Abrupt climate change has been a growing topic of concern for climate scientists. They fear that global warming could shut down the 'ocean conveyor' that warms the North Atlantic, plunging Europe and parts of North America into Siberia-like conditions within a few decades or even years.
A Pentagon report published this year on the possible social effects – in terms of instability and war – of abrupt climate change riveted public attention. As the Observer put it, 'Climate change over the next 20 years could result in global catastrophe costing millions of lives in wars and natural disasters.'
A natural greenhouse effect is crucial to the earth's atmosphere. As carbon dioxide, methane and other greenhouse gases accumulate in the atmosphere they trap heat that would otherwise radiate off into space. But now, as a result of enhanced greenhouse gas emissions from human production, most notably the burning of fossil fuels, this same greenhouse effect is pushing average global temperatures higher and higher.
Rising sea levels, heat waves, crop failures, worsening floods and droughts, and more extreme weather conditions in general are all to be expected as a result of such increases in average global temperature.
Global warming is expected to be a growing factor in coming decades in species extinction. This rate is higher than at any time since the disappearance of the dinosaurs 65 million years ago. Still, the ruling economic and political interests and their attendant elites tell us not to be worried. Never mind the threats to other species. Human society, we are told, is different.
It can evolve rapidly by economic and technological means and adapt to global warming, which can be viewed as slow, 'gradual' change. Orthodox economists generally caution that we should do nothing that might limit economic growth. Instead they see the only answer as lying in a bigger economy, which will give us more means of addressing problems.
Placing so much faith in economic growth and technological change as answers to global warming is short-sighted. Considerable uncertainty exists as to how far human society can support such 'gradual' climate change. But the problem does not stop there. Scientists are now raising the even more alarming question of abrupt climate change-taking place in years rather than decades or centuries.
Such shifts have occurred before. For example, the period known as the Younger Dryas began 12,700 years ago and lasted 1,300 years, interrupting the warming associated with the end of the last ice age. In the worst of all current, plausible scenarios, such 'abrupt climate change' could occur sometime over the next couple of decades.
Most scientists see these scenarios as highly unlikely. But the shocking Pentagon report, written by Peter Schwartz and Doug Randall, on abrupt climate change took up and dramatised this threat. Schwartz and Randall argue against complacent views of global warming, which suggest that change will be gradual with a limited impact. More frequent droughts, for example, could have disastrous and cumulative effects.
The worst effects from such gradual warming are seen as applying mainly to the poorer countries of the global South rather than the richer countries of the global North-the main sources of carbon dioxide emissions.
This encourages a do-nothing or do-little attitude in the Northern centres of world power. Abrupt climate change alters this picture dramatically. Such change would create catastrophic conditions for human society. Schwartz and Randall look at a scenario of 'thermohaline circulation collapse'.
This would cause a drop in average surface temperature in northern Europe of up to 3.3 degrees Celsius along with severe temperature drops throughout the North Atlantic, lasting about a century. The picture they paint is one of agricultural decline and extreme weather conditions, stretching energy resources throughout the globe.
Well-off populations with ample natural resources and food-producing capabilities, such as the US and Australia, are seen as building 'defensive fortresses' around themselves. These would keep massive waves of would-be immigrants out, while much of the world gyrates toward war.
The report says, 'Violence and disruption stemming from the stresses created by abrupt changes in the climate pose a different type of threat to national security than we are accustomed to today. Military confrontation may be triggered by a desperate need for natural resources such as energy, food and water rather than by conflicts over ideology, religion or national honour.'
For Schwartz and Randall the lesson is clear. Human society must 'prepare for the inevitable effects of abrupt climate change – which will likely come regardless of human activity'.
Since this is a report commissioned by the Pentagon, the emphasis is on how to 'create vulnerability metrics'. These determine which countries are likely to be hit the hardest ecologically, economically and socially, and be propelled in the direction of war.
Such information will make it possible for the US to act in its own security interest. The objective is to safeguard Fortress America at all cost.
Abrupt climate change, though the most dramatic, is not the only outcome possible as a result of global warming. Scientists are even more concerned at present about the potential for 'positive feedbacks' that will greatly amplify global warming.
According to the UN Intergovernmental Panel on Climate Change (IPCC), 'As the carbon dioxide concentration of the atmosphere increases, ocean and land will take up a decreasing fraction of human-generated carbon dioxide emissions.' The hydrological cycle (the cycle of evaporation, rain and runoff that water passes through) could accelerate as a result of global warming, driving temperatures higher faster. Water vapour, the most potent natural greenhouse gas, could trap additional heat increasing the rate at which average surface temperatures rise.
The capacity of both forests and oceans to absorb carbon dioxide could decrease, creating a positive feedback loop that accelerates climate change. Given the level of uncertainty the possibility of surprising developments under these circumstances is very great.
The grim reality is that the more threatening scenarios are becoming increasingly plausible as the data keeps coming in. Carbon dioxide levels in the atmosphere increased at an accelerated level over the past year.
Both the capitalist economy and the world climate are complex, dynamic systems. The uncertainty with respect to climate change and its economic effects has to do with the interaction of these two complex systems.
It is not uncommon for analyses of climate change to assume that the world economy is essentially healthy except for disturbances that could result from the climate. This, however, is an error and underestimates the economic vulnerability of populations and whole societies.
Economic growth is slowing in ways that have deepened the economic crisis for human populations. At the same time, 'nature's economy' is also in trouble, viewed in terms of the diversity of life on the planet. Economic and ecological vulnerabilities are everywhere.
For the Pentagon, the answer to all of these dangers would seem to be straightforward. That is arm to the teeth, prepare for greater threats than ever from thermonuclear war, and build an impregnable wall around the US, closing the masses out.
A more rational response to potential high-impact climate events would be to seek to reorganise society. This would mean moving away from imperatives of accumulation, exploitation and degradation of the natural environment-the 'after me the deluge' philosophy-that lies at the base of most of our global problems. The truth is that addressing the global warming threat to any appreciable degree would require at the very least a chipping away at the base of the capitalist system.
The scientific consensus on global warming suggests that what is needed is a 60 to 80 percent reduction in greenhouse gas emissions below 1990 levels in the next few decades. This is in order to avoid catastrophic environmental effects by the end of this century-if not sooner.
The threatening nature of such reductions for capitalist economies is apparent in the rather hopeless state of the Kyoto Protocol. This required the rich industrial countries to reduce their greenhouse gas emissions by an average of 5.2 percent below 1990 levels by 2008 to 2012.
The US, which had steadily increased its carbon dioxide emissions since 1990 despite its repeated promises to limit its emissions, pulled out of the Kyoto Protocol in 2001 on the grounds that it was too costly.
Yet the Kyoto Protocol was never meant to be anything but the first, small, in itself totally inadequate, step to curtail emissions. The really big cuts were to follow. Even if the Kyoto Protocol were to be enacted this would only open the door to bigger questions.
Will the rich countries of the global North agree to cut their carbon emissions to the extent required? How can the poorer countries of the global South be brought into the climate accord? There would be little opportunity for most of these poor countries – still the victims of imperialism – to develop economically if they were forced to cut back sharply in their average level of greenhouse gas emissions.
The atmosphere cannot support increasing levels of carbon dioxide. Most of its capacity to do so without high levels of global warming has already been taken up by the rich countries. Countries in the global South are likely to be severely constrained in their use of fossil fuels.
Third World countries insist that the North has an ecological debt to the South arising from a history of ecological imperialism. The only way to redress this and to create a just and sustainable climate regime is to base any solution on per person emissions.
Such a position is rooted in the recognition that the US emits 5.6 metric tons of carbon dioxide per person per year. The whole rest of the world outside of the G7 countries (the US, Canada, Germany, Britain, Japan, Italy and France) releases only 0.7 tons of carbon dioxide per person annually.
Inequality of this kind is a major barrier to a smooth climate transition and means that the necessary change must be revolutionary in nature. The only just and sustainable climate regime will be one in which there is a reduction of carbon dioxide emissions to levels that are globally sustainable.
This would be together with a convergence of rich and poor countries around these low, globally sustainable emissions levels. Such safe levels would be less than a tenth of what the North currently emits per person. Obviously, equalisation of per person emissions at low levels for all countries is not something that the US and the other nations in the global North will readily accept.
Yet Third World countries that desperately need development cannot be expected to give up the right to equality in emissions. Any attempt to impose the burdens for global warming on underdeveloped countries in accordance with past imperialistic practices will fail.
To the extent that the US and other advanced capitalist nations promote such a strategy they will only push the world into a state of barbarism, while catastrophically undermining the human relation to the biosphere.
Oceanic Conveyor Belt
1. Warm salty water is drawn from tropical oceans into the North Atlantic. The heat is released, leading to milder winters
2. As it cools, the dense, salty water sinks to the bottom. This draws more water in from the tropical oceans
Thermohaline circulation forms a global ocean conveyor belt, which is driven by differences in temperature and in salt content in the world's oceans. Gradual global warming, which is already taking place, could lead to ice caps melting and to greater flows of fresh water into the oceans. That would dilute the salt content and could lead to the thermohaline circulation breaking down suddenly.
Some scientists believe that this may, in the short term, simply offset the rise in surface temperature brought about by the greenhouse effect. Others think that it could lead to the area around the North Atlantic cooling by 3.3 degrees Celcius in the next two decades, with catastrophic effects.
But the complexity of the environment means that no one knows for sure what will happen if the capitalist system continues to pump out greenhouse gases.
A longer version of this article is published in Monthly Review, May 2004, under the title 'The Pentagon and Climate Change'. John Bellamy Foster's books Marx's Ecology and Ecology Against Capitalism are both available from Bookmarks. Phone 020 7637 1848 or go to » www.bookmarks.uk.com