Author: Bryan Walker

Copenhagen 2: dangers ahead

cop_logo_1_r_editedThe second section of the Copenhagen synthesis report, Social and Environmental Disruption, discusses the dangers of climate change relating to society and the environment, noting that scientific research provides a wealth of relevant information which is not receiving the attention one might expect.    

Considerable support has developed for containing the rise in global temperature to a maximum of 2 degrees centigrade above pre-industrial levels, often referred to as the 2 degrees guardrail. The report however indicates that even at temperature rises less than 2 degrees impacts can be significant, though some societies could cope through pro-active adaptation strategies.  Beyond 2 degrees the possibilities for adaptation of societies and ecosystems rapidly decline, with an increasing risk of social disruption through health impacts, water shortages and food insecurity.

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Summing up Copenhagen: what we know now

cop_logo_1_r_edited The synthesis report from the Copenhagen climate congress of scientists held in March has been released. It updates the 2007 IPCC report in the light of the latest developments in the science, and means that the UN Copenhagen conference in December will have an overview of the state of our current understanding of climate change.  

The report has six sections. The first deals with climatic trends and is blunt. Greenhouse gas emissions and many aspects of the climate are already changing near the upper boundary of the IPCC range of projections.  In the case of sea level rise the rate is even greater than indicated by the IPCC projections.  Continue reading “Summing up Copenhagen: what we know now”

“Widespread climate-related impacts are occurring now and are expected to increase”

US Impact report I think I was around eleven years old when I last thought it would be good to be an American.  But I admit to a small twinge of envy as I read the report released yesterday by the Administration:  Global Climate Change Impacts in the United States.  This is a scientific report, backed by the government, telling the general public what is now known of global warming and what it will mean for the US. The sort of thing one would have thought is a core function of democratic government. Meanwhile in New Zealand a select committee is required to solemnly consider submissions from climate science deniers, a PM wants us to be ready in case the science deteriorates and the sceptics are right, and a leading climate scientist is sacked for what sound like trivial offences against management policy.

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Heatstroke

algae

Anthony Barnosky is a Berkeley University paleoecologist deeply concerned about what lies ahead for Earth’s ecological systems if we persist in heating the globe. His recently published book Heatstroke: Nature in an Age of Global Warming explains his concerns. Global warming with its own method of ecosystem demolition has joined the three other factors — habitat loss, introduced species and population growth — by which human activity has impacted badly on ecologies.

Yes, climates have changed in the past and species and ecologies have changed with them.  Many scales of climate change have occurred, from slow tectonic to the fast changes embedded within glacial and inter-glacial times.  Why should an ecologist worry about today’s global warming which is just one more scale? Barnosky has two reasons: one is the rate of change, which is way faster than anything in the past, the other is that the new climate will be hotter than that in which homo sapiens and many other animal species evolved.

Barnosky’s book is packed with examples of what is already happening and what it points to. As the climate warms many species already have to move to survive.  He quotes the result of one survey which showed a set of 99 species of birds, butterflies and alpine herbs which within ten years had shifted on average 6.1 kilometres poleward or 6.1 metres upward in elevation. Dying out on mountain tops is the fate or likely fate of the latter. He traces many other factors, such as the subtle interactions between climate, vegetation, and reproductive success for species such as reindeer, or the change of climate conditions to favour the fungus which kills harlequin frogs – in the tropical mountains of Central America they are now dying in unprecedented numbers because of this new interaction between species. Synchronisations which have served some species well are no longer able to be relied on – marmots in the Colorado Rockies are coming out of hibernation earlier, but heavier snow is taking longer to melt and the green shoots the emaciated marmots need to feed on are not ready. In the ocean he details many instances of marine ecosystems under serious stress from the double whammy of traditional human impacts such as pollution and overfishing now followed by global warming. Corals are a clear example.

Yosemite and Yellowstone National Parks, Kruger Park in Africa and Tambopata Nature Reserve in Peru, are among places Barnosky selects for closer attention. Small mammal species in Yosemite have changed how they live in the park, in a way that indicates some may be on the way out. Amphibians in Yellowstone are in decline. In Kruger between 13 and 20 of the 87 mammal species there today are projected to disappear by 2080. The Tambopata rainforest, along with many rainforests throughout tropical South America, has a 75% chance of being mostly savannah by 2080.

Barnosky devotes a fascinating chapter to what began as his big moment of realisation in a deep cave in the Colorado mountains in 1985. That moment turned into a fifteen year project for four large institutions, more than two dozen scientists and hundreds of volunteers.  They retrieved thousands of fossils deposited over nearly a million years by bushy-tailed wood rats who have the convenient habit of collecting odd objects they find lying around and bring them back to their nests. Among their favourite items are bones, some of them encased in the pellets regurgitated by birds or defecated by carnivores. In the eight feet of excavated layers in that cave was an invaluable record of the changing makeup of local species through the climate changes of the Pleistocene. The story of how the various layers were interpreted and dated is another of those intricate detective operations which mark the scientific interpretation of so many of the clues from the past still embedded in discoverable form.

Barnosky is always considered in his appraisals.  He gives due weight to the resilience of ecologies, and nowhere rushes to judgment. But he thinks we are in a time of accelerated extinction of species, and warns that it could be very large indeed. There were already pressures enough driving us towards dwindling biodiversity.  Global warming increases greatly the speed of the train on its way to mass extinction.

A sober chapter discusses the possibility of climate change acting as a selective force to stimulate the building of new species.  In the past, times of slow climate change seem to correlate with bursts of speciation.  But Barnosky points out that climate change today is at a rate which outpaces mutation rates of most animal and and plant species by a far greater margin than we have ever seen. Recombination within gene pools offers some possibility of evolutionary change, but it is limited without sufficient mutation. At the end of this discussion, engrossing for any lay reader with an interest in evolutionary processes, he concludes: “Global warming is not only doing its part to diminish biodiversity substantially within a century or so, it is also limiting the future evolutionary potential of Earth.”

Barnosky nevertheless insists on hope.  His final chapter centres not only on slowing down global warming but also on a programme for wilderness protection.  First we need to keep what we already have – the 12% of Earth’s surface now protected in some fashion to preserve nature. Second, climate-connection corridors must be provided for species movement. Third, new initiatives are required to minimize high-impact human land use, to create marine-based reserves before it is too late, and to consider the conceptual division of reserves into two functions – one kind devoted to the preservation of individual species and certain assemblages of species, the other devoted to the preservation of wilderness.

The alternative for humanity is the technological “termite-life” of ecological loss.

Barnosky writes with an easy style, combining clarity with a near-conversational level of communication with the reader.  His book offers many insights into the nature of ecological communities and why it is that they matter so deeply.  It is also further evidence if we need it of how profound the effects of anthropogenic global warming are set to be if we do not change our ways.

Disagreeing with Hulme

Why We Disagree About Climate Change: Understanding Controversy, Inaction and Opportunity

Ultimately there’s an opacity in Mike Hulme’s recently published book Why We Disagree About Climate Change.  We are too much engaged with the idea of fighting climate change as a physical reality, he concludes. We are science-saturated but spiritually impoverished. We need to engage with climate change in ways which focus on what we want to achieve for ourselves and humanity.  Climate change is not an environmental problem to be solved so much as an idea which we can use to examine our cultural values and renegotiate our wider social goals about how and why we live on this planet.

Hulme is a climatologist who during the 1990s was actively engaged in the study of climate change, particularly in work on modelling.  He says that he accepts the reality of anthropogenic global warming and that its risks are important and serious.  From 1999 he spent seven years leading the Tyndall Centre, established as an interdisciplinary enterprise where scientists, economists, engineers and social scientists, work together to develop sustainable responses to climate change. He describes this as the time when he began to see that climate change meant very different things to different people, depending on their political, social and cultural settings. The book is largely an exploration of that phenomenon.

Early in the book Hulme seeks to delineate the space legitimately belonging to science and to point to its limits. He specifies three limits in particular. Science always speaks with a conditional voice. Further, when scientific knowledge becomes a public commodity it will have been shaped to some degree by the processes by which it emerges into the social world and through which is subsequently circulates.  Finally, we must not hide behind science when difficult ethical choices are called for. Some of our decisions will be beyond the reach of science.

Applied to climate change it’s not clear to me that any of this affects the core message of the science.  I don’t detect any undue certitude in the scientists I have read.  Uncertainties are usually highlighted, and insufficient knowledge recognised.  Certainly the science can receive some rough and ready treatment when the media fails to convey some of its complexities or hypes up some of the possibilities, but most people who take the subject seriously should be able to make allowance for that. And evading ethical decisions by appealing to the science is an accusation rather too easily made.  If science has been driven to the conclusion that our actions in burning fossil fuel are causing global warming and if some of the possible outcomes are threatening human well-being now and in the future, a fairly immediate ethical imperative surely follows. Much of what Hulme says about the scientific process is unexceptionable, but he presses it harder in relation to climate science than I would have thought current practice requires.  He is, for example, “uncomfortable that climate change is widely reported through the language of catastrophe and imminent peril”. Does this mean he considers there are no catastrophic possibilities associated with climate change?  No imminent peril for those living in low-lying river deltas or islands?  Is he accusing some scientists of overstatement? Or does he regard such a presentation as a distraction from the spiritual challenges which climate change presents and which he considers we are avoiding?  I suspect the last, but he doesn’t really declare himself on what is a fairly crucial point.

Much of the book explores various dimensions of our lives related to human values, human psychology, and political concerns, with a strong focus in each of them on the reasons which make for disagreement over how to respond to climate change. In these chapters Hulme draws on the social sciences and offers interesting enough surveys of the factors which may predispose us to varying responses and disagreements.

The grounds for disagreement are not hard to find.  The hope that many of us cling to is that in the face of the perils of climate change we may be able to transcend those differences and find enough comon cause to lessen the threat posed by anthropogenic global warming.

Hulme holds out little such hope.  He criticises many of the goals which many of us would look to. It’s a comprehensive list. It includes the attempt to establish a universal policy target for greenhouse gases which avoids ‘dangerous’ climate change (his quotation marks); the desire for a single carbon market with worldwide trading; the desire to rethink ideas of consumption, growth and capitalism; the desire to minimise poverty worldwide; the desire to move research and development investment in zero-carbon energy on to a ‘wartime’ footing; the desire to establish a single global policy regime as a means of global climate governance; the promotion of geo-engineering technologies.  In his opinion such goals overestimate the abilities of economics or politics or technology to tame and master our changing climate.

He also criticises the notion that climate change is the overriding project of our generation. George Monbiot is quoted in this context, not with approval: “If we fail in this task, we fail in everything else.”  On the contrary, says Hulme, we should not place ourselves in a fight against climate change as the greatest problem facing humanity, which seeks to trump all others.

So what should we do?  This is the point at which to my mind he dissolves into a kind of spiritual generality.  I have no quarrel with someone who looks for deeper levels of personal engagement with the phenomenon of climate change or seeks a wider outcome than emission reduction, which is admittedly a rather prosaic matter.  But I don’t see why that should rule out our seeking common cause in a common sense attempt to lessen a looming, and yes possibly catastrophic, danger. As  I see it Hulme is exploring a byway.