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Posts Tagged glaciers

Messages from a sizzling continent: Salinger on the Aussie heatwave Gareth Renowden Jan 20

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This op-ed by climate scientist Jim Salinger first appeared in print editions of the New Zealand Herald last Tuesday.

Global warming is not a phenomenon for future generations to deal with: it has arrived. And more frequent heat waves and climate extremes are part of this phenomenon. As I watch from my summer roost in northern New South Wales, the somewhat unprecedented heat is searing the Australian continent making it tinder dry with fires springing up everywhere. These raise some pertinent lessons on climate and risk management for New Zealand.

Firstly let’s look at some figures and ask the question of what are the climate mechanisms behind the heat waves.

Incessant heat has struck the interior with daytime highs soaring to the high forties. As I pen this on Saturday 12 January the mercury rose to 49.6ºC at Moomba, just shy of the all-time Australia record of 50.7ºC recorded at Oodnadatta in 1972. The national average maximum temperature (the average daytime maximum temperature for the entire Australian continent); which in this case is gauging the areal extent of the heat, jumped back up to 39.2ºC on Friday  — making 8 days above 39ºC this year and 11 days straight above 38ºC. The temperatures since 2 January are 39.21, 39.55, 39.31, 39.71, 40.33, 40.11, 38.36, 38.65, and 39.20ºC.

There have been locations in Australia (not the same location, somewhere over an area of thousands of square kms) that posted a temperature in excess of 47.7ºC since the 2nd of Jan. A temperature in excess of 48ºC was posted on 7 of those days. As a comparison the highest global temperature recorded is 56.7 C recorded in Death Valley, California in 1932. During that event dead birds rained out of the sky at Furnace Creek.

For New Zealand, the messages from the climate system of global warming are far more subtle. This is because we are immersed in an oceanic environment. Our clearest signal is seen in night time temperatures. Over the period 1941 – 2011 the number of days with temperatures less than 0 deg C has decreased from 11 to 4 per annum at measured North Island locations, and 35 to 23 days a year in the South Island. And the lowest night temperature in any one year has increased from -2 to -1ºC in the North Island and -4.8 to -4.3ºC in the South Island over this 70 year period.

More tellingly has been the fate of the permanent ice that makes Aotearoa ‘The land of the long white cloud’. This has shrunk dramatically from over 100 cubic kilometres (km3) clothing our Southern Alps around 1900 to 45 km3 in 2008. Allowing for the 3 deg C warming projection (Dr James Renwick, New Zealand Herald, 10 January) this ice mantle would diminish to a mere 15 km3 if its former glory!

New Zealand is now lagging well behind our Pacific neighbours in taking action to diminish carbon emissions to the atmosphere. On 1 July 2012 Australia took a very bold step and introduced a A$23-a-tonne price on carbon emissions which directly affects 294 electricity generators and other companies. The federal Government is aiming to cut carbon emissions by 5 per cent by 2020, with the carbon tax shifting to an emissions trading scheme in 2015.

And on 24 November 2012 California issued the USA’s first broad-based cap-and-trade blueprint to reduce greenhouse emissions. The pioneering effort caps greenhouse gases emitted by more than 600 power plants, refineries, cement plants and other big factories at 15 percent below today’s levels by 2020. And although the Obama administration may not be able to ratify Kyoto through Congress, carbon dioxide has now been ruled a pollutant by the U.S Supreme Court. As such carbon dioxide emissions can be regulated by executive order of the president.

The current National Government has been rapidly back pedalling from the robust emissions trading scheme (ETS) introduced by the former government. It has progressively gutted the ETS to what Herald columnist Brian Farrow described as an already pretty aqueous ETS. It has also opted out of the 2nd Kyoto Protocol period committing to legally binding emissions reduction target until 2020. This earned New Zealand several “Fossil of the Day” awards at the international climate talks in Doha, Qatar, December 2012.

The climate system is now speaking louder. Global warming is now becoming very serious and is already impacting on life and property. It is here, now and not a phenomenon for future generations to deal with. New Zealand must step up to the plate and embark on a course of emissions reductions targets as soon as possible, to claw back rapidly rising greenhouse gas levels in the atmosphere. If we do not act now the severity of such heat waves, other climate extremes and sea level rise impacts and the subsequent damage to life and property will increase. There is no time like the present to invest in our future wellbeing.

Bad news but great pictures: dating NZ’s shrinking glaciers shows strong link between ice loss and CO2 increases Gareth Renowden Sep 13

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Here’s a superb video from the Department of Education at the American Museum of Natural History, showing how NZ and US scientists are examining the precise timing of glacier advances and retreats in the Mackenzie country around Lake Pukaki using surface exposure dating. Like all good geologists they use big hammers and small explosives to shatter rocks in order to sample “cosmogenic” Be-10 — a beryllium isotope formed when cosmic rays hit quartz in newly exposed rocks. See here for more on recent surface exposure dating work in the Pukaki area. Hat tip to Climate Crocks for spotting the video.

Greenland’s extraordinary summer: melting records and ice island setting sail Gareth Renowden Jul 26

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July has been an amazing month in Greenland. The Petermann Glacier has given birth to another huge ice island — taking its terminus further back up its fjord than at any time in the last 100 years (at least), record high temperatures have been recorded at the summit of the ice sheet at 3,200 meters, initiating surface melt over the whole vast sheet, ice sheet albedo has plummeted, and the Jakobshavn Isbrae’s calving front has retreated into the ice sheet.

The best coverage of the Petermann event, as on most matters to do with the Arctic summer and sea ice melting season is to be found at Neven’s Arctic Sea Ice blog. It’s well worth reading the comments under the Petermann post there, to get a really informative picture of what’s being going on. Here’s a description by Dr Andreas Muenchow1 of what the calving would have been like:

I described the Petermann calving to some media folks as a gentle and very quiet affair similar to a rubber duckie pushed out to sea from the deck of a flat pool.

Some duckie, some pool…

Illulisatanimated2012203Further south, the the “root” of the Jakobshavn Isbrae has enlarged significantly, with the calving front of Greenland’s most productive glacier retreating further into the ice sheet. The “blink” image I’ve cobbled together (left) shows day 203 of this year compared with day 202 of last year2. The difference is large and very obvious. Greenland specialist Dr Jason Box was flying out of Ilulisat shortly after the retreat earlier this month, and snapped the photo below out of the window of his plane. As he commented on Facebook, it looks like the glacier has divided into two streams.

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Up at the summit of the Greenland ice sheet at 3,200 metres, a new high temperature record of 3.6ºC was set on July 16, hard on the heels of four days in row of temperatures above freezing, from July 11 to 14. Considering that temperatures above zero had only been recorded four times in the preceding 12 years, this amounted a remarkable heatwave, and triggered an astonishing melt record.

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This NASA graphic shows how the melting surface, shown in shades of red, spread over the whole surface of the ice sheet from July 8 to July 12. This amounts to “the largest extent of surface melting observed in three decades of satellite observations”, according to NASA. The last such melting event occurred in 1889, and ice cores show that they occur every 150 to 250 years. However, given the steady increase in melt area over the last decade, and the precipitous drop in ice sheet albedo (see below), especially at high altitudes, it may not be 150 years before such a melt happens again.

GISalbedo201207

The last time I looked at this extraordinary summer in Greenland, it was to report Jason Box‘s view that “it is reasonable to expect 100% melt area over the ice sheet within another similar decade of warming”. It took two weeks to come true. Forgive me if I find that alarming.

  1. Andreas provides great coverage of the Petermann glacier at his blog — perhaps unsurprisingly, as he’s on his way up there to recover instrumentation soon.
  2. Source: 2012, 2011.

Jim Renwick on the state of climate science Bryan Walker Jul 24

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I have been listening to a lecture by Victoria University climate scientist, James Renwick, who has recently moved to the university from his post as principal climate scientist at NIWA.  In the seminar he sets out in broad terms some of the latest developments in the science. It’s a very clear summation, with some recent interesting graphs and charts, showing the direction which in which climate change is continuing to move. Needless to say there’s no change in direction apparent. I recommend the lecture as well worth listening to. I’ll only touch lightly in this post on the scientific content of the lecture; my main purpose is to highlight comments Renwick made along the way indicating the concern he feels about where we are headed.

I was particularly struck by an early statement made after he had remarked on the 2011 emissions reaching a record level of 31.6Gt and pointed to the graph of steadily increasing concentration of CO2 measured at Mauna Loa. I’ve transcribed it:

I feel a kind of morbid fascination with this stuff. It’s a really fascinating science issue – and I’m really  interested to  find out what’s going to happen to the climate and how much ice is going to melt and what’s the temperature in 2020 going to be and all the rest of it.  It’s intriguing, it’s my bread and butter but you know what I feel is – I look at this and say jeez we’re really doing this, we’re doing this experiment, we’re really playing this game with the Earth, we’re gambling with millions of lives and I sort of feel disgusted with myself that I find it interesting from a scientific point of view   It’s certainly interesting, but it’s more than interesting — it’s a very dangerous game we’re playing.

Just how dangerous becomes all too apparent as he proceeds. Global temperatures are continuing their steady increase from since around 1970. Sea levels are steadily rising, with the NZ rise similar to the current global mean of 3 mm per annum, roughly double that of the early 20 century. There’s an interesting comment on the temporary drop in sea level rise in 2010 and 2011 considered due partly to the La Niña event but also probably partly to the transfer of water in heavy rains, which he identifies as one of the new things around understanding sea level rise.

Ice is continuing to melt both in glaciers and in the Greenland and Antarctic ice sheets. Information about the ice sheets is improving considerably, including the mapping of ice movement. We don’t know enough yet to understand all the implications for sea level rise, but we’re getting there. He refers to a recent paper suggesting that we may be only a degree or so away from the temperature rise which could get the Greenland ice sheet moving irreversibly. The decline in Arctic sea ice in both the extent and the age of ice he describes as “fascinating in a bad kind of way”.

Renwick points to research suggesting that if we can halve emissions by 2050 then there’s more than a 50% chance of “staying below that 2 degree warming line which everyone appears to think, at a policy level at least, is a good thing to do”. He doesn’t explicitly say so but that two degree boundary is hardly established as safe by any science I have seen, and perhaps the terms in which he characterises the warming line are indicative of that. In any case as the lecture proceeds he recognises the possibility that we might be looking at a 4 degree rather than a 2 degree rise.

On rainfall attribution Renwick notes that model trends in all latitude bands are proving much weaker than observed trends. So things are changing in the direction we might expect but they’re actually changing faster than the models might tell us.

After covering such matters as the widening of the tropical belt by about 3 degrees latitude since 1980, the contraction of the Southern Annular Mode (the westerlies) toward the pole and the likelihood that 1 in 20-year warm periods are likely to become 1 in 2 years, Renwick moves to the implications for political action in the light of the fact that 2 degrees of warming is now virtually certain and that in fact we might be looking at more like 4 degrees:

“…which is extremely risky – large changes to the climate system, large changes to where the rain falls and how much, and food production and sea level rise.  Big stakes I must say, but some massive opportunities to do something good and to even make money if you can come up with some clean and green ideas that will sell.  But to me there still isn’t really the political leadership there to actually make things happen, which is quite concerning… We don’t have a conception of intergenerational debt, stewardship and all that kind of thing …We’re borrowing the earth against future generations and the earth is staring to bite back.”

I listened to the lecture mainly for its interesting presentation of the advances in the scientific understanding of climate change in the years since the last IPCC report, but the two extracts I’ve transcribed are also valuable for the way they communicate the human concern that accompanies the science. It’s not delivered in ringing tones, but it’s recognisable and surely appropriate. Moreover Renwick is voicing a level of disquiet widespread among climate scientists.

What is unfolding is deeply threatening to human life and the failure to address it adequately at the political level raises disturbing questions about our capacity to act ethically as societies. For climate change is at base now an ethical question. It is to do with the way our actions impact on the lives of others both now and in generations to come. And remedial action is not beyond our control. The ball is in the policy makers’ court. We should keep insisting that they address the issue adequately and with full seriousness.

Cambridge on ice Gareth Renowden Mar 17

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From Cambridge University: the director of the Scott Polar Research Centre, Prof Julian Dowdeswell talks about his job. He has to visit Greenland and Antarctica to measure glaciers, so there are lots of pretty pictures to watch. Not a bad job, even if the implications of what he’s finding (Greenland outlet glaciers doubling in speed) are worrying…

Peruvian glacier melt challenges US security Bryan Walker Jan 19

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The melting glaciers of Peru have figured in previous Hot Topic posts such as the review of Mark Carey’s book In the Shadow of Melting Glacier and the report from Guardian journalist John Vidal’s Oxfam-sponsored Andean tour. I was therefore interested to come across an article on what the loss of the Peruvian glaciers implies for US national security. Not that the national security of America normally figures on my list of concerns about what climate change is doing to Peru, but I’m happy to add it if it is required to awaken more widespread US awareness of the realities of climate change. The fact that a version of the article appeared in last weekend’s Washington Post was testimony to that potential. US national security concern might also represent Peru’s best chance of getting much-needed assistance in the enormous adaptation measures facing them.

Heather Somerville, the article’s author, is a member of a team of graduate journalist students from Medill School of Journalism who have been investigating the effects of climate change on US national security in various parts of the world.

Said a former CIA Director:

’Think what it would be like if the Andes glaciers were gone and we had millions and millions of hungry and thirsty Southern neighbours. It would not be an easy thing to deal with.’

Somerville summarises the effects already under way in Peru:

’…glacier melt has begun to deplete crops, displace communities, cause widespread drinking water shortages, destabilize hydroelectric power, diminish trade and affect transportation and tourism. The trend is expected to cause regional conflict, economic crises, increased crime, broken infrastructure and food insecurity.’

Without substantial foreign assistance within the next five years the climate change advisor at Peru’s Ministry of Foreign Affairs sees the shrinking of the glaciers leading to a social and economic disaster.

If the US does offer assistance it is likely to be bound up with strategic questions.

’[The Obama administration] must decide whether to send money, development assistance and possibly even military help south to an important democratic ally on a continent where Chinese and Iranian influence is growing, and anti-U.S. sentiment permeates certain regimes.

’Other U.S. allies vulnerable to the impacts of climate change will be paying close attention to how the U.S. responds. Peru’s crisis could set a precedent for how the U.S. uses diplomacy, foreign aid and the military to address the climate change threats around the world.’

The State Department is taking an active interest in the impacts of climate change on the region, acknowledging it as a significant threat which the US must come to terms with in respect to the security challenges it poses. Some assistance has been forthcoming from Washington but the article reports frustration from Peruvian officials with what they see as poor coordination among US agencies, US disregard for the importance of global cooperation and an agenda that fails to address the urgent need in Peru.

Somerville makes it clear that the need is urgent. And it is by no means limited to the areas adjacent to the glaciers, serious though it is for them.

’Life on Peru’s coast depends on water from the Andes. Most of its agriculture production is on the arid coast, fed by water from the Andes. Glacier-fed rivers also support the nation’s largest hydroelectric plants, which provide 60 percent of the country’s electricity.

’Lima, the world’s second largest desert city, is almost totally dependent on Andean rivers fed by glacier melt. Water shortages are widespread there, and even worse in communities nearby that can’t compete with the capital for meagre water supplies.’

The Pentagon’s Southern Command (SouthCom), responsible for Latin America, has also been looking at the security aspects of climate change in Peru.  Their environmental security expert comments that there is some way to go to get a complete buy-in from the Department of Defense that this is a core military role, but Somerville comments that SouthCom probably won’t have a choice but to start planning for climate change. One of SouthCom’s primary missions is humanitarian aid and it has a history of being called on for disaster response in Latin America.

Not that Peru is sitting helplessly waiting for outside assistance. Somerville reports that it created a national strategy on climate change in 2003 and in 2008 set up a Ministry of Environment with oversight of climate change programmes. Work is being undertaken in conjunction with the US Agency for International Development and non-profit organisations to build water reservoirs in Andean communities and monitor water flow from the glaciers.

But resources are lacking, and the Peruvian Ministry of Foreign Affairs is asking Washington and other allies for at least $350 million every year through 2030 for reservoirs to collect runoff, dams to regulate water flow from the Andes and irrigation techniques. Said a spokesperson:

’If we don’t solve our problems … this will become a problem for the United States. When you have a dysfunctional country, you have a problem for the entire region.’

Whether national security concerns will drive significant aid for countries like Peru remains to be seen. But the concerns are clearly making some think seriously about what climate change is doing to the world. I found myself wondering about how this is going down with the climate change deniers so prominent among Republicans in the House. Presumably if climate change is not happening it can’t be posing a security threat to the US.  But what if you’re a politician who professes great concern about national security?  And what if that question comes close to home as it does in some of the other articles in the series to which Somerville’s belongs?  There’s an article on the threat to Houston. Another on the what sea level rise will do to military bases on the US coast. Another on the threat of climate change-related disease in the US as well as other countries.

A day must eventually dawn when denial becomes impossible to maintain even when it is bolstered by wealthy vested interests. If perceived national security threats will help bring about that day, then the more they are pointed out the better.

Moving the earth for oil Bryan Walker Jan 11

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Ethical oil. That’s what Canada is producing from its massive tar sands operation, according to the newly appointed Environment Minister Peter Kent. I admit to having missed that dimension in what I have read of the oil extraction from tar sands. I understood that when the CO2 emissions from its production is added to the CO2 from its combustion it emits between 10 and 45 percent more than conventional crude. I also understood that the environmental effects of the mining and extraction process are appalling, that restoration undertakings are more promised than real and that First Nation communities are gravely affected. Most telling of all I understood that according to James Hansen if the world wants to have a chance of avoiding dangerous climate change it must not only rapidly phase out coal emissions but also leave unconventional fossil fuels such as oil from tar sands in the ground.

But I didn’t understand that tar sand oil was ethical. What makes it so? The Minister explains:

’It is a regulated product in an energy superpower democracy. The profits from this oil are not used in undemocratic or unethical ways. The proceeds are used to better society in the great Canadian democracy. The wealth generated is shared with Canadians, with investors.’

He added in a subsequent interview that the Obama administration needs to be reminded that, unlike the energy it buys from other foreign suppliers, oil-sands petroleum ’is the product of a natural resource whose revenues don’t go to fund terrorism.’

So the oil is ethical because Canada is a democracy. He doesn’t actually name the countries which produce less than ethical oil, but his characterisation presumably draws on a recent book Ethical Oil by Canadian author Ezra Levant which instances Saudi Arabia, Iran, Nigeria, Venezuela and Sudan as much less desirable sources.

As the Globe and Mail sees it, Kent’s pitch is ’an attempt to beat back efforts by U.S. politicians and activists who want a boycott of Canada’s oil sands owing to its greenhouse-gas-heavy extraction methods and ensuing environmental damage’.

Kent complains that the product has been demonised, but in its support falls back on the sort of argument we’ve heard a lot of in New Zealand. He calls it ’relevant measurements’.

’Oil-sands production accounts, I think, for 5 per cent of Canada’s total greenhouse-gas emissions. It’s less than one-tenth of 1 per cent of global greenhouse-gas emissions and barely 1 per cent of the equivalent greenhouse-gas emissions by American coal-fired power generators.’

Citing the tentative economic recovery, Kent said the Harper government will not impose any greenhouse-gas reductions on the oil patch that would discourage investment across the sector.

’Our focus for the next several years is going to continue to be on maintaining the economic recovery and we will do nothing in the short term which would unnecessarily compromise or threaten to compromise that recovery. It is not our intention to discourage development of one of our great natural resources. We know it can be developed responsibly.’

The Canadian government does have some intentions for emissions reductions — 17 percent down from 2005 levels by 2020. But the rules when they come will be drawn up ’with a sensitivity to maintaining a competitive situation’.

It is clear that the Canadian Government has not faced up to the fact that we can’t both successfully tackle the threat of climate change and also pursue fossil fuels to depletion. That’s the plain fact of the matter, and no amount of bluster about developing natural resources or economic recovery or maintaining competitiveness can alter it.

It’s a fact which many Governments must face, not only Canada’s. Indeed while reading the Globe and Mail report I was struck by the similarities to the position of the New Zealand government. Our Minister of Energy and Economic Development is defending the exploitation of what he describes as our natural resources with equal robustness. He paints a rosy economic future from deep sea oil drilling and lignite coal development. It will, of course, be undertaken with due regard for the environment. In fact, he went so far as to say in his opening address to the NZ Petroleum Conference last September that the development is needed to enable us to care for our environment.

’I would strongly argue that it is only through a strong economy that New Zealand can afford the expenditure required to look after and improve our environment. A strong economy allows the government to spend money on biodiversity, on improving water quality, on insulating our houses, on protecting our endangered species and preserving our heritage. All those things cost money. None of them are free. A strong economy allows expenditure on them…

’So rather than stop ourselves from using our natural wealth, this government has made it clear we want to develop our natural resources in an environmentally responsible way.’

The doublethink is staggering.  The only honest way of putting what both Ministers are saying is that anything we do towards emissions reduction will be token at best, because we are dead set on developing our fossil fuel resources. Why don’t they just put it baldly so that we all know where our Governments stand?  Why the weasel words about environmental protection?  Why talk of reducing emissions when they plan fuelling their increase on a large scale?

We work as rapidly and purposefully as we can to reduce emissions or we make the future climate changes even worse than they already will be.

No doubt I’ll be accused of being simplistic in pressing such questions when the issue is one of great complexity. Well, there may be complexities to be worked through, but the underlying picture is starkly simple. We work as rapidly and purposefully as we can to reduce emissions or we make the future climate changes even worse than they already will be. It was a group of Canadian scientists who have just published a widely reported paper in Nature Geoscience which predicts climate change resulting from even the present level of CO2 will be persisting for centuries. I wonder what Canadian Ministers make of that.

Another newly published Canadian paper was reported on TV3 news last night because of the major shrinkage it predicted in New Zealand glaciers during this century. I wonder if that registered with New Zealand Ministers. All the wealth of the South Island lignite fields or of oil discovered in deep sea drilling won’t suffice to put the ice back in the glaciers.

Albert the knowledge penguin on climate Gareth Renowden Jan 03

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Albert the Knowledge Penguin explains the real story of climate change, from the science to the politics, and gets it right. Read the rest of the story here. British cartoonist Darryl Cunningham has clearly done a lot of research, got a good grasp of the issues — and he eviscerates the Koch and Scaife-funded campaign to derail action. Great pay off line, too.

In the Shadow of Melting Glaciers Bryan Walker May 26

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CareyGlaciersAdapting to climate change is a complex matter for human communities, as Mark Carey makes abundantly clear in his newly published book In the Shadow of Melting Glaciers: Climate Change and Andean Society. Carey is a historian and explores nearly sixty years of disaster response in Peru since the beginning of his story in 1941 when an outburst flood from a glacier lake in the Cordillera Blanca mountain range sent a massive wave of destruction on the city of Huarez, obliterating a third of the city and killing an estimated 5000 people.

There have been further disasters since that one.  Peruvians have, Carey points out, suffered the wrath of melting glaciers like no other society on earth.  Further outburst floods followed in 1945 and 1950, and glacier avalanches in 1962 and 1970 (the latter following an earthquake) killed many thousands.

The Huarez disaster prompted three national government strategies to protect the population from the hazards that the outburst flood had revealed: drain glacial lakes, prohibit urban reconstruction in the flood plain, and build retaining walls in Huarez to contain the glacier-fed Quilcay River. It all sounds quite rational. But only the first was able to proceed. Class and race issues, as Carey sees it, prevailed to counter the plans for hazard zoning and retaining walls. Huarez’s upper and middle classes wished to reconstruct the city in order to re-create the physical characteristics that helped symbolize urban authority and social standing in relation to the rural indigenous population. The socioeconomic order disrupted by the flood was to be restored.  Resistance to hazard zoning and relocation was not confined to Huarez but also occurred in other communities subsequently affected by disastrous outburst floods or glacier avalanches. One local writer reflecting on the triumph of ’human will’ which led to rebuilding in the same places of destruction concluded: ’…[T]hey will be there forever, suffering. stoic, crying through their destiny. And that is the beauty of it, the poetry, the immortality of a people.’ Defiant stuff, and part of the complexity Carey’s book explores.

But though people may have been unwilling to move from where they lived, they certainly supported the draining of glacial lakes and other measures to protect them from further disasters. Not that such measures are simple. Peru struggled to get a picture of the extent of the threat from glacial lakes in the Cordillera Blanca.  Indeed it was not until 1953 that an inventory of how many such lakes there were was finally achieved. There were 223. Today there are more than 400. It’s a growing problem. Once identified, lakes need to be assessed for the danger they pose. This is no easy matter. Accessibility is difficult.  The moraines behind which the lakes build vary greatly in their capacity to retain increasing volumes of meltwater. The incline of the glacier and the likelihood of large falls of ice causing large waves has to be taken into account. When drainage is undertaken the logistics of the operation can be daunting for both machinery and manpower.  Carey describes some of the on-site work as well as the difficulties at the national level of offices trying to carry out the task with limited resources and varying levels of support from successive governments.

Hydroelectricity is a complicating factor in the situation. The Santa River flows north through the valley parallel to the Cordillera Blanca. When it turns west and descends steeply to the coastal plain it feeds the large Cañón del Pato hydro-electric facility. The power station was itself the victim of the 1950 outburst flood, which destroyed it when it was nearing completion. It was the flood’s devastation of this facility and of the Chimbote-Huallanca railway line which transformed the piecemeal disaster prevention measures of the 1940s into the more effective and far-reaching response of a new government agency, the Lakes Commission. Carey notes that it was the setback to national industrialisation plans in 1950 rather than the deaths of thousands in the 1940s which led to this much better resourced body. The hydro-electric power station was rebuilt and, following privatisation in 1996 under Fujimori’s neoliberal progammes, is now owned by Duke Energy. Its generating capacity has increased considerably with successive upgrading.

Glaciers are not only hazards but also resources and Carey records a shift in emphasis after the 1980s from the hazard focus to the measurement and management of glaciers as hydrological resources, particularly for electricity generation and for irrigation. He notes that the information gathered has been of benefit to Duke Energy, a private company based in the US and responsible to shareholders rather than the Peruvian public. Duke Energy has been involved in attempts to retain glacial lake waters as reservoirs for regulating the flow of the Santa River and has encountered considerable local resistance. While glacier retreat has enabled expansion of water use in the region, this is a trend which is likely to change if the glaciers continue to diminish.

Hazards haven’t gone away because of the focus on resource, but the neoliberal agenda of the 1990s brought a severe reduction in the public funding of disaster prevention programmes. Neoliberalism exacerbated vulnerability to natural hazards, and although the state disaster prevention agency reopened in 2001 it never regained the status, budget and support it had in previous periods. Carey is even-handed in his treatment of neoliberalism, but sees it as a theory which collided with historical reality. Some of that reality is manifest in the local resistance which has prevented Duke Energy from managing the waterscape uncontested.

Throughout the book Carey devotes much attention to the ways in which various groups in Peruvian society and the relationships between them have played a part in forming the country’s response to melting glaciers. Many interests have had to be — sometimes have insisted on being — consulted and taken into account. Socio-economic divisions have played a part. Increasing international interest has become part of the interaction. Carey the historian has brought a valuable insight into the way a society functions or malfunctions in facing up to the impacts of climate change. He emphasises the need for understanding social relations and power dynamics at the same time as deciphering how much water will flow from a glacier in fifteen years’ time.

As Carey recognises, the acceleration of glacier melt is an issue not just for Peru but worldwide. Bolivia, Ecuador, Colombia, Nepal, India, Russia, Switzerland, the US and scores of other countries have populations which live near or depend on water from melting mountain glaciers. If there is a message to others from the Peruvian experience it is that disaster mitigation is a political and social process as much as it is a matter of science and engineering. Social conflicts, for example, may be more urgent to people than the potential floods or even water-shortage issues that experts see as the most pressing. It’s not only technical and scientific skills that will be needed but also a sense of social relations and of the perceptions of the populations affected.

As history Casey’s book is an engrossing read. What he recounts hardly leaves one sanguine about the ability of societies to navigate the adaptation requirements ahead as climate change begins to bite, but it offers some useful signposts.

[More at: Fishpond (NZ), Amazon.com (US), Book Depository (UK)]

Down to the sea Bryan Walker May 06

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An interview with climatologist Ellen Mosley-Thompson published yesterday in Yale Environment 360 is a reminder that for those working with ice there’s not much doubt about where we’re heading. She spent six weeks of the summer on her ninth visit to Antarctica drilling ice cores on the Antarctic Peninsula, one of the fastest-warming places on earth. Its winter temperatures have increased by 6 degrees over the past 60 years and year-round temperatures by 2.8 degrees. As a result, sea ice now covers the western Antarctic Peninsula three months less a year than three decades ago, 90 percent of glaciers along the western Antarctic Peninsula are in retreat, and large floating ice shelves are crumbling.

Mosley-Thompson headed a team of six for the drilling, and they were part of a larger group attempting to understand the warming behind the break-up of the Larsen B ice shelf in 2002. Ecologists were looking at an ecosystem on the ocean bottom that until eight or nine years ago had been covered by ice for thousands of years and considering how it is adjusting to the new normal. Glaciologists were looking at how much more rapidly the glaciers are discharging into the ocean with the disappearance of the buttressing ice shelf. A marine group was looking at changes in marine geo-chemistry, collecting new cores in the area that was covered by ice to compare with the cores previously drilled in the ocean bottom along the outer margins of Larsen B when it was in place.

It’s an impressive range of investigation she describes. The ice drilling on the Bruce Plateau was able to get right down to bedrock at 455 metres, and the cores will be closely analyzed back in Ohio for the information they contain about past climate, perhaps to the last glacial period and beyond.

Mosley-Thompson is married to Lonnie Thompson, the highly respected glaciologist. While his wife has been working mostly in Greenland and Antarctica he has done more ice corings of low-latitude glaciers —- in the Andes, Africa, and the Himalayas —- than any other person alive. Yale Environment comments that their work, taken together, paints a sobering portrait of the rapid retreat of most of the world’s glaciers and ice caps in the face of the buildup of planet-warming greenhouse gases.

Here are some of the things Mosley-Thompson has to say in the interview about the overall global picture. In response to the interviewer’s observation that the deep Antarctic ice cores taken at Dome C years show that we have got more CO2 in our atmosphere than at any time in 800,000 years:

’Very clearly. If you look back over the eight glacial/interglacial cycles, you essentially see that CO2 never rises above 300 parts per million and we’re at about 389 now. Methane never rises above about 800 parts per billion, and I think we’re at about 1,700 parts per billion. So we’re clearly outside the range of natural variability. I personally think that graph simply showing the natural fluctuations in those two important greenhouse gases, over almost a million years of Earth history – and then you see the two dots [today] that are so much higher than anything that we see in that near-million history – tells us very clearly that we have a serious problem.’

What does the cumulative ice coring  work show about what we’re experiencing in the last century or so in terms of the warming of the planet?

’ Well, from the tropical work, the cores in the Andes and the Himalaya, the oxygen isotopic ratio in those cores, when you stack those cores together, show very clearly that the last 50 or 60 years have been the warmest in the last 2,000 years.’

The ice cores from the Andes do show a Medieval Warm Period signature and a very distinct Little Ice Age cool signature.  Not surprising, she says, because both those periods are expressed most strongly around the Atlantic Basin and the moisture that builds the glaciers in the Andes of Peru actually comes from the Atlantic.  But the cores from the Tibetan Himalaya show virtually no signature of these periods.

’so when we put these records together, the medieval warming is very modest and the Little Ice Age signature is strongly muted as well. And what really stands out when you put these all together and into the composite, is the last 60 years. The oxygen isotopic enrichment in the tops of the cores [indicating warming] is very striking.’

She notes that particularly in the case of the tropical ice fields the glaciers are retreating very rapidly:

“And, in fact, several of the ice fields, particularly one that we recently published the results [for] in the southwestern Himalaya, it has not gained mass or has no ice that was deposited after 1950. It’s like these glaciers are just literally being decapitated. And it’s very frightening.’

And what about the IPCC error on Himalayan melting?

’…when you look at the breadth of the Intergovernmental Panel on Climate Change reports, and how much information is in there, the fact that this must be the most egregious error, otherwise they would be making more of something else —  I think it’s astounding that the IPCC got as much right as they did because there was just tremendous potential for error.’

And if we don’t begin to rein in CO2 emissions, where is the cryosphere, the Earth’s ice zone, heading?

’To the oceans. Ultimately that’s where all water goes, to the lowest level.’