There have been more than a few echoes reverberating from New Zealand's mountains in recent months.
These have ranged from complaints about tourism's more noisy effects to scientific observation of shifts brought about by massive seismic forces and an incessant glacial melt.
Comprising rock and ice, our alpine spine might loom large and solid, yet it is fragile.
Tomorrow, more than 120 participants from around the world, including land managers, alpine advocates, scientists, iwi, guides and adventure tourism operators, will gather for a global Sustainable Summit Conference at Aoraki/Mt Cook, where they will discuss how to adapt to a changing landscape.
The first of its scale to be held in New Zealand, the two-yearly conference (it has previously been hosted by the United States) will cover three core themes: environmental impacts (human waste, water contamination, noise pollution); natural hazards (global warming, ice recession, unstable geology, avalanches); and social/cultural impacts (increasing numbers, commercialism, and awareness of areas sacred to Maori).
"We are pretty sure there will be a lot of divergent views," Dave Bamford, a co-ordinator of the conference says.
"If you are in the tourism industry, you may have a different approach to people for whom the mountains hold spiritual and cultural values. If you are an amateur climber you may have a different perspective to a professional climber as regards air access into the mountains."
Although the conference is focused on issues above the snowline (Bamford: "We might not talk about the Rees-Dart track, but we might discuss Cascade Saddle and French Ridge Hut ..."
), to get to the top, one has to sometimes start at the bottom (planes or helicopters notwithstanding).
The Ministry of Business, Innovation and Employment forecasts overseas tourist visitor numbers will grow 4% per year, reaching nearly 3.8 million by 2021.
That equates to a total spend of $11.1 billion, up nearly 50% on 2014's total visitor spend of $7.4 billion.
"If you look at tourism's growth, we have had a huge increase in arrivals, from 2.9million in 2014 to 3.4million last year. Even the arrivals for the month of June this year were up 15%."
These figures encompass those who choose to visit our cities, our rural areas, our back country and our mountains.
Significantly, the New Zealand Tourism Strategy includes an intent to disperse visitors into more remote areas and spread the load across seasons.
Bamford points out visitors to Aoraki National Park are likely to broach 500,000 for the past year.
Those tourists flow into the sub-alpine areas such as the Hooker Valley, but also Mueller Hut which, at 1800m, offers streams of backpackers a front-row vista that includes Mt Cook and Mt Tasman.
"I think New Zealand is a bit complacent about managing our alpine areas, because we haven't had the same sort of pressure as experienced overseas, like Mont Blanc."
(The 4809m Mont Blanc, in the French Alps, attracts more than 30,000 people per climbing season. To offer a southern New Zealand comparison, Bamford says about 200 climbers attempt to summit Mt Cook each season.)
Despite the yawning gulf between those figures, New Zealand can learn from and adapt overseas examples, says Bamford, a tourism and development consultant who has worked in 40 countries and lent his expertise to the Government and interested parties in the establishment of the national cycle trail network.
"Two years ago I went to the summits conference in Colorado to learn more about this subject. I sat there and learnt about how human faeces deposited on a mountain could end up in water supplies, complete with pathogens.
"It was a wake-up call, one of those lightbulb moments. I've since put my energies into promoting the discussion of alpine issues.
"This has coincided with this tourism boom. On one hand it's great that more people are coming here, but on the other we need to minimise the impact.
"Having speakers share their experiences of management at places including Everest, Denali [Alaska] and Mont Blanc will keep the conference focused on solutions to the growing challenges of sustainability of our 'precious' mountains."
Lou Sanson, director-general of the Department of Conservation, is well aware of the growing pressures of tourism in the high places.
"There have been big jumps in certain areas. Take a place such as the Eglinton Valley, where camper numbers now number 55,000 a year. Three years ago, that number was 15,000.
"The alpine tourism that is in really high demand now is glacier landings. The operators at Milford Sound would say the Chinese market comprises about 90%.
"There is very high demand for those iconic landscapes - Whakapapa, Aoraki/Mt Cook, Milford Sound, Fox and Franz Josef glaciers - and connected with all these has been huge demand for people wanting snow landings."
Let's add another landing site to that list.
Ngapunatoru Ice Plateau, on Mt Tutoku in Fiordland National Park.
Recently, documents obtained under the Official Information Act revealed Doc and the aviation industry held closed-door meetings in a bid to significantly increase helicopter landings on the plateau.
Despite a Doc management plan allowing for only 10 per day, landings had been increased to up to 80.
The document also outlined concerns raised by affected groups, including Ngai Tahu and Federated Mountain Clubs, about a lack of consultation and detail about the increase in flights.
In an interview with the Otago Daily Times this week, Sanson described Doc's flouting of its own management plan as a ''trial'' held over the past summer.
"We put in place a research project and we will be working through that with Ngai Tahu, the Federated Mountain Clubs and tourism operators to assess the impact of up to 80 landings a day.
"We haven't reached a final decision. We have to balance what is required for tourism without inhibiting the natural quiet and values of climbers and, importantly, the spiritual values of Ngai Tahu.''
A core concern is noise pollution.
A keen tramper himself, Sanson acknowledges the issue "goes to the heart" of Kiwis' love of the wilderness.
"Many people in tramping clubs have grown up in an environment where they can walk for many days [in relative peace] and now feel the effects of aircraft are detracting from that experience.
"It is an issue we have to resolve between tourism and back-country users. We would like to think there is room for both. I have heard both sides of the argument. However, I wouldn't want to pre-empt what that solution is."
It is a balancing act, Sanson says, between overseeing the recreational use of its estate (including working in partnership with businesses) and adhering to a mandate that, traditionally, focused on conservation.
"Doc can't control tourism. Let's just put that on the table. But we have to ensure people are getting a quality experience when they are here. We have been surprised by this huge increase in tourism over the past two seasons. And there is potential for it to grow by between 10% and 20% this year."
He points out that 50% of all arrivals come to New Zealand primarily to experience nature.
Some are under time constraints and thus focus on a pipeline that, typically, encompasses Auckland, Rotorua, Taupo, Christchurch, Franz Josef, Fox, Queenstown and Milford Sound.
But that pipeline is only going to get busier. And it has a spillover effect.
Take the Hooker Track, a three-hour walk that now attracts close to 300,000 people a year to Aoraki National Park.
"Yet I could go 40 minutes further away and be in an alpine valley on my own."
Sanson says climate change is also a factor, changing the behaviour of pests, plants and people.
"We are also seeing an increase in wilding pines in alpine areas because of warmer winters; we are getting introduced species, including rats and stoats, expanding their range. Because of this we are worried about the kea, an alpine bird. Climate change is giving predators a nudge.
"We also had the shortest climbing season at Mt Cook this year because crevasses appeared really early. That then led to a premium on helicopter landing sites."
And therein lies an irony, according to New Zealand glacier expert Brian Anderson.
"Glaciers are retreating because of climate change caused by greenhouse gas emissions. Yet one response to that change is to access the glaciers through a more intensive method.
"All of the tourism operators are extremely conscious about safety. And that does mean more helicopter access as a means of keeping operations going. Obviously, that has an impact on other users of national parks."
Dr Anderson, of Victoria University's Antarctic Research Centre, says the latest measurements for Fox Glacier and Franz Josef Glacier show they have retreated 750m and 1.5km respectively in the past five years.
That decline follows a study last year that found the Southern Alps' ice volume had shrunk by 18.4cu km (or 34%) in just four decades, the trend accelerating in the past 15 years.
The World Glacier Monitoring Service estimates the extent of ice volume in the Southern Alps in the 1890s was 170cu km, compared with just over 36cu km now.
And based on regional warming projections of 1.5degC to 2.5degC, some glaciologists predict only 7 to 12cu km of ice will remain on the Southern Alps by the end of this century.
"There is no doubt glaciers such as Fox and Franz aren't as spectacular now as they were in the late 1990s, when they were advancing and had steep fronts that would break off," Dr Anderson says.
Having measured glaciers for 20 years, both in New Zealand and further afield, including the Antarctic, the scientist has also witnessed another phenomenon.
"People come to see glaciers for particular reasons. That includes visitors coming exactly because they are retreating, so therefore they are only going to get smaller and harder to see.
"It's part of the concept known as `last-chance tourism'. Glaciers are retreating globally, which could lead to a notion of competitive advantage, as in, if ours survive longer than others elsewhere, it could drive more visits."
At the risk of pointing out the obvious, a glacier is simply the result of surplus ice that collects above the snowline; it carries snow and ice from a high place where it can't melt to a lower altitude where it can.
That means if there is more snowfall and lower temperatures, a glacier gains mass and responds by advancing.
"A glacier is always trying to balance itself. Glaciers are a particularly sensitive part of the alpine system. They are made of snow and ice and are zero degrees. So if the temperature increases even slightly, they are going to start melting.
"Obviously, the biggest glaciers have the most economic value in terms of tourism.
"But some of the other ones have implications for tourism also. For example, there might be a particular access route to a mountain that requires people to pass over a glacier. And if that retreats it can make access impossible.''
Mountaineering: a rough guide
According to the New Zealand Mountain Safety Council's recent publication, There And Back, more than 26,000 Kiwis are involved in mountaineering; however, the publication didn't have figures for overseas climbers.
Rachel Fogarty, a Department of Conservation ranger based at Mt Aspiring National Park's Wanaka centre, says it's difficult to quantify climber numbers, "because we mainly deal with tracks rather than climbs".
Numbers collated by the hut warden based in Aspiring Hut showed more than 1100 people stayed at that climbing base between October 2015 and April. Mike Davies, Doc's Aoraki/Mt Cook District operations manager, points out that the use of huts in the national park is nonetheless the best indicator of climbing activity.
"I have no data on climbers who don't use huts but it is assumed to be a low figure in comparison to the use of huts. Huts provide a base, allowing the opportunity to undertake climbs.
"There are nine huts that are used specifically for climbing [in the national park]. The most used is Kelman Hut at 1086 bed-nights per year, through to Haast Hut, at eight bed-nights per year.
"Looking at the data, the trend for climbing in Aoraki is static tending to a decline. This is most likely a result of the difficulties of glacier access as well as changing patterns of use driven by cost/less time. This creates a narrower window of opportunity to undertake climbs based on the weather and access conditions."
Sustainable summits
Mountains are precious reservoirs of biological diversity, hosting a vast variety of plants and animals - as well as people. In global terms, one in 12 people - around 700 million individuals - live in mountainous regions.
Mountains are the water reservoirs of the world, providing fresh water to at least half of the world's population. They play an important role in influencing global and regional climates and weather conditions yet are fragile and are now experiencing environmental degradation (ranging from soil erosion, landslides, loss of habitats and species), and are particularly vulnerable to pressing changes such as global warming.
Hence the importance of the Sustainable Summits Conference at Aoraki Mount Cook, its organisers say.
The conference, which started yesterday, will focus on practical solutions to adapting to a changing mountain environment, responding to changing visitor patterns and behaviour, and preserving mountains for the enjoyment of future generations.
The five-day event has attracted more than 120 participants from around the world. Presenters include high-profile mountain advocates such as Lou Sanson, Director-General of the department of Conservation; Guy Cotter, CEO of Wanaka-based Adventure Consultants; Dawa Steven Sherpa from Nepal; Peter Rupitsch, managing director of Hohe Tauern National Park, the largest national park in the European Alps; and Roger Robinson, a 40-year member of the American Alpine Club.
The summit will be held in The Sir Edmund Hillary Centre in the Hermitage.
For more information, visit www.sustainable-summits.com
