Australian Institute of Alpine Studies

Newsletters

No. 4 November 1998

Contents


1998 Winter Snow

U.N. Names 2002 as "Year of Mountains"

Tourism in Kosciuszko National Park: Planning for Change

Articles:

Mountains on the Agenda

More News From Overseas

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1998 Winter Snow

The winter of 1998 was another poor snow year in the Snowy Mountains, but this time we were able to monitor snow trends at a mid-altitude site. Traditionally the commercially available graphs of snow cover are based on what happens at the Snowy Mountains Hydro-electric Authority snow course at Spencers Creek (1830m). This is their only regular course in the south end of the snow country; they also collect weekly data from snow courses at Deep Creek (1620m) and Three Mile Dam (1460m). This year for the first time the NSW NPWS collaborated with the SMHEC to collect regular data from the snow course at Whites River (1680m). The following graph shows that what happens across the subalpine zone is not necessarily represented by the Spencers Creek snow course. Being at the higher altitude the snow depth at Spencers Creek was less affected by the rainfall episodes (the troughs following the peaks at Whites River) because of the greater snow mass and the possibility that some of the precipitation may have been falling as snow. Monitoring at the Whites River site in the past has only been on a monthly basis but will continue hereafter on a weekly basis to provide better data on mid subalpine altitudes.

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U.N. Names 2002 as "Year of Mountains"

On 10 November 1998 the General Assembly proclaimed the year 2002 as the International Year of Mountains, intended to promote the sustainable development of mountain countries. Acting without a vote, the Assembly approved a resolution recommended by the U.N. Economic and Social Council and sponsored by 130 of the 185 U.N. members.

Introducing the resolution, ambassador Zamira Eshmambetova of Kyrgyzstan said mountains or highlands made up more than a quarter of the Earth's land surface and were home to approximately 10 percent of the world's population. She said more than half of the world's people depended on mountains for resources such as water and activities such as recreation, agriculture, forestry and mining.

Following interventions declaring their support for the Year from the representatives of Nepal and France in addition to Kyrgyzstan, the draft resolution was adopted by consensus. The resolution:

(1) Proclaims the year 2002 as the International Year of Mountains;
(2) Invites the FAO to serve as the lead agency for the Year, in collaboration with Governments, the United Nations Environment Program, the United Nations Development Program, the United Nations Educational, Scientific and Cultural Organisation and other relevant organisations of the United Nations system and nongovernmental organisations ;
(3) Calls upon Governments, national and international organisations, non governmental organisations and the private sector to make voluntary contributions in accordance with the guidelines of the Economic and Social Council for international years and anniversaries and to lend other forms of support to the International Year of Mountains;
(4) Encourages all Governments, the United Nations system and all other actors to take advantage of the International Year of Mountains to increase awareness of the importance of sustainable mountain development;
(5) Requests the Secretary-General to submit to the General Assembly at its fifty fifth session a report on the state of the preparations for the International Year of Mountains.

There will be a great need for continuing and improving partnerships and networking to avoid the International Year of the Mountains, becoming just another year disregarded in Australia because of a perception of our lack of mountains. So are there any ideas out there?

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Tourism in Kosciuszko National Park: Planning for Change

Funding has been obtained by Dr Catherine Pickering and Dr Jan Warnken, School of Environmental and Applied Science, Griffith University and Graeme Enders, NSW NPWS from the Co-operative Research Centre for Sustainable Tourism for a three year project examining human impacts in the alpine region of Kosciuszko National Park titled Tourism in Kosciuszko National Park: Planning for change

The Australian Alps are one of the most heavily used natural areas in this country. Kosciuszko National Park is the third most visited national park in Australia with over three million people visiting each year (Good, 1992). The region is also in close proximity to almost two thirds of Australia's population. The intensive use of this area poses a major threat to the region's ongoing tourism and biological viability. The value of recreational activities centred on the park is significant with dollar value in the local region estimated to be $110-140 million annually (Good 1992). Continued tourism in the alpine region is only possible if it does not threaten the ecological sustainability of the region, as NSW NPWS has a legislative obligation to protect and maintain the environment. Development of a database and series of predictive models that cover historical, current and future human impacts on the alpine region will allow evaluation of the relative importance of tourism associated impacts, and the development of effective management strategies so that tourism can continue in the alpine region.

The high cost of infrastructure established for skiing and other winter sports is driving the exploitation of this region for recreation year-round. In winter the dominant activity is skiing. This activity requires expensive specialised infrastructure. Limited skiable snowfields, slope capacities and the short ski season, restrict this use. In recent times resort operators have sought to diversify and exploit the region through summer tourism focusing on activities such as car touring, fishing, walking, etc. These summer pursuits have increased in both intensity and in types (Good 1992).

The expanded use of the alpine region for summer based tourism will be in conflict with the National Parks legislative objectives to protect the inherent biological values of the region unless effective management of visitor use can be implemented. NSW National Parks and Wildlife service are currently developing a nature tourism and recreation strategy to improve the management of visitor use of for all National Parks within NSW. To be able to do this for the most intensively used National Park, Kosciuszko, requires a clear understanding of the changing process that are occurring in the alpine region as a result of the different types of human induced impacts. The three most important human impacts are: (1) grazing - a historical impact that the region is still recovering from; (2) tourism - the current major human activity in the park; and (3) climate change - potentially the greatest threat to the region.

The relative importance of these different impacts will be assessed by comparing changes in the alpine region as a result of historical process, current impacts and future developments and climate change. Information about each of the types of process and their known or predicted impacts will be incorporated into a database and used to develop a series of maps showing the effects of the impacts on the region. The development of such a database and map is a vital part of the planning process for effectively managing tourism according to the draft Nature Tourism and Recreation Strategy. It will directly facilitate the economic and ecologically sustainability of tourism in the region, now and in the future.

The initial part of the project involves the development of an up to date database and model that graphically displays the current state of the natural environment and human usage of the alpine region. Different components of the model will address the topography, soil types, plant communities, human infrastructure (roads, trails, car parks), areas of high impact, and human usage patterns and intensities. NSW NPWS will provide topography and soil data. Aerial photographs in combination with ground truthing will be used to obtain information about the current state of the flora and areas of high impact. Information about human usage patterns and intensities will come from existing information provided by NSW NPWS and from visitor surveys. From these data an accurate idea of the relative importance of current impacts can be developed and used by NSW NPWS to assess the sustainability of current tourism activities.

The second component of the project involves adding historical information to the map and database. By comparing models generated from historical data with the current model, the location and degree of change in the region as it recovers from grazing and as tourism has expanded in the alpine can be examined. Previous vegetation, soil, and human usage maps and data will be provided by NSW NPWS, Snowy Mountains Authority and from scientific studies of the region. Additional information concerning the change in vegetation, and recovery of soils and water quality from grazing will be obtained from field work remapping old transects used by the Soil Conservation Authority in the 50's and 60's. The final stage of the project involves investigating future changes in the region, both climatic and in tourism. A third level to the model and database will be developed using information from CSIRO climate change models, along with projections of future tourism use and intensity. Information concerning potential increases in tourism in the region will be provided by NSW NPWS and from models developed as part of this project. From this information predictive maps of the region under different scenarios can be developed to investigate the relative importance of the different impacts, and to determine the relative effectiveness of different management strategies on the region.

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Articles

The Influence of Aeolian Dust Deposits on Alpine Soils in South-East Australia.
Stuart Johnston
NSW National Parks and Wildlife Service
PO Box 2228, Jindabyne NSW 2627

The presence of aeolian dust in montane and alpine soils has been debated for several years around the world. In Australia it is thought that the accession of aeolian dust across the mountainous areas of the south-east has played a significant factor in the development of alpine soils, in particular snowpatch meadow soils (Walker and Costin 1971). The clay content (<0.002 mm) of these soils is comprised of several origins such as current chemical weathering, weathering prior to periglaciation, the decomposition of the deep-rooted alpine/subalpine vegetation to produce colloid sized sesquioxides at the soil surface and dusts (resembling parna) blown in from the semi-arid and arid zones of Australia (Costin, Hallsworth and Woof, 1952, Costin, 1986). The latter two processes are a major factor in why these soils resist podsolisation. Dust accessions of the order of 20-1000 tonnes per hectare, depending upon site and aspect, are estimated to have occurred on alpine soils in the Kosciuszko region during postglacial times. Walker and Costin (1971) found that the dust collected from snowpatch soils in leeward sites in which there was maximum snow accumulation, had a median diameter of 4 mm, relatively high organic content, and mineralogy in the less than 2mm fraction dominated by illite and kaolin. Snowpatch meadow soils exhibited 47% clay and 22% silt and alpine humus soils 21% clay and 8% silt, with the clay contents being dominated by Kaolin. These findings are supported by Johnston (1995, 1998) where alpine meadow soils exhibited 45-46% clay and 21-23% silt and alpine humus soils 18-22 % clay and 9-17% silt.

References Cited:
Costin, A.B. (1986).Genesis of Australian Alpine Soils. In. 'Flora and fauna of alpine Australasia; ages and origins'. Barlow, B.A. (Ed.). CSIRO, Melbourne, pp. 37-44.

Costin, A.B, Hallsworth, E.G. and Woof, M. (1952). 'Studies in paedogenesis in New South Wales. III. The alpine humus soils'. J.Soil Sci., 3: 190-218.

Johnston, S.W. (1995). 'Zinc toxicity in short and tall alpine herbfields, Carruthers Peak, Kosciuszko National Park, NSW.' Honours Thesis, ANU.

Johnston, S.W. (1998). 'Managing degraded alpine humus soils in Kosciuszko National Park N.S.W.: 1 - soil properties'. Proc. ASSSI Nat. Soils Conf., Brisbane.

Walker, P.H. and Costin, A.B. (1971). Atmospheric dust accession in South-Eastern Australia. Aust. J. Soil Res., 9: 1-5

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Declining Frog Populations in the Australian Alps: Where are we after ten year?
Will Osborne and David Hunter
Applied Ecology Research Group and CRC for Freshwater Ecology University of Canberra

The growing list of frogs reported to have suffered from severe declines in their populations, or even extinctions, has raised considerable international concern. While the declines of some species have been attributed directly to the activities of humans (e.g. draining wetlands, habitat destruction, competition with introduced species), many disappearances of amphibians have occurred in apparently undisturbed habitats, particularly at high altitudes. Unexplained declines and disappearances of amphibians at high elevations have occurred in many mountainous regions along the eastern coast of Australia, from the Wet Tropics to the southern Australian Alps. Failure to identify the cause of these declines has led to much speculation as to whether they are the result of long-term natural cycles, population fluctuations or are a sign of some form of human impact on amphibians. The lack of consensus in this debate has been compounded by our lack of knowledge of the biology of most species.

Declines of frog populations in the Southern Highlands of New South Wales were first observed in the early 1980's (Osborne 1986, 1989, 1990). The species involved included several pool-breeding species found at subalpine and alpine elevations: the Alpine Tree Frog (Litoria verreauxii alpina), the Southern Corroboree Frog (Pseudophryne corroboree), and the Northern Corroboree Frog (Pseudophryne pengilleyi). The Alpine Tree Frog has now disappeared entirely from the alpine zone in the Snowy Mountains where it was once abundant. It also has disappeared from the Bimberi Range near Canberra. This distinctive subspecies persists at a few isolated sites associated with deep artificial water bodies at low elevations. In Victoria the frogs have disappeared from the Bogong High Plains, but are still common on the slightly lower elevation Dargo High Plains and near Dinner Plain and Horsehair Plain east of Mount Hotham. The Southern Corroboree Frog has suffered an extensive decline throughout its range. Most remaining populations are reduced to a few individuals and the species is in imminent danger of extinction. The Northern Corroboree Frog has declined extensively at subalpine sites on the Bimberi Range, but remains common at montane sites (below about 1200m) in the Fiery Range.

It has now been over ten years since the disappearances and declines were first noticed in the alps - we think that the onset of the declines was in the early 1980's; a period that coincided with a particularly severe drought. In the same decade there has been an enormous growth of interest in frogs, particularly in their value as indicators of reasonably healthy catchments and wetlands. Developing eggs and tadpoles have been found to be sensitive to chemical contaminants as well as to excessive amounts of ultraviolet radiation. A number of societies and community groups interested in frogs has formed in recent years - these include the ACT Herpetological Association (ACTHA), the NSW Frog and Tadpole Study Group (FATS) and the Victorian Frog Group (VFG). This community interest, and the concern expressed by field biologists, has focussed attention on the welfare of Australian frogs. This interest culminated in the publication of the Action Plan for Australian Frogs (prepared by Mike Tyler), the formation of a national working group for declining amphibians and financial support for recovery programs for species such as the Baw Baw Frog (Philoria frosti), Southern Corroboree Frog (Pseudophryne corroboree) and Spotted Tree Frog (Litoria spenceri).

But has this interest and support been enough to enable us to prevent further declines; has it lead to implementation of surveys and monitoring, and, importantly, the identification and removal of the causes of the declines? Whilst we now know more about the extent of the declines, we still do not know the factors causing decline in almost all endangered species. In the remainder of this article we report briefly on our own research efforts at the University of Canberra, and in conjunction with the NSW National Parks and Wildlife Service, to address this problem.

We have focussed our research on three species that are in serious decline in high altitude regions of the Snowy Mountains and adjacent mountain ranges (Fiery Range, Bimberi Range, Brindabella Range). We have attempted to address the question of whether each species really has declined to a critical level and now, through a combination of observation and experimental work, we are in the process of attempting to establish the factors that might be leading to the population declines. Finally we have initiated a joint program with the NSW National Parks and Wildlife Service and the Amphibian Research Centre (in Melbourne) to attempt to increase the size of remnant populations of the Southern Corroboree Frog experimentally. This is being done by a combination of captive husbandry and in situ manipulation of pond water levels to prevent egg and tadpole mortality.

Is ultraviolet radiation responsible for declines in alpine frogs?
This research relates to our knowledge that there has been considerable depletion of stratospheric ozone over the past two decades, and that this has resulted in increased levels of ultraviolet-B radiation (UV-B). Ozone depletion appears to be most severe in the Southern Hemisphere and UV-B radiation may therefore be of particular concern in Australian amphibian declines. This is particularly likely to be the case at high altitudes where UV-B levels are significantly higher than in adjacent lowlands. In research that we recently completed (Broomhall et al. in press) we carried out experiments in artificial water bodies established at three altitudes (1360 m, 1600 m, and 1930 m) near Thredbo in the Snowy Mountains.

We compared the survival of eggs and young tadpoles that were shielded from UV-B (by means of clear plastic UV-B filter) with the survival of other replicates not provided with filters. We also established controls which had a filter that actually let UV-B through. The results were quite dramatic. At all altitudes the blocking of ultraviolet-B significantly enhanced the survival of the declining species, the Alpine Tree Frog. Without protection from UV-B, tadpoles of the Alpine Tree Frog invariably died. By contrast, a non-declining species, the Common Eastern Froglet (Crinia signifera) survived in much higher numbers under all treatments, although there was also a significant effect of UV-B, particularly at the higher altitude sites. The results strongly support the hypothesis that ultraviolet radiation is a factor in the disappearance of the Alpine Tree Frog at high altitudes - it still persists at a few low altitude sites, usually in association with deep artificial ponds with somewhat murky water. This last observation is important because we know that murky water high in dissolved organic carbon provides a very effective shield against ultraviolet radiation. We are currently continuing our studies to include similar experiments conducted in natural water bodies at different elevations in the Snowy Mountains.

Is the decline related to climate change?
Some people have suggested that the worlds climate may be changing, a direct consequence of the 'enhanced greenhouse effect'. Scientists have developed sophisticated predictive models which show that with increasing global temperatures, alpine areas are likely to be amongst the first to be affected. Species confined to these areas are likely to be under significant risk. Many of the endemic frogs found in alpine areas are likely to be particularly sensitive to climatic change - they are dependent on shallow pools, which in the case of the corroboree frogs, must continuously contain water for periods of six to eight months. The frogs are particularly vulnerable to dry conditions that may desiccate eggs or cause the shallow bog pools and seepages to dry earlier in the season.

Monitoring of populations of the Southern Corroboree Frog over the last 12 years indicates that there has been a substantial decline in the population with a gradual contraction of the geographic range of the species to the wetter more westerly part of its former range. Our research, not yet published, examined whether long-term changes in weather patterns may have been responsible for the decline. We found that annual fluctuations and longer-term oscillations (related to the El Nino southern oscillation) characterise the precipitation record in the Australian Alps during all of this century. We found that the onset of the declines in alpine frogs coincided with particularly severe droughts during a long period of below average precipitation (1979-1987). What is surprising to us, though, is that there has been no sign of recovery in the frog populations despite a return to more favourable weather conditions during the 1990's (excluding the recent drought which once again had a severe effect on both species of Corroboree Frog).

The population dynamics of declining alpine frogs.
One facet of our research is directed at obtaining information on the population dynamics of declining alpine frog species. Prior to this research it was believed that the Southern Corroboree Frog only lived for three years (two years as a sub-adult and one year as a breeding adult), however through the use of skeleto-chronology - a technique whereby age is determined through counting growth rings in bone cross-sections obtained from museum specimens, we now believe this species may live for up to seven years. These data, and similar data obtained on the Northern Corroboree Frog and Alpine Tree Frog, are important for interpreting the results of the long term monitoring program for these species. Information has also been obtained indicating that high levels of mortality during the egg and tadpole stages may be contributing to the continued decline in the Southern Corroboree Frog and that this level of mortality is probably being exacerbated by the small size of remnant populations.

Attempts to increase the size of small remnant populations of the Southern Corroboree Frog.
In an attempt to arrest the continued decline and extinction of small remnant populations of the Southern Corroboree Frog, a population augmentation project was commenced in 1997. The aim of this project is to increase the size of several small populations of this species by increasing the level of survivorship from egg to metamorphosis. This is being done by a combination of captive husbandry and in-situ manipulation of pond water levels to reduce egg and tadpole mortality. To confirm whether our captive rearing procedure is in fact reducing mortality during these early life-history stages, a comparison of survivorship between captive-reared and natural field-reared tadpoles was undertaken. The results indicate our ability to increase survivorship significantly via captive rearing with the greatest level of field mortality occurring during the over-wintering stage - field mortality has been very high, with many clutches failing completely.

It appears that with reduced Autumn rainfall the eggs are not hatching, and that the encapsulated tadpoles are then dying due to freezing of the oviposition site in early winter. By removing eggs and raising them in the laboratory, or by placing well-advanced eggs directly into the pools before winter, we have greatly increased survivorship through to metamorphosis the following summer. As the Southern Corroboree Frog takes from two to three years to reach sexual maturity, we will not be able to test the results of our efforts until the year 2000; at this time we expect to see a significant increase in the number of adults at our experimental sites when compared to control sites where no manipulation is being undertaken.

Working with alpine frogs has been an exciting component of our research program in the Applied Ecology Research Group at the University. It is our belief that several of these unique alpine frogs will be faced with extinction unless the causes of decline are identified and removed. Our experimental efforts to increase the size of local breeding populations hopefully will give us the extra time that we need to resolve this important conservation issue in the Alps.

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Mountains on the Agenda

Recent events have confirmed that mountain ecosystems are high on the global agenda. The COP IV of the Convention for Biological Diversity agreed that in the year 2001, the COP VII will focus on biological diversity in relation to mountain ecosystems. In July 1998, the UN Economic and Social Council (ECOSOC), supported by 106 countries agreed to recommend to the 53rd Session of the UN General Assembly to proclaim the year 2002 as the International Year of the Mountains (IYM).

Unfortunately, a number of catastrophic events (e.g. flooding in China and mudslides in Italy) have called attention to the importance of mountain forests in the livelihood and security in mountain areas and conservation efforts are increasing attention on the rich mountain biological diversity and landscapes; all this calls for more mountain initiatives. Experts have said that mankind played a hand in giant landslides that are feared to have killed hundreds in the Himalayan hills of north India. Amid reports that the death toll from the landslides could top 300, a finger of accusation was pointed at deforestation on the steep foothills of the world's highest mountains. "Landslides of the sort we have been witnessing in the Himalayan region have nothing to do with nature's fury a popular explanation to cover man's rapacious plunder and neglect of the environment," The Times of India wrote in an editorial.

"Tonnes of topsoil from the mountains are washed down every year as a result of wanton deforestation," it said. "If this continues, it is feared that the fragile Himalayan range will lose all its forest cover by the middle of the next century." Dr. S.P. Banerjee, a soil expert and visiting fellow of New Delhi's Tata Energy Research Institute, said there were various reasons for slides that strike every year when monsoon rains lash the hills. But deforestation was the main culprit. He said the Almora hills, through which the Hindu pilgrims caught in Tuesday's landslide at Pithoragarh district may have passed, had 53.6 percent forest cover. But barely half of that was under the control of the Forest Department and the rest was not systematically managed.

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More News From Overseas

ORGANOCHLORIDE POLLUTION IN MOUNTAIN REGIONS
David Schindler, from Alberta University, says his team has shown for the first time the extent of organochloride pollution in mountain regions. Analysis of snow samples from mountains in western Canada showed that organochloride accumulation increased drastically between altitudes of 770m and 3,100m.

Writing in Nature, the researchers said: "There is reason to believe that levels of organochlorides in snow would continue to increase at higher elevations. "Cities like Denver and Mexico City derive their water supply from snow melted on mountains over 3,000m high. They are also much closer to industrial and agricultural sources of contaminants." The Alberta team says that there is likely to be a "more pronounced accumulation of toxic compounds" in such areas than in the snows of their study area.

THE QUELCCAYA ICE CAP IS MELTING.
In the Andes the great Quelccaya ice cap, home to some of the hemisphere's largest glaciers, is melting. The losses were small when first detected 30 years ago, but accelerated in the 1990s. Scientists aren't sure why, but some suspect global warming. "Where it was shrinking at three metres a year, it's now up to 30 metres," said Ellen Mosley-Thompson, a glacier expert from Ohio State University.

From the Andes to Montana's Lewis Range, dozens of glaciers are melting as global temperatures climb to the highest levels in recorded history. But despite increasingly strong signals of possible change in the climate, international efforts to slow global warming are stalled.

At Buenos Aires governments could only point to paltry progress on climate change over the last 11 months, and many are dampening expectations for significant achievements in cutting emissions of greenhouse gases this year.

"For the first time, the glaciers are moving literally faster than the negotiations," said Christopher Flavin, vice president and senior climate researcher at the Worldwatch Institute, a Washington think tank. The fear, he said, is that "time could be running out for both."

The two-week United Nations-sponsored climate conference began near the close of a year that will be remembered for its bizarre weather. For reasons that may or may not be related to global warming, Mother Nature cranked up the thermostat this year, pushing global temperatures to records in each of the first nine months. The year 1998 is on track for being the warmest in at least six centuries, or about as far back as scientists can reliably read the weather. Some blame goes to an unusually severe El Nino, yet the global heat pump has continued chugging long after El Nino fizzled out over the southern Pacific.

"We have never seen a sequence where we broke records every month in a row," said D. James Baker, administrator of the National Oceanic and Atmospheric Administration. "It doesn't prove that you have global warming, but it's absolutely consistent with what you'd expect."

To many observers, the peril in Buenos Aires is that nations will fail to agree even on the rules for settling their differences. With the clock ticking on deadlines set in Kyoto, a breakdown in Argentina could strip the process of its political momentum and delay action on climate for years. The treaty is on shaky political ground in a number of world capitals. As of last month, only 55 countries have signed the accord and only one -- Fiji -- has ratified it.

One concern is that modernising countries such as China and India are on their way towards eclipsing the developed world as the biggest polluters, and any climate strategy that excludes them would fail in the long run.

CIPRA
The eight nations that share the European Alps since 1989 are setting up an Alpine Convention, an international contract, which aims to establish joint principles and rules for the sustainable development and the protection for this fragile and in some parts seriously charged mountain ecosystem. The Frame Convention was signed in 1991 and entered into force in 1995. Seven Protocols are now signed - three recently on October 16th at the 4th Alpine Conference in Bled/Slovenia.

If you wish to know more about it - visit the homepage of CIPRA. You will find the texts of the Convention and the signed Protocols (not quite complete) as well as the position of the NGO's on the topic in four languages (French, German, Italian and Slovenian) under "Alpenkonvention": The results of the 4th Alpine Conference can be found under "aktuell".

GLOBAL WARMING IMPACTS ON THE ARCTIC
Alaska is thawing, and much of northern Russia and Canada with it, and many scientists say that the warming of these cold regions is one of the most telling signals that the planet's climate is changing. Experts have long said that in an era of global warming, this bellwether region should warm more and faster than the Earth as a whole, and that is just how things are turning out.

Scientists employing laser instruments have confirmed that many of Alaska's hundreds of glaciers are retreating. The warmer atmosphere, which holds more moisture, has produced more snow to feed the glaciers, but longer, warmer summers have in many cases melted them even faster than the heavier snows can build them up. The region's permafrost, ground that is perpetually frozen, is thawing in Alaska's interior, and pockets of underground ice trapped in the frost are melting with it. Over thousands of kilometres, big patches of forest are drowning and turning grey as the ground sinks under them and swamp water floods them. Here and there, deep holes have opened in the earth. Roadside power poles, destabilised by the melting, tilt at crazy angles. So do trees, creating a phenomenon known as drunken forest.

The intermittent character of the land's subsidence -- the permafrost comes in patches in most of the state, and not every patch has ice pockets -- wreaks havoc on paved roads. Many stretches of highway are like ocean swells overlaid with irregular breaks and cracks, and driving on them safely often requires vigilance.

Along the Fairbanks-to-Valdez stretch, entire mountainsides of spruce forest, prime timberland that used to be part of the magnificent taiga, the vast boreal forest of conifers that rings the world's northern latitudes, are dead and grey. The trees have been weakened by several climate-related stresses, then killed by spruce bark beetles whose population, scientists say, has exploded in the higher temperatures. "It has moved into high gear in the last six or seven years," said Dr. Glenn Juday, a forest ecologist at the University of Alaska. "It's just rolling through the forest."

About the magnitude of the warming, there is little doubt. While the average surface temperature of the globe has risen over the last century by 0.5 degrees Celsius or a little more, scientists at the University of Alaska and elsewhere say that it has increased over the last 30 years by as much as 3 degrees in Alaska, Siberia and northwestern Canada. The warming has been most pronounced in winter.

Scientists are not certain how much of the regional warming relates to over-all warming of the globe, if any. Some of it, they say, is clearly the result of a change in prevailing patterns of atmospheric circulation, beginning in the mid-1970s, which generally redirected the flow of warm air from the Pacific toward Alaska. But researchers like Dr. Gunter Weller, of the University of Alaska in Fairbanks, an expert on climate change, point out that big areas of northern Russia not affected by the circulation change have warmed as much as Alaska. Moreover, say other experts, it is possible that global warming had something to do with the shift in circulation.

The scientists say that Alaska and other far northern continental regions should warm about twice as much as the average for the globe. There are two main reasons lie behind this: As ice and snow melt, less heat is reflected off the land, amplifying the warming. And at these latitudes, the atmosphere is more stable in winter and spring. This confines more heat to its lower layers.

At the moment, the warming is perhaps most evident in its effects on forests, permafrost and glaciers.

A few kilometres southwest of Fairbanks is the Bonanza Creek Experimental Forest, a long-term ecological research reservation. A vintage old-growth forest of white spruce not far from the Arctic Circle, it is in the middle of the taiga. Normally, the snows at that latitude are light and fluffy. But recently they have become heavier, apparently a result of the changing climate. The weight of two especially heavy snowfalls in the late 1980s and early 1990s broke off the tops of trees. "There was an incredible outbreak of insects following that," and they attacked the trees, Juday said.

In a broad swath stretching for 500 or 600 kilometres from the Kenai Peninsula south of Anchorage past the Chugach Mountains parts of the landscape have turned red (freshly killed) or grey (long dead). Spruce bark beetles are the killers, and they are "basically eliminating the forest canopy," said Jerry Boughton, who heads the U.S. Forest Service's regional forest health program, based in Anchorage. Scientists estimate that a third to half of Alaska's white spruce have died in the last 15 years.

Several factors have combined to produce this ecological holocaust, said Boughton, not least the fact that the forest is older, and therefore more vulnerable to insect attack. "But certainly, the warming has created a better environment for the bark beetle to expand," he said. In fact, mainstream scientists say, that is how the predicted global warming would often make itself felt: by exacerbating stresses of many kinds.

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