New Zealand's vanishing snow

I'm no geographer -  (I'm an historian) -  but I can see a more short-term problem. 

What if there are several winters like the one just past where there was a lack of snow due to warming conditions. 

What will this do to Canterbury's snow-fed rivers? What is the implication for agricuture, irrigation etc.?
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This article was republished in the Herald from an Australian newspaper.

This simply isn't being talked about. Mostly we are talking about anecdotes. Most people don't notice, except for an handful of snowboarders or odd people that look up and the laps and notice there is no snow and relate that to past experience.  Most people just take it for granted or enjoy the manufactured snow on the ski slopes.

NZ: Southern Alps snow, ice vanishing

Retreating glaciers and uncovered rocks evidence of swift change in climate with implications for sea level.

NZ Herald,

30 July, 2014

A third of the permanent snow and ice on the Southern Alps has vanished in less than four decades, according to an analysis of aerial surveys.

In an article published on Australian website The Conversation, three Kiwi researchers describe the story of the alps' disappearing ice as very dramatic.

The analysis, by climate scientist Dr Jim Salinger, Otago University Professor Emeritus Blair Fitzharris and glaciologist Dr Trevor Chinn, follows on from a paper published by Dr Chinn last year documenting the retreat of our postcard glaciers.

Partly using aerial surveys by the National Institute of Water and Atmospheric Research, the three authors have calculated the alps' ice volume has shrunk by 18.4cu km or 34 per cent - and those ice losses have been accelerating rapidly in the past 15 years.

When compared with rapid glacier retreats in many parts of the world, the loss raised serious questions about future sea level rise and coastal climate impacts, they said.

In 1977, Dr Chinn began taking aerial photographs to measure the annual end-of-summer snowline for 50 index glaciers throughout the Southern Alps, which are still taken by Niwa.

He and his colleagues have now used Niwa results to calculate the annual glacier mass balance, and to quantify the volume changes of small to medium glaciers in the alps.

These glaciers responded quickly to annual variability of weather and climate, and were in balance with the current climate.

But this wasn't so for the 12 largest glaciers, among them the Tasman and Godley, which had a thick layer of insulating rocks on top of the ice lower down the glaciers' trunk.

"Their response to new snow at the top is subdued, and may take many decades to respond," the authors wrote. "Up until the 1970s, their surfaces lowered like sinking lids maintaining their original areas. Thereafter, glacial lakes have formed and they have undergone rapid retreat and ice loss."

To make the calculations, they used the snowline survey data along with earlier topographic maps and a GPS survey of the ice levels of the largest glaciers to calculate total ice-volume changes for the Southern Alps up until this year.

Over that time, they said, the ice volume had fallen by 34 per cent, or from 54.5cu km to 36.1cu km in water equivalents.

Of that reduction, 40 per cent was from the 12 largest glaciers, and 60 per cent was from the small to medium-sized glaciers.

Veteran mountain guide Shaun Norman described their calculations as astonishing but unsurprising.

An injury in 2000 had kept him off the high alps since then, but even before, the changes had been visible, he told the Herald. "One could see that less snow dumps in quite a few years meant pieces of rock which you knew were always covered suddenly were staying clear for 12 months of the year, and getting bigger."

The World Glacier Monitoring Service estimated the 1890s extent of ice volume in the Southern Alps was 170cu km, compared with 36.1cu km now - a change the authors said was evidence of the local effects of global warming.

Based on regional warming projections of 1.5C to 2.5C, it has been projected by glaciologists Valentina Radic and Regine Hock that just7 to 12cu km of ice would remain on the alps by the end of this century.

Kiwi glaciers do it their way

Research suggests that ancient New Zealand glaciers were out of tune with their Northern Hemisphere counterparts when they grew and subsided thousands of years ago.

The study, published this week in the US journal PNAS (Proceedings of the National Academy of Sciences), goes against an alternative view that our glaciers followed the same patterns as those in the opposite hemisphere between 30,000 and 20,000 years ago, when ice sheets were at their most recent maximum extension.

The study, led by Professor Henrik Rother of the University of Greifswald in Germany, analysed a record of glacier debris in the Southern Alps' Rangitata Valley from between 28,000 and 16,000 years ago.

According to the study, the records of glacier movement preserved in "exceptional detail" showed New Zealand glaciers peaked earlier and retreated more slowly than Northern Hemisphere glaciers, and were only partially influenced by northern climate patterns.

Victoria University researcher Associate Professor Andrew Mackintosh said while the new findings were compelling, whether our glaciers followed their northern counterparts remained an open question.

"One argument suggests that during the last deglaciation, there was a rapid retreat of New Zealand glaciers that was more or less synchronised with those in the Northern Hemisphere, and there's good evidence for that from a numbers of sites here," he said.

"Then there's the alternative that the ice stuck around for a bit longer, which this study is reinforcing. It's hard to know which one will stand the test of time."

 Read the full article HERE

Missing from New Zealand's Ski Slopes This Season? Snow!

The Remarkables ski area near Queenstown — one of few New Zealand ski areas that has been making snow the warmest start to winter ever recorded. Scientists said New Zealand’s glaciers and ice are melting at alarming rates due to climate change. (AP Photo/Richard Savoie)

Yahoo,

6 August, 2014

Winter has rolled into its third month in New Zealand, and Nick Jarman says he’s going stir crazy as he stares out at the driving rain on the small ski area he manages in the Southern Alps.

The Craigieburn Valley Ski Area is one of several areas that haven’t opened for a single day this season, and some fear there may not be enough snow to open at all this year — something Jarman says has never happened during his 30 years carving turns on the mountain’s slopes.

Ski operators throughout New Zealand are feeling the effects of the country’s warmest start to the Southern Hemisphere winter since record-keeping began in 1909. And while one bad season doesn’t prove a trend, it comes at a time when scientists say the country’s snow pack and glaciers are melting at an alarming rate due to climate change.

The country’s largest ski areas have managed to open only because they’ve invested in equipment to make their own snow, which they’ve been doing this year in unprecedented quantities. For now, at least, that’s helped protect the nation’s reputation as a winter play land, one that each year attracts more than 60,000 skiers and snowboarders from Australia alone from June to August when it is winter south of the equator.

At Queenstown’s Coronet Peak, 200 snow guns have been blazing day and night whenever the temperature dips a little below freezing. Those guns have turned enough water to fill 100 Olympic-size swimming pools into a white blanket that’s remained on the main trails even on days when some skiers have taken to wearing t-shirts.

But New Zealand also has a tradition of small ski areas that rely entirely on natural snow, and many are facing steep financial losses this year. Typically, the areas are run as nonprofits. They are kept open not only by tourist dollars but also from the work of enthusiastic volunteers. Operators of these areas say they can’t afford to invest hundreds of thousands of dollars in snow-making equipment.

Jarman says Craigieburn employs about 10 staff but can only pay them once the area opens. He says it’s not just the ski areas that are suffering, but also the local ski rental stores, the gas stations, even the bakeries. He says he’s been refunding money to tourists who have booked ski and accommodation packages, and the season is putting a strain on Craigieburn’s finances.

"It’s going to be hard, really hard. We don’t have the extra money to spend on maintenance," he says. "We’re not living on caviar and salmon."

It’s a similar story at Mount Cheeseman Ski Area, which employs about 20 staff when there is snow, but which also hasn’t been able to open. Mountain manager Cam Lill says some of his staff, who come from abroad, are taking the opportunity to tour the country while others are earning money doing odd jobs