Category: environment and ecology

Ice Age

The Complete Ice Age: How Climate Change Shaped the World

It might be about the last ice age, but global warming concerns are never far away in Brian Fagan’s latest book The Complete Ice Age: How Climate Change Shaped the World. Fagan collaborates with three other writers to explain how our understanding of the ice age has developed since the great 19th century achievement of its discovery. A book for the general reader, its content is well explained in medium-length chapters with many photographs and helpful illustrations.

Fagan kicks off with an account of how geologists first began to interpret the signs of glaciation and to posit the advance of great continental ice sheets in northern land masses. He also describes the early searches for clues as to when and why the ice age had begun and how many glacial events it may have included, culminating in the essential validity of theories that variations in the motion of the earth around the sun triggered the multiple glaciations.

Paleoclimatologist Mark Maslin takes up the story, first looking at the possible confluence of events, particularly tectonic, which pushed the warm planet of 50 million years ago into increasing coldness. A near ice age 5 million years ago seems to have been aborted by the influence of ocean currents, but full onset was realised some 2.5 million years ago. A climatic rollercoaster followed, with many glacial-interglacial cycles, alternating coldness and warmth. The waxing and waning of the huge continental ice sheets was initiated by changes in the earth’s orbit around the sun which were then amplified and transformed by various feedback mechanisms. Sometimes things happened quickly. The so-called Heinrich events, massive collapses of the North American Laurentide ice sheet, which added enormous quantities of cold fresh water to the North Atlantic and altered ocean currents provide a stark warning of the possible extreme and rapid effects of climate change in the future.

John Hoffecker, an expert on human adaptations to cold climates, offers a fascinating chapter on the human response to the ice age. Novel forms of humankind evolved repeatedly in Africa and migrated into Eurasia during the Ice Age, confronting either intense cold or intervals of warmth. Homo sapiens, finally, with the emergence of mind brought a new capacity for adaptation to environmental challenges. They spread into an astonishing range of habitats and climate zones without differentiating into new species, and displaced their cold-adapted Neanderthal cousins. One hopes that the creative powers of mind will be adequate to the rather different range of challenges ahead.

Paleontologist Hannah O’Regan completes the picture with a survey of the animal life of the ice age. Megafauna survived all glacials but the last, and while acknowledging the controversy surrounding the extinctions O’Regan notes that what differentiates the last glaciation from the others is the arrival of modern humans on all continents.

Fagan returns with a chapter on the way human communities have adapted and flourished in the ten or so millenia since the last glacial period. Sea level rises in the order of 90-120 metres were among the staggering environmental changes initially faced. The relatively stable climatic conditions of the Holocene have seen the development of agriculture and animal domestication and the appearance of civilisation, but even minor temperature and rainfall shifts within this context have had dramatic effects on human societies, especially through the incidence of famine. “We would be rash to assume that our own cities are impregnable to climatic forces that are beyond our control.”  (Readers of Brian Fagan’s absorbing earlier book on the medieval warm period The Great Warming will recall his reconstruction of the devastating effects of drought on many civilisations of the time and his expressed concern that future global warming, unprecedented for human society, will include drought that will severely affect crowded populations in vulnerable parts of today’s world.)

As Mark Maslin reminds us in a final chapter on the future, we are part of the ice age and depend on its legacy. The huge ice sheets of Greenland and Antarctica are witness to that. What happens if you put lots of greenhouse gases into the atmosphere of a planet with lots of ice sheets? That is the experiment which is now under way. What the study of the Ice Age tells us is that when climate changes it can do so suddenly and without warning. The book adds its voice to the many warning us that the experiment is dangerous and should be stopped.

The study of past climates is important for our understanding of the present and the future we are storing up, as a number of books reviewed on Hot Topic make clear, including Broecker’s Fixing Climate, Ward’s Under a Green Sky, Turney’s Ice, Mud and Blood and Archer’s The Long Thaw. But in a book like this one by Fagan and his associates there’s also an intrinsic interest in the picture of the past that is being constructed as the jigsaw is assembled. I read it partly for the sheer pleasure of sensing the past, untroubled, albeit only briefly, by anxieties about the future.

NZ sceptics lie about temp records, try to smear top scientist

homer.jpgThe cranks in the NZ Climate “Science” Coalition have sunk to new lows in a desperate attempt to cash in on the far-right driven furore about the Hadley CRU data theft. Here’s an extract from a press release which was doing the rounds of NZ’s newsrooms this morning:

New Zealand may have its own “Climategate”, including manipulation of temperature readings, according to a combined research project undertaken by members of the Climate Conversation Group and the New Zealand Climate Science Coalition. The researchers claim that temperature readings from seven weather stations throughout New Zealand have been adjusted to show a higher degree of warming than is justified by a study of the original raw data.

The author of the press release and the “research project” into NZ’s long term temperature record is blogger Richard Treadgold, not unknown to readers of Hot Topic. Unfortunately for him, and for the credibility of any of the members of the NZ Climate “Science” Coalition, Treadgold’s approach to the issue is ignorant, his results meaningless, and he can have no excuse for not knowing he was wrong. Worse, Treadgold, Dunleavy and the rest of the NZ CSC seem determined to smear NZ’s best-known and most respected climatologist, Jim Salinger (who did much of the early work on NZ’s temperature record), based on little more than straightforward lies. Their press release continues:

“NIWA’s official graph (done originally by Dr Jim Salinger, who features also in the emails leaked from the Climatic Research Unit of the University of East Anglia) shows considerable warming, which they give as 0.92°C per century, saying this is consistent with global warming over the 20th century. But the actual temperature readings taken from the thermometers show an almost flat trend for 150 years.

These figures all come from NIWA. So, why are they so different from each other? Because NIWA has adjusted the earliest temperature readings downwards by up to 1.3°C, which has the effect of introducing a false warming as the graph then “climbs” to the present day. It’s a disgrace. So far, neither Dr Salinger nor NIWA has revealed why they did this,” said Mr Treadgold.

The real disgrace is that this analysis has been conducted by a team seemingly hell bent on ignoring the facts, preferring instead to make up their own.

Continue reading “NZ sceptics lie about temp records, try to smear top scientist”

Marvellous distempered: the Copenhagen diagnosis

The Copenhagen climate conference (COP15) opens its doors in a little under two weeks. To update participants on the science of climate a new assessment report, The Copenhagen Diagnosis, was released yesterday, and it makes grim reading. Designed to inform “a target readership of policy-makers, stakeholders, the media and the broader public” about the evidence that’s emerged since the 2005 cut-off for the IPCC’s Fourth Report, it is especially strong on the accumulating signs of climate change as it happens.

Evidence of melting of the Greenland and Antarctic ice sheets supports a revision of the expected sea level rise by the end of the century: it “may well exceed” a metre. The rapid sea ice loss in the Arctic in recent years highlights the risks of methane releases from permafrost, but the most direct message is that with global carbon emissions surging up to and beyond the highest of the IPCC’s scenarios, and with pretty strict limits on the amount of carbon we can add to the atmosphere and stay under a 2ºC rise, we need to start cutting emissions soon.

Here’s what the emissions growth looks like:

CopCO2emissions.jpg

And here’s what we need to do to stay under 2ºC:

CopDiagtargets.jpg

It’s a simple enough message. The longer we leave it before starting to cut emissions, the steeper the cuts will need to be. And there’s an obvious corollary: steep cuts will be more expensive. Inaction now means more cost in the future. Where does that leave any government promising to “balance the economy and the environment”?

Below the fold: the full executive summary.

Continue reading “Marvellous distempered: the Copenhagen diagnosis”

Weakened ETS now law

The government’s amendments to the Emissions Trading Scheme became law this afternoon, thanks to support from the Maori Party [Stuff, Herald, Reuters]. Nick Smith called the changes “workable and affordable” and said that they struck “the right balance in protecting the future of our economy and our environment”, but Labour climate spokesman Charles Chauvel was scathing:

It is economically irrational, socially inequitable, environmentally counter-productive and fiscally unsustainable. And its hallmark has been one of poor procedure and hasty consideration.

But what does the new ETS mean for New Zealand’s emissions? The Science Media Centre is collating responses from the science community, and first out of the blocks is VUW associate professor Ralph Chapman:

The passing of today’s Climate Change Response amendment bill through the House is deeply disappointing. Every week, emerging climate science underlines the need for urgent action to cut emissions drastically, with developed countries especially needing to make cuts right now to avoid a global warming drift above 2 degrees, the guardrail against dangerous change. The Government’s amendment bill does way too little to bring down New Zealand’s emissions. The bill has good aspects (e.g. agriculture is included, eventually) but its overall weakness and lack of clarity about its impact on emissions will undermine New Zealand’s reputation and positioning for Copenhagen.

Deeply disappointing. Pretty much my reaction. NZ has now has a much steeper hill to climb in future than was necessary.

Update 28/11: Additional responses from science community, courtesy of the SMC:

Dr Jim Salinger, an Auckland-based climate scientist, comments:

“At present we appear to be bogged down in emission reduction schemes and targets. This thinking is short-term as the high emissions industries in the long run are doomed. We have the low-carbon technology –- which include many forms of renewable energy such as solar electric, solar thermal, wind, wave, tidal, geothermal and bio-energy. All we need to do is scale these technologies up rapidly and harvest the economies of scale.”

Suzie Greenhalgh, Senior economist in the Sustainability & Society team at Landcare Research, comments:

“The passing of the ETS ammendments sends positive signals about New Zealand’s desire to address global climate change, providing greater certainty to business and the population about the path New Zealand will follow. Given that most of the debate so far has been around the risks New Zealand faces with adopting the ETS, now perhaps the debate can switch to where potential opportunities may lie. The inclusion of agriculture, despite its omission in other national schemes, is also an important step for New Zealand’s management of greenhouse gas emissions and may just provide some of these opportunities.”

Associate Professor Euan Mason, of the School of Forestry at the University of Canterbury, comments:

“It is good that New Zealand has begun to address climate change, and if the energy sector is required to surrender credits earned from genuine CO2 sequestration then the ETS should begin to change our behaviour in helpful ways. In its deal with the Maori party the Government implicitly acknowledged that the ETS legislation markedly devalues pre-1990 forest land and that the few credits offered to owners of such land are inadequate compensation. Offering owners of pre-1990 forests the option of replanting elsewhere after land use conversion as an alternative to paying conversion tax would have gone some way to softening the impact on land values. As it stands only a proportion of these land owners have been adequately compensated, and the remainder, both Maori and Pakeha, no doubt feel a sense of injustice.”

Imagining 2020: A Low Carbon Future? Bah! Humbug!

First essay in the new Scoop/Celsias/Hot Topic Imagining 2020 series is a thought-provoking vision from Gareth Morgan and John McCrystal of the Morgan Charitable Foundation:

On the eve of December’s Copenhagen conference on climate, all indications are that there will be no legally binding obligations agreed to by nations insofar as carbon emissions are concerned. The inability of civilisations to pre-empt catastrophe is nothing new: history is littered with instances of societies marching steadfastly to oblivion in full knowledge that this is the consequence of their inability to change. Jared Diamond’s book “Collapse” provides a perceptive and sobering historic collation on this topic.

Our genetic code commits us to paths portending self-destruction, albeit this time the threat is on a scale hitherto not encountered. There is no compelling reason to doubt the view that human activity is causing a rise in the atmospheric concentration of greenhouse gases, and that this in turn will lead a rise in global average temperatures, we can expect the effects of climate change to be making themselves felt in earnest in 2020. And we can probably expect the rise in temperature to be faster than the currently favoured predictions, given that most of the new evidence that emerges daily suggests that the world is warming more and faster than had been expected by those who compiled the IPCC’s Fourth Assessment Report.

So what – if our disposition for denial dictates we adhere to insufficient pre-emptive action – might be the worst of the scenarios we face in 2020? The rate of growth in global emissions of greenhouse gases will have slowed, but it won’t have reversed, as we so badly need it to have done by then. After the debacle at Copenhagen, it will have taken several years for international accord on meaningful reduction targets to be reached. Some nations will have made great strides in reining in their emissions, and some may even have cut them, but New Zealand, like most other liberal democracies (including the United States), will be lagging behind our commitments. The tough decisions that need to be made will have continued to prove just too tough for politicians eyeing their re-election prospects. Centrally planned economies like China, by contrast, and some of the more socialist European states will have taken strong, concerted action. The worldwide search for truly sustainable energy sources will have begun in earnest as stocks of easily obtainable petrochemical resources have become depleted, sending the cost of energy soaring, and this will be the single greatest contributor to the slowdown in the rate of fossil fuel consumption.

New Zealand, like most other liberal democracies (including the United States), will be lagging behind our commitments.

Nevertheless, the world will already be nearing the maximum ‘safe’ limit of 450 parts per million of atmospheric carbon dioxide by 2020, and emissions will not yet have been stabilised, let alone reversed. The conversation both here and abroad will have shifted from what will be necessary to adapt to a rise in the global average temperature of a couple of degrees over pre-industrial levels to what will be necessary in a world that is four or five degrees warmer.

The retention of greater levels of energy within the climate system will have different effects from region to region. New Zealand will be comparatively better off than some places. Next door, for example, Australia will be losing vast areas of formerly arable land to intractable drought, even as the major population centres on the east coast are hammered by powerful tropical storms in the north and torrential rain events in the south. Desertification in Africa and Central Asia will accelerate. Extreme weather events such as flooding, heavier-than-usual and unseasonal snowfalls and heatwaves will afflict Europe. The hurricane-prone regions of the world — the Atlantic seaboard of the Americas, the Pacific Islands, East Asia and the sub-continent — will find themselves cleaning up after more and more intense storms.

In New Zealand, the west coast of both islands will experience increased rainfall, while eastern areas will see precipitation rates dwindle, both the consequence of a more persistently westerly set to the weather. Ironically, our regional average temperature may have cooled over the decade, which would be of considerable comfort to climate change sceptics if only there were any left outside asylums for the chronically deluded by 2020. More powerful weather systems in the Southern Ocean will drag cold air into our latitudes from Antarctica during our winter, making for some pretty grim winters in the south. But increased precipitation and colder winters won’t disguise the change in the distribution of rain and snowfall, and nor will it be any consolation to farmers who are forced to walk off their dusty holdings in North Canterbury, Marlborough, the Wairarapa, Hawkes Bay and the Far North. The competing claims of conservation, agriculture and recreation will be bickering even more bitterly over water use rights in these areas than they presently are.

Ironically, our regional average temperature may have cooled over the decade, which would be of considerable comfort to climate change sceptics if only there were any left outside asylums for the chronically deluded by 2020.

Fox and Franz Josef glaciers will have spent most of the decade advancing, due to higher snowfalls on the western aspect of the Southern Alps. Meanwhile Auckland will have recorded its first case of locally contracted dengue fever.

Higher rainfalls on the Main Divide in the South Island will make water shortages in our hydro lakes something of a rarity, and this will improve our energy security and reduce the quantity of fossil fuels we consume in energy production. The excess electricity in the grid initially released by the long overdue closure of the Rio Tinto aluminium smelter at Tiwai Point will be mostly offset by 2020 through its increased consumption by the burgeoning national fleet of battery electric vehicles. This will work an improvement in the efficiency and the renewable component of the energy consumed by our transport sector, and this in turn will comprise the major component of the slow-down in the rate of New Zealand’s increase in greenhouse gas emissions. Just behind this will be the impact of measures imposed by the government to improve the energy efficiency of domestic and commercial buildings. The third largest contribution will be the carbon offset earned by the re-aforestation of land that was formerly used for agriculture. But agriculture — particularly dairy — will prove resilient: although New Zealand agricultural products will become steadily more expensive on the world market with the addition of a price premium to reflect ‘food miles’, the reduction of demand further afield will be replaced by increased demand from Australia, whose agricultural sector will be under severe pressure.

Like the rest of the developed world, but more like America and less like Europe, we will have failed to wean ourselves off consumption for the sake of it. Everything on the shelves at the Warehouse will be greenwashed in one way or another — wearing a label proclaiming its environmental virtues — but the full range of crap will still be there. The Warehouse’s red sheds will probably have been re-painted green by then, too. But our terms of trade will be desperate, because while we’ll retain our taste for consumer goods manufactured abroad (our domestic manufacturing industry will, of course, have relocated lock, stock and barrel to China, where its largest market lies), demand for our primary produce will barely have survived the imposition of transport tariffs. Tourism will have fallen away markedly, too, as the international conscience turns against air travel as fast as the price of an airline ticket takes off with the addition of carbon levies, and as our claim to the ‘100% Pure’ moral high ground looks sick in light of our failure to act decisively on controlling emissions.

But never mind all that. Housing will be trucking along, as a new generation of Kiwis assembles a portfolio of renters to let to the huddled masses of climate refugees arriving here from the Pacific and from the poorer parts of Asia and the subcontinent. The prices of beef, lamb and seafood will have plummeted as supplying the domestic market becomes more attractive than exporting.

As we happily contemplate our capital gains, we’ll still find it easy to ignore the environmentalists who will be painting doomsday scenarios around the disposal difficulties arising from all the heavy metals used in electric car batteries. Oh yes — and their urging of politicians to set politics aside and take meaningful action on climate change will still be a bemusing sideshow.

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The “Imagining 2020″ Series of articles is a creative commons discussion effort coordinated by Scoop.co.nz , Hot-Topic.co.nz and Celsias.co.nz. Contributions are welcome from all comers. Please see the introduction for an explanation of the project and instructions for how to contribute.