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Book Review
Abrupt Climate Change: Inevitable Surprises
Ocean Studies Board, Polar Research Board, Board on Atmospheric Sciences and Climate
ISBN: 978-0-309074-34-6 2002 244 pages National Academies Press
Gavan McDonell
Visiting Professor, Sustainability Studies, University of New South Wales, Sydney NSW
On 22 February 2004, much of the world's press had a new plaything. The London Observer ran a headline, 'Now the Pentagon Tells Bush: Climate Change Will Destroy Us'. European papers picked it up. One US paper blared, 'Pentagon Warning of a New Ice Age'. Soon the Pentagon backed off from, though did not withdraw. It hardly could, because, as outlined below, the claims were underlain by recognized scientific evidence.
The cause was of the flurry was the slender report listed first above (www.ems.org/climate/pentagon_climate_change.html), and the evidence is summarized in the major report listed second above, (http://books.nap.edu/0309074347/html/1.html). Both should be on the priority reading list of government and corporate planners, policy developers, strategic analysts and all those concerned with sustainability and innovation.
The first publication was commissioned by Andrew Marshall, a senior, long-term and influential Pentagon adviser. Prepared by two highly credentialed business strategists, Peter Schwarz and Doug Randall, it reviews evidence both from history, on the incidence of sudden shifts in climate, and from recent times, on the possibility that conditions are developing which could precipitate such changes. Increasing numbers of business leaders, economists, policy makers and politicians are concerned about the impacts are working to limit human influences on the climate (P Schwarz & D Randall 2003). But, these efforts may not be sufficient or be implemented soon enough. Schwartz, a former employee of SRI International in Menlo Park, once ran scenario planning for Royal Dutch/Shell in London. Royal Dutch/Shell was long regarded as one of the leading corporate practitioners of long term and scenario planning. Randall was a former senior research fellow at the Wharton School in Pennsylvania.
The analysis covered a range of effects that could impact upon global and regional climates and human economic, social and security relationships. They used well established, but necessarily frail, methods of scenario development - frail, given that the modeling both of such climatic events and of their impacts is poorly understood. The impacts which they analyzed included food shortages, decreased availability and quality of fresh water in key regions, disrupted access to energy supplies and their implications.
The following graphic from the Report shows how abrupt climate change may cause human carrying capacity to fall below usage of the eco-system, suggesting insufficient resources leading to a contraction of the population through war, disease, and famine.
From: Peter Schwarz and Doug Randall (2003)
The report stressed that different regions of the globe would be affected differently. Northern areas, such as Europe, China and North America, would be hit hardest, with temperature drops of up to 5 degrees Fahrenheit. Temperature rises of up to 4 degrees would occur throughout Australia, South America and southern Africa. There would be widespread drought in critical agricultural regions, and intense winter storms and winds. All of this would generate national and international security issues, the main focus of the report, with contingent challenges to social and institutional governance.
Many point to technological innovation and adaptive behavior as a means for managing the global ecosystem. Indeed it has been technological progress that has increased carrying capacity over time. Over centuries we have learned how to produce more food, energy and access more water. But will the potential of new technologies be sufficient when a crisis like the one outlined in this scenario hits? P Schwarz & D Randall 2003
This document was not, in fact, merely a matter of hype, as the world press seemed to treat it, but rested on solid scientific concerns which have been around for some time.
These are set out in the above major book on the abrupt change scenario, published by no less than the combined US National Academies (Washington DC 2002):
Recent scientific evidence shows that major and widespread climate changes have occurred with startling speed. For example, roughly half the North Atlantic warming since the last ice age was achieved in only a decade, and it was accompanied by significant climatic changes across most of the globe...Abrupt climate changes were especially common when the climate system was being forced to change most rapidly. Thus, greenhouse warming and other human alterations of the earth system may increase the possibility of large, abrupt, and unwelcome regional or global climatic events...future abrupt changes cannot be predicted with confidence, and climate surprises are to be expected (italics added)...The new paradigm of an abruptly changing climatic system has been well established by research over the last decade...but ...is little known to ...scientists and policymakers. Executive Summary
What would be the mechanism of the 'climate surprises'? The global balance of heat exchange which sets our climates is maintained by the flow of inter-related ocean currents, the so-called 'Ocean Conveyor'. Cold, salty, heavy waters in the North Atlantic, fed by melting floes and glaciers from around Greenland and beyond, slide downwards as they stream southwest, forming a current which moves past the Americas, and then eastwards below the African coast. It continues east, passing between Australia and the Antarctic, to sweep first north, towards China, and then north east and parallel to the Bering Strait. The cold waters push up and ahead the warm, lighter Pacific and equatorial waters, and the current rises to the surface near Alaska. Then, now formed of warm waters, it flows south west above Australia, around below Africa, northeast towards Canada and thence again to the North Atlantic where the heat transfer process continues.
What is the nature of the present concern? Firstly, evidence from Greenland ice cores has shown that drastic climate changes, resulting from the stalling of the Conveyor, have taken place in the past within as little as 10-15 years. Secondly, if the North Atlantic grew fresher as a result of enlarged outflows from the northern fiords and oceans, density changes could halt the gravity feed of the Conveyor. Freshening was detected some decades ago. Recent research indicates that it has become substantial and is thought to be associated with accelerated melting of the northern ice resulting from global warming. The Pentagon report (October 2003) cites two articles in Nature - in 2001 and 2002 - suggesting that the North Atlantic salinity level may lower, increasing the likelihood of a collapse of the Ocean Conveyor. Signs of a possible slowdown include evidence that the flow of cold, dense water from the Norwegian and Greenland Seas into the North Atlantic has dropped by at least 20 percent since 1950.
That such changes would produce many large and interrelated economic and social consequences is apparent. These would then trigger the Pentagon's worry-regional and global instabilities. Optimists assert that the benefits from technological innovation will be able to outpace the negative effects of climate change (P Schwarz & D Randall 2003). Policy makers have always relied on the simple, relatively comforting and always unlikely gradualist scenario of uniform temperature change arising from greenhouse warming. Nature abhors straight lines, convenient though they are to computer analysis. The deeply complex processes of climatic and associated regional change and of the associated human, economic, institutional and corporate effects generate many imponderables and immeasurables.
Our leaders and the media have been aware of the hazard for at least a year. In an important address to a panel on abrupt climate change at the influential Davos World Economic Forum in January 2003, Robert Gagosian, president of the authoritative Woods Hole Oceanographic Institution, succinctly outlined the processes, the evidence, and the urgent priority of developing the knowledge needed for good forecasting models (www.whoi.edu/institutes/occi/currenttopics/climatechange_wef.html).
' ...we do not,' Gagosian says, 'have a system in place for monitoring slower-developing, but critical, ocean circulation changes...The debate on global change has largely failed to factor in the inherently chaotic, sensitively balanced, and threshold-laden nature of Earth's climate system and the increased likelihood of abrupt climate change...the region most affected by a shutdown-the countries bordering the North Atlantic-is also one of the world's most developed...A first step (to reducing uncertainty) is to establish the oceanic equivalent of our land-based meteorological instrument network....Considerably more research is also required ...about complex ocean-air processes that induced rapid climate changes in the past, and thus how our climate system may behave in the future.'
Government, corporate economic and social strategists should consider Gagosian's words carefully. Remember when everyone thought that climate change was just a boffin's blip? Ten or fifteen years ago? And now?
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