Delegates from more than 180 countries began meeting on the Indonesian island of Bali on December 3 at the United Nations Climate Change Conference. The gathering is meant to begin the process of negotiating an agreement on climate change for the period after 2012, when the first commitment period of the Kyoto Protocol expires. But don’t expect swift progress towards an accord that really addresses the world’s climate crisis. The Bali conference will merely begin a drawn-out process of negotiation that is unlikely to conclude before the end of 2009.
Not only will the world’s worst carbon gluttons — including, prominently, the US and Australia — be dragging their feet on emissions cuts: The whole Bali process can be expected to focus on targets that are gravely inadequate.
The discussions over the coming months and years will rest heavily on the Fourth Assessment Report of the United Nations Intergovernmental Panel on Climate Change (IPCC). The final version of this document was released on November 17 as part of the lead-up to the Bali meeting.
Based on the work of some 800 contributing authors and more than 2500 reviewers, the IPCC’s report is supposed to represent the conclusive verdict of the world’s climate experts on questions of global warming. But in the months since initial drafts of the report were published, the document has drawn sharp criticism for its failure to incorporate new research which paints an increasingly grim picture of the dangers ahead.
Using out-of-date evidence, and subject to special-interest pressures, the Bali conference and the negotiations that follow are unlikely to amount to more than “bluewash” — the process through which self-interested actions and policies of wealthy countries are legitimised by being passed through organs of the United Nations.
It would be wrong to suggest that the authors of the IPCC report chose to deliberately mislead the world’s climate-threatened populations. The shortcomings of the document they produced stem to a large degree from the politico-scientific task they evidently set themselves.
In compiling their report, the IPCC’s scientists were clearly determined to banish “climate scepticism” to the realm of crankery, alongside “creation science” and holocaust denial. The new report is much more categorical than its 2001 predecessor in stating that the world is getting hotter, and that human actions are primarily to blame.
Aiming to be completely irrefutable, the authors cited only evidence they regarded as exhaustively proven, and voiced their conclusions in studiously guarded language. The result is a conservative document that, while crushing to the greenhouse deniers, often seems curiously out of touch.
From deniers to foot-draggers
The truth is that it has been some time now since the basic facts of climate change were widely disputed. Even the Bush administration in the US now admits that global warming is real, and that the main cause is the burning of fossil fuels.
The debate has moved on. The key questions now concern the pace and extent of climate change, and the measures needed to combat it. Yesterday’s greenhouse deniers have become today’s foot-draggers.
The new studies that have appeared in recent years have indicated that the processes of climate change are not always linear and incremental, as was often assumed in the past. Instead, it has emerged, gradual human-induced warming is liable to bring natural systems to “tipping points” where numerous positive feedback mechanisms start to operate. Warming then produces further warming, in a self-accelerating spiral.
While a rise of 2ºC above pre-industrial global temperatures is often cited as the point beyond which the danger of runaway global warming becomes acute, certain positive feedbacks appear to be operating already, at a world temperature currently 0.7ºC above pre-industrial levels.
In this increasingly perilous situation, massive, rapid cuts in greenhouse emissions are needed to avoid climate disaster. These cuts will not be cheap, and if the main corporate polluters are forced to pay the price, the impact on their profits will be severe. While formally acknowledging climate change, and even while cultivating a “green” image, capitalist governments and the wealthy elites they represent can be expected to work persistently to thwart changes of the scope required.
The tragedy of the IPCC is that its latest report will do as much to undermine the struggle against global warming as to advance it. On the whole, the report’s conservative findings are rooted in the earlier, “linear” phase of climate change science. At various points, the authors acknowledge that more recent, less rigorously quantified research suggests graver dangers. But instead of being presented as blunt, prominent warnings, these caveats have the quality of afterthoughts.
Meanwhile, it will not be the caveats that form the working data of the Bali negotiators. The latter will focus firmly on the IPCC’s substantive figures, computed on the basis of unrealistic “linear” assumptions.
Albedo flip
The mechanisms now feeding “bluewash” are best illustrated by describing some of the main positive feedbacks threatening the Earth’s climate, and by considering how the IPCC’s report deals with them. First will be the “albedo flip” now underway in polar regions.
As sea ice melts in response to global warming, the dark open water absorbs far more heat from the sun than the earlier ice floes. Temperatures rise, the ice retreats still further, and the cycle repeats itself. The albedo — that is, propensity to reflect the sun’s rays back into space — of huge areas may be transformed within a few decades or even years, with temperatures rising far more dramatically than the general global figure.
This is the process already underway in the Arctic Ocean. Taking into account both geographic extent and thickness, summer Arctic sea ice was recently calculated to have lost more than 80% of its volume in four decades. The effects do not stop at the Arctic coasts. The sharply higher local temperatures also make their effects felt on the Greenland icecap, and in the permafrost regions of Siberia and North America.
On ice sheets such as those of Greenland and West Antarctica, surface meltwater now accumulates during summer. Darker than the surrounding ice, it retains more of the sun’s heat, and steadily melts the ice beneath it. The result in various places has been huge sink-holes into which meltwater cascades in Niagara-like quantities. Forming extensive lakes between the land surface and the ice, the water has the effect of lubricating ice flow. Outcomes already include a doubling of the rate at which two of Greenland’s largest glaciers are dumping ice into the sea.
If all of Greenland’s ice were to slide into the ocean, global sea levels would rise by about seven metres. West Antarctica would add a further five.
Melting on this scale is thought unlikely to occur over less than a millennium. We may be so lucky, but nature has many surprises. As British science writer George Monbiot relates in his book Heat, “In the Antarctic, scientists watched stupefied in 2002 as the Larsen B ice shelf collapsed into the sea”.
What are the forecasts for sea level rises that the IPCC has presented to the Bali negotiators? Global average sea level, the report states, rose by 17 centimetres during the 20th century. For the 21st century, the IPCC predicts rises under various scenarios of between 18 and 59cm.
Then comes the following rider: “Dynamical processes related to ice flow not included in current models but suggested by recent observations could increase the vulnerability of the ice sheets to warming, increasing future sea level rises.”
Might it be cheaper to pay the price of bringing global warming to a halt, rather than to risk allowing large districts of the world’s coastal cities — not to speak of countries such as Holland and Bangladesh — to vanish underwater? Undoubtedly so, but it will not be the prospect of wide-scale inundation that informs the discussions in Bali.
There, the maximum sea level rise that is contemplated will be the one specified by the IPCC: 59cm. Governments around the world will cite this level as scientifically demonstrated, and as endorsed by the UN. Anything higher will be “alarmist”.
Methane
On land in the Arctic regions of western Siberia, temperatures have risen over the past 40 years by some 3ºC, the highest increase observed anywhere on earth. This rise, it appears, is now setting off another positive feedback, this one far more dangerous.
Probably for over 100,000 years, the frozen peat soils of the permafrost areas of western Siberia have held bubbles of the gas methane, produced originally by the rotting of vegetation in oxygen-poor conditions. Though persisting in the atmosphere for only a few decades, methane is a potent greenhouse agent. Over the first 20 years after it is released, its “global warming potential” is 62 times that of carbon dioxide.
The permafrost region of western Siberia is the size of France and Germany combined. In the past few years, the permafrost has begun to melt. From the resulting mud and swamps, methane has started bubbling in large quantities.
In an August 11, 2005, article, the British Guardian cited calculations showing that if the western Siberian permafrost took 100 years to melt, the methane released each year “would effectively double atmospheric levels of the gas, leading to a 10% to 25% increase in global warming”.
Horrifying though this prospect is, the Guardian may have understated it. Last September, a research team from the University of Alaska reported its findings from an extended study of methane emissions from Siberian permafrost. “We show that methane flux from thaw lakes in our study region may be five times greater than previously estimated”, BBC News quoted a team spokesperson as saying.
Astonishingly, the IPCC’s chapter on polar regions devotes only a single brief sentence to methane emissions from permafrost. The phenomenon is not mentioned in the report’s “Summaries for Policymakers”, from which the Bali negotiators will mainly work.
Vanishing sinks
No less threatening than “albedo flip” and the release of methane from Arctic wetlands are the feedbacks that prevent natural systems from absorbing atmospheric carbon at previous rates. As tropical forests grow warmer, they can become susceptible to fire. Burning releases vast quantities of carbon dioxide, raising temperatures still further. Changes in temperature, soils and water availability then often prevent the forests from regenerating. Now savannah scrub and grassland, the former forest areas retain little of their once-huge potential as a “sink” for atmospheric carbon.
When soils become warmer, the metabolism of soil microorganisms speeds up, and soil carbon is oxidised more rapidly. Instead of being a carbon sink, soils become a carbon source. Monbiot notes in Heat that by 2005, decades earlier than expected, soils in England and Wales were emitting more carbon than they took up.
In a warming world, the seas are also less able to absorb carbon. In part, this is for the familiar reason that gases dissolve less readily in warmer water. But now, scientists have pinpointed a further mechanism lowering the ability of the oceans to mop up the carbon spewed out as a result of human activity.
The Southern Ocean was previously one of the Earth’s largest carbon sinks, absorbing about 15% of carbon dioxide emissions. As explained in a May New Scientist article, the gas dissolves into the ocean’s surface waters and is stored at cool depths. But over the past 50 years, rising air temperatures have made the Southern Ocean windier. Increased churning of the ocean now brings cool, carbon-laden water to the surface, where its gas returns to the atmosphere.
As a result, the ability of the Southern Ocean to absorb extra carbon dioxide has dwindled effectively to nothing. Over the past 24 years, the amount of carbon in the Southern Ocean has remained near-constant, even though carbon dioxide emissions have increased over this period by 40%.
According to a British Meteorological Office study quoted by Monbiot, the total capacity of the biosphere to absorb carbon will diminish from 4 billion tonnes a year to 2.7 billion by 2030. That figure, it appears, was calculated before the effective carbon saturation of the Southern Ocean became known.
Targets
As prominent scientists, the authors of the IPCC report are unquestionably aware of the disturbing new studies that are now regularly appearing, and of the urgent note that now pervades climate change debates. Perhaps reluctant to detract from this urgency, the authors do not single out any specific figure from their calculations as an emissions target that the world should strive towards.
Nevertheless, figures that can serve this purpose are to be found in the report. A table buried deep in its pages makes the following predictions: a 30-60% reduction in global carbon dioxide emissions by 2050, relative to 2000 levels, would be likely to result in carbon dioxide-equivalent levels of 490-535 parts per million, and a global average temperature increase above pre-industrial levels of 2.4-2.8ºC.
To people who have followed climate change debates closely, these figures will seem familiar. They correspond to the Australian Labor Party’s “60% reduction by 2050” emissions target, and also to a November 15 European Parliament resolution that is to be submitted to the Bali conference.
But if governments care for their populations, the IPCC’s authors would seem to indicate, they will reject targets such as the above. In a footnote to their table, the authors warn: “The emission reductions to meet a particular stabilization level … might be underestimated due to missing carbon cycle feedbacks.”
In other words, the IPCC scientists admit their figures are primitive, out of date, quite probably too low and, we are left to conclude, potentially dangerous.
Attempts to calculate responsible targets, that take the recent science into account, point to the need for much more stringent cuts. Monbiot argues for a reduction in global carbon emissions of 60% by 2030 — a far more difficult and expensive undertaking. For the most developed countries, he suggests, the cuts by 2030 should be in the region of 90%.
There is no reason to suppose that the targets the Bali conference urges on the world will be based on the up-to-date science. Almost certainly, these targets will be worked out on the basis of the “60 by 2050” formula — endorsed, we will be assured, by the IPCC.
When the final conference resolutions are released, the world may well find itself presented with the makings of a global environmental cataclysm — tied up in sky-blue tape, and stamped with the logo of the United Nations.
From: Comment & Analysis, Green Left Weekly issue #735 12 December 2007.
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