grew 145% during the same period.
How I was deluded by my carbon footprint
www.ft.com
I was expecting praise when I called the carbon reduction guru Chris Goodall. But you know what? Some people will rain on any parade. Mr Goodall said most carbon offsetting schemes resembled “the medieval system of indulgences”, in which corrupt priests absolved sins for haggled fees. According to him, carbon offsetting is bedevilled by problems of validity, double-counting and confusion of aims with poverty alleviation. Paying for offsets “simply allows you to continue driving a car or taking a plane whenever you feel like it”. It distracts us from considering how economies dependent on endless growth could be adapted to reduce pressure on a climate whose limits are proving perilously finite.
I felt good about myself until I spoke to Mr Goodall. Afterwards I felt like an eco criminal who had just wasted 23 quid. I will forget the conversation. Until next week, at least. If I am paying for self-delusion, I want to get my money’s worth.
Industry caught in carbon ‘smokescreen’
Companies and individuals rushing to go green have been spending millions on “carbon credit” projects that yield few if any environmental benefits.
A Financial Times investigation has uncovered widespread failings in the new markets for greenhouse gases, suggesting some organisations are paying for emissions reductions that do not take place.
Others are meanwhile making big profits from carbon trading for very small expenditure and in some cases for clean-ups that they would have made anyway.
Carbon Monoxide
Carbon Monoxide Pollution Over Australia Came From South America
A pall of carbon monoxide that hovered over Australia during wildfires there in 2004 came mainly from forest fires in South America, some 13,000 kilometers (8,000 miles) away, the European Space Agency (ESA) said on Wednesday.
“Even one-third of the carbon monoxide enhancements in North Australia originated from South America.”
The researchers said they were extremely surprised by the finding. Carbon monoxide from forest fires is known to be carried over long distances but is usually detected in dissipated form. The invisible plume travelled eastwards along the southern hemisphere, crossing the South Atlantic, southern Africa and Indian Ocean before petering out in the Pacific.
Methane
Methane in the Arctic and its Role in Global Climate Change
Water-saturated soils and lake sediments are considered the primary sources of CH4 in arctic and sub-arctic landscapes during the summer. It was found that in wet meadow tundra, a 2°C increase in temperature at a depth of 10 to 20 cm in the soil increases CH4 transport, or flux, to the atmosphere by approximately 120%.
Taliks, which lie under lake sediments, are zones of thawed permafrost and are the places where methane originates in winter. Methane accumulates under the ice and is released through cracks and holes. The role of taliks in the current atmospheric CH4 balance could be significantly underestimated.
A very small disturbance of gas hydrates could cause catastrophic consequences within a few decades. Shallow bottom sediment and underlying permafrost have warmed approximately 15°C since the time they originated. The implications of this trend are that shallow off-shore gas hydrate deposits could become vulnerable.
The heat is on for greenhouse gas methane
Methane concentrations have increased about 150 percent in the air since 1750 and now far exceed the natural range of the past 650,000 years, the U.N.’s climate panel says. And human activities are largely to blame.
For the moment, the amount of methane in the atmosphere is steady after leveling off around 1999, said Fraser, leader of the Changing Atmosphere Research Group at Australia’s government-funded Commonwealth Scientific and Industrial Research Organization.
This is thought to be because the drying out of tropical wetlands seems to canceling out a rise in emissions from the oil and gas industry. But how long this lasts is anyone’s guess.
In the United States, cattle emit about 5.5 million tonnes of methane per year into the atmosphere, accounting for 20 percent of U.S. methane emissions, the Environmental Protection Agency says.
What worries Singer most is a rapid release of methane stored in sub-polar permafrost or in huge methane hydrate deposits under the sea. While this has not happened, some scientists suggest it might occur in a warmer world. “If methane hydrates leak, then we’re gone, then it’s over.”
Scientists link world’s big dams to methane and global warming
Brazilian scientists say they have found evidence that the planet’s large dams emit nearly 115 million tons of methane every year, a figure that would put the water-control structures among the top contributors of human-caused greenhouse gases.
Dams don’t seem a likely source of pollutants, but decomposing organic materials in the reservoirs produce methane. Older and larger dams can produce even more of the gas as the materials accumulate in silt.
“The massive amounts of methane produced by hydropower reservoirs in the tropics mean that these dams can have a much higher warming impact than even the dirtiest fossil fuel plants generating similar quantities of electricity,” according to the analysis.
The Brazilian study measured methane emissions from reservoir surfaces, turbines, spillways and rivers immediately downstream from the dams. The study suggests that dams in Brazil and India are responsible for one-fifth of those countries’ total global warming impact.
Hydroelectric power’s dirty secret revealed
The green image of hydro power as a benign alternative to fossil fuels is false, says Éric Duchemin, a consultant for the Intergovernmental Panel on Climate Change (IPCC). “Everyone thinks hydro is very clean, but this is not the case,” he says.
Hydroelectric dams produce significant amounts of carbon dioxide and methane, and in some cases produce more of these greenhouse gases than power plants running on fossil fuels.
This is because large amounts of carbon tied up in trees and other plants are released when the reservoir is initially flooded and the plants rot. Then after this first pulse of decay, plant matter settling on the reservoir’s bottom decomposes without oxygen, resulting in a build-up of dissolved methane. This is released into the atmosphere when water passes through the dam’s turbines.
In effect man-made reservoirs convert carbon dioxide in the atmosphere into methane. This is significant because methane’s effect on global warming is 21 times stronger than carbon dioxide’s.
Plants ‘not to blame’ for potent greenhouse gases
They are off the hook after all. Last year a paper appeared that suggested, to widespread amazement, that plants are major emitters of methane, a powerful greenhouse gas (New Scientist, 14 January 2006, p 13). Now a trial in a gas-tight greenhouse has negated this. Plants do not, it turns out, contribute to climate change by emitting methane.
“The original study might not have allowed enough time for methane in plants’ intercellular spaces to be flushed out”.
Agriculture and climate change
Rice fields emit methane. Large-scale rice farming will increase the volume of methane in the atmosphere. Departments of Agriculture in rice producing countries will have to address and solve this problem singly and collectively.
Water Vapour
Climate Change: Water vapour
Water Vapour is the biggest contributor to the ‘natural greenhouse effect’ and varies the most in the atmosphere. Cold air can hold little water and so the atmosphere over the polar regions contains very little water vapour. In contrast, air over the tropics is very humid and the atmosphere can contain up to 4% water vapour.
It is this ‘positive feedback’ that makes water vapour important in climate change as a small increase in global temperature would lead to a rise in global water vapour levels thus further enhancing the greenhouse effect. Human activities have little impact on the level of water vapour in the atmosphere.
Although human activities have no direct effect on water vapour levels, temperature rises caused by human activity, do have an indirect effect in increasing quantities of water vapour in the atmosphere, thereby increasing global warming.
