NORTH CASCADE GLACIER CLIMATE PROJECT
 


Mauri S. Pelto, Director  Founded 1983
Nichols College, Dudley, MA    Peltoms@nichols.edu

Recent Global Glacier Retreat Overview

In historic times, glaciers grew during the Little Ice Age, a cool period from about 1550 to 1850. Subsequently, until about 1940, glaciers around the world retreated as climate warmed. Glacier recession declined and reversed, in many cases, from 1950 to 1980 as a slight global cooling occurred. Since 1980, glacier retreat has become increasingly rapid and ubiquitous, so much so that it has threatened the existence of many of the glaciers of the world [1]. This process has increased markedly since 1995, leading to such bizarre steps as covering sections of Austrian alpine glaciers with plastic to retard melting. The World Glacier Monitoring Service [2] has noted 17  consecutive years of negative mass balances, that is volume losses.  If a business had 17 consecutive losing years they would be bankrupt.  This can lead to the disappearance of a glacier as seen below with Milk Lake Glacier and Lewis Glacier, North Cascades, Washington.  Which melted away between 1988 and 1995, creating Milk Lake.

Milk Lake in 2006, the glacier now entirely gone.

Milk Lake Glacier in 1988 clinging to the slopes above the greenish lake.
Lewis Glacier in 1988 as the last relict ice is melting away Former Lewis Glacier basin in 2006
 

The recession of mountain glaciers, has been used to provide qualitative support to the rise in global temperatures since the late 19th century [3]. Many glaciers are being lost to melting further raising concerns about future local water resources in these glacierized areas. Glaciers are the perfect summer water supply in alpine regions providing the highest runoff during warm dry periods when other water sources are at a minimum.  The smaller the glacier area to melt, the less the runoff, the greater the change in alpine streamflow and the higher the stress on man and aquatic users of this resource.  The result of glacier loss will be reduced summer runoff providing fewer resources for hydropower in Europe, hydropower and irrigation in the Himalaya, Andes and Western North America. The Lewis Glacier, North Cascades pictured at right after melting away in 1990, reducing its August streamflow by 40%.

Glaciers respond to climate in an attempt to achieve equilibrium. A glacier consists of an accumulation zone where accumulation persists through the summer, and an ablation zone where snowcover is seasonal and melting dominates. To be sustained a glacier must have a consistent accumulation zone.  A glacier advances due to a climate cooling/snowfall increase that causes positive mass balance.  This advance increases the glaciers area at low elevation where ablation is highest, returning the glacier to equilibrium.  A climate warming/snowfall decrease leads to negative mass balances and glacier retreat.  To reestablish equilibrium a retreating glacier must lose enough of its highest melting (ablating) sections, usually at the lowest elevations, so that accumulation in the accumulation zone once again balances ablation, reestablishing equilibrium..  If a glacier cannot retreat to a point where equilibrium is established, it is in disequilibrium with the climate system. A glacier that is in disequilibrium with present climate will melt away with a continuation of this climate.   A glacier that is significantly thinning in the accumulation zone does not have a consistent accumulation and will disappear.  The thinning is evident by bedrock being exposed in the accumulation area and thinning of  the glacier margin in the accumulation zone.  Thus, we can have retreat at the head of the glacier not just at the terminus of the glacier.  The chart at left indicates that global mass balance ( Data from World Glacier Monitoring Service [4]) is trending more negatively today even as glaciers retreat rapidly.  Since glacier termini take a few years to respond to climate change, they will continue to retreat in the foreseeable future regardless of climate.  With a continuation of the current climate retreat will continue as the glacier mass balances indicate the glaciers are not approaching equilibrium.

For another detailed review of glacier retreat also see Glacier Retreat at Wikipedia

For detailed analysis of selected individual glaciers and their retreat histories Glacier Change

North America

Cascade Range

The Cascade Range of western North America extends from southern British Columbia in Canada to northern California. Excepting Alaska, about half of the glacial area in the U.S. is contained in the more than 700 glaciers in the North Cascades, a portion of the range between the Canadian border and I-90 in central Washington. These glaciers store as much water as that contained in the lakes and reservoirs in the rest of the state and provide much of the stream and river flow in the dry summer months, some 870,000 m³. As recently as 1975, many North Cascade glaciers were advancing due to cooler/wet weather during the 1944-1976 period. However, by 1987, all North Cascade glaciers were retreating. However, since 1976 these glaciers have receded rapidly. Between 1984 and 2007, they have lost an average more than 12 m in thickness and 20 to 40% of their volume.[10].  The Easton Glacier pictured below has retreated 290 m since 1985.

Easton Glacier began retreating in 1985 and through 2008 has retreated 290 m, and is currently retreating at a rate of 15 meters/year  

Lyall Glacier, North Cascades with 1966 map outline and SPOT satellite image overlay from 2005.  A new lake has formed and the glacier is gone.

 

This recession is widespread. All 47 monitored glaciers are receding and five have disappeared completely. The White Chuck Glacier (near Glacier Peak) is a particularly dramatic example. It shrank from 3.1 km2 in 1958 to 0.9 km2 in 2002. The Boulder Glacier on the southeast flank of Mount Baker retreated 450 m from 1987 to 2005 leaving unvegetated terrain behind. This retreat has occurred during a period of less winter snowfall and higher summer temperatures. Winter snowpack has declined 25% since 1946 and summer temperatures have risen 1.2 degrees Fahrenheit (0.7 °C) during the same period. Four glaciers have been observed to disappear since 1985; Spider Glacier, Lewis Glacier, Milk Lake Glacier and David Glacier. Currently most North Cascade glaciers are in disequilibrium, meaning they cannot retreat to a point of new equilibrium and can only melt away with the present climate.[11] [12].  Below is the Whitechuck Glacier viewed from the same location in glacier gap in 1973 and in 2005.  This glacier has lost 80% of its area in the last century.  The result is less late summer runoff in the Whitechuck River.

Rocky Mountains

In the Canadian Rockies, the Athabasca Glacier, one of the outlet glaciers of the 325 km² Columbia Icefield, has retreated 1500 m since the late 19th century. This retreat has become more rapid after 1980, following a period of slow retreat from 1950-1980. The Peyto Glacier, covering an area of about 12 km², retreated rapidly during the first half of the 20th century, stabilized by 1966 and resumed shrinking in 1976. [13] Illecillewaet Glacier in British Columbia's Glacier National Park (Canada) has retreated 2000 m since first photographed in 1887 below. 


Illecillewaet Glacier (Great Glacier), circa 1898.
Photo Credit: Parks Canada Collection.
 Lines mark the extent of ice, Illecillewaet Glacier, Glacier National Park.
Photo Credit: Dr. Dan McCarthy, Brock University

On the sheltered slopes of the highest peaks of Glacier National Park, most glaciers are diminishing rapidly. The area of each glacier has been mapped by the National Park Service and the U.S. Geological Survey. [14] Every glacier has retreated notably in the last 140 years. The larger glaciers are now approximately a third of their size when first studied in 1850, and numerous smaller glaciers have disappeared completely. Only 27% of the 99 km² area of Glacier National Park covered by glaciers in 1850 remained by 1993. An increase of approximately 1 degree Celsius (2 °F) in average summer temperatures is reflected in reduced glacier sizes. A computer model indicates that present rates of increasing warming will eliminate all glaciers in Glacier National Park by 2030. This proposed time table for disappearance is too fast.

Glacier National Park’s glaciers have been the focus of long term mapping changes of Sperry Glacier and Grinnell Glacier  and areal extent change mapping of many of the larger glaciers in the Park [14].  Mass balance and ice surface elevation mapping have not been completed; hence satellite imagery must be utilized to assess glacier response.  In the current assessment 10 of the 15 glaciers are experiencing a disequilibrium response and will disappear, the other five have been shrinking little.  Blackfoot and Harrison Glacier are the two largest glaciers and show minimal changes in the accumulation zone.    Both glaciers continue to retreat with the main termini retreating approximately 100-120 m since 1966.   Three smaller glaciers Ahern, Old Sun and Weasal Collar occupy avalanche fed cirques and continue to maintain significant snowcover even in warm summers such as 2005 and 2007.  The result has been minimal changes in these glaciers. Exposure of significant new bed rock in the accumulation zone was evident on Sperry, Baby, Ipasha, Whitecrow and Shepard Glacier (Figure 10).  Extensive marginal retreat in the accumulation zone is evident on Grinnell, Sperry, Jackson, Kintla, Baby, Whitecrow, Sexton and Shephard Glacier.  Areal extent losses of these glaciers ranged from 20 to 100% during the 1966-2007 period.   Dixon, Baby and Whitecrow are no longer glaciers with no evident ice mass more than 0.01 km2, Shephard Glacier is nearly gone. Many of the 34 glaciers identified on the 1966 USGS maps  [14], have disappeared, yet a number of glaciers have been experiencing an equilibrium response.  Hall and Fagre (2003) utilized a model to construct the future of glaciers in the Blackfoot-Jackson watershed, and determined that all would be gone by 2030 with continued substantial warming, but not with limited additional warming.  Based on the slow recession and equilibrium response of Blackfoot and Harrison Glacier to recent climate over the last 40 years these two glaciers are not going to disappear within the next 30 years.  There are at least five glaciers in the park that have retreated slowly in the last 40 years and still have healthy accumulation zones, indicating they are not on the verge of disappearing.  As Andrew Fountain  has noted as glaciers shrink to a small size they can be tough to eliminate if they have an accumulation area.

 

Figure 9.  Harrison Glacier, Glacier National Park, the glacier margin in 2005 and orange line showing the 1966 margin map overlay on this SPOT satellite image.  No evident change in the accumulation zone indicates an equilibrium response.

  

Figure 10.  Shephard Glacier, Glacier National Park, the glacier margin in 2005 and orange line showing the 1966 margin map overlay on this SPOT satellite image.  Much of the accumulation zone of the glacier is now gone indicating a disequilibrium response.

The semiarid climate of Wyoming still manages to support about a dozen small glaciers within Grand Teton National Park which all show evidence of recession over the past 50 years. One of the more easily reached of the glaciers in the Park known as "Schoolroom Glacier" is expected to be gone in 25 years. [15] Research between 1950 and 1999 demonstrated that the glaciers in Bridger-Teton National Forest and Shoshone National Forest in the Wind River Range shrank by over a third of their size over that period. Photographs indicate that the glaciers today are only half the size as when first photographed in the late 1890's. Research also indicates that the glacial retreat was proportionately greater in the 1990s than in any other decade of the last 100 years. [16]  Glaciers in the region have experienced ongoing negative balances and glacier shrinkage.  Examination of Dinwoody and Gannett Glacier indicated relatively little change in terminus position or areal extent from 1958-1983 [16].  Since 1983 retreat rates have again accelerated on these two glaciers.  There is are no recent field observations of mass balance, glacier thickness or glacier extent change in the Wind River Range, and satellite imagery is the only means to assess glacier response in the region to climate change over the last 40 years.  Of the 15 glacier examined six have experienced insignificant change in glacier margin and ice thickness.  Gannett and Dinwoody Glacier are the two largest glaciers in the range and despite significant terminus retreat, the accumulation zones remain unchanged.  On Fremont Glacier  the change in areal extent is 11%.  Of the nine glaciers in disequilibrium J, Twins, Grasshopper, Minor, Heap Steep, Mammoth and Lower Fremont Glacier exhibit significant new bedrock exposure within the accumulation zone.  Marginal retreat in the accumulation zone is evident on Baby, J, Twins, Grasshopper, Minor , Heap Steep, Helen and Lower Fremont Glacier.   Knife Point Glacier has lost 31 % of its area since 1966, but all the change is in the terminus area of the glacier, 280 m of retreat, and one small tributary chute on its northern margin.  Grasshopper Glacier has experienced 640 m of retreat and 27% reduction in areal extent, with most of the reduction in the accumulation zone.  These examples indicate the difficulty in using only terminus change or areal extent change in determining equilibrium response. 

 

Figure 7.  Fremont Glacier, Wind River Range, the glacier margin in 2005 and orange line showing the region where the margin is not the same from the 1966 map overlay on this SPOT satellite image.  No evident change in the accumulation zone indicates an equilibrium response.

 

  

Figure 8.  Minor Glacier, Wind River Range, the glacier margin in 2005 and orange line showing the glacier margin from the 1966 map overlay on this SPOT satellite image.  Much of the accumulation zone of the glacier is now gone indicating a disequilibrium response.

Alaska

Valdez Glacier has thinned 300 feet over the last century and the unvegetated brown areas near the glacial margins have been exposed due to the glacier thinning and retreating over the last 2 decades of the 20th century

Alaska is home to thousands of glaciers, most still unnamed. One of the more famous glaciers is Columbia Glacierr, near Valdez. It was a course change to avoid icebergs from this glacier that ultimately resulted in the 1989 Exxon Valdez oil spill. Columbia Glacier, which terminates in a grounded calving margin in Prince William Sound in central coastal Alaska, has retreated 15 km in the last 25 years. The Valdez Glacier pictured is in the same area, does not calve but has retreated throughout the century. Calving glaciers can retreat faster via calving icebergs, than glaciers that do end in a calving front.

The Juneau Icefield Research Program has monitored the outlet glaciers of the Juneau Icefield since 1946. On the west side of the icefield from 1946-2005 the terminus of the Mendenhall Glacier, which flows into suburban Juneau has retreated 580 m, Herbert Glacier five miles north has retreated 910 m, Eagle Glacier another five miles north has retreated 1090 m. On the south side of the icefield Norris Glacier retreated 1740 m the East Twin Glacier 720 m and the West win Glacier 570 m. Only the Taku Glacier has advanced. This glacier was advancing in 1890 when viewed by John Muir and had a large calving front. By 1963 the glacier had advanced 3.7 miles. In 1948 the fjord had filled in and the glacier no longer calved. It was just like finishing payment on a home mortgage, the glacier no longer lost icebergs and was able to continue its advance of a further 0.5 miles. In 2005 the glacier is only 0.93 miles from reaching Taku Point and blocking Taku Inlet, and is advancing at a rate of 17 m/year. The mass balance was very positive for the 1946-1988 period fueling the advance, however, since 1988 the mass balance has been slightly negative which should in the future slow the advance of this mighty glacier. [17] Glacier retreat is driven by negative mass balance. Long term mass balance records from Lemon Creek Glacier show declining mass balance with time [18]. The mean annual balance for this glacier was –0.23 m/yr 1957-1976. Mean annual balance has been increasingly negative since 1977, averaging -0.78 m/yr. The record is particularly negative since 1990, -1.04 m/yr, indicating even more rapid glacier retreat. Repeat glacier altimetry for 67 Alaska glaciers find rates of thinning have increased by more than a factor of two when comparing the periods from 1950 to 1995 (-0.7 m/yr) and 1995 to 2001 (-1.8 m/yr). [19] This is a systemic trend with loss in mass equaling loss in thickness, which leads to increasing retreat.

Beginning in the 1990's, using a laser measuring device mounted on the underside of an airplane, researchers compared glacier altitude differences with ground survey maps created in the 1950's. 85% of the glaciers flown over stretching from Alaska to Washington state had a reduction in altitude, and therefore, a thinning of the glacial mass. Further flights since then indicate that this thinning is accelerating and is now double what it was in the 40 years before the mid 1990's. [20] In Denali National Park the terminus of the Toklat Glacier is retreating 24 m/year and the Cantwell Glacier 10 m/year. There are many surging glacier in the Park and in Alaska whose terminus responses are part due to climate and part due to surging behavior.

Europe: Alps

The World Glacier Monitoring Service reports on changes in the terminus position of glaciers from around the world every 5 years. [4], 103 of 110 glaciers examined in Switzerland were retreating. In 2005 for the first time ever all glaciers examined in Switzerland were retreating. Similarily, in Austria 95 of 99 glaciers were retreating, in Italy all 69 observed glaciers were in retreat and in France all 6 were retreating. French glaciers experienced a sharp retreat in the years 1942-53 followed by advances up to 1980, then further retreat from 1982. As an example the Argentière Glacier and Blanc Glacier have receded by 1150 and 1400 meters respectively since 1870. The largest glacier Chamonix remember the Bossons Glacier coming almost as far as the road. It has lost 1200 meters in length. This shrinking is not without risks. Glacial lakes have formed at the foot of the Mer de Glace. The lakes are held behind moraine dams. If the natural dams that hold this meltwater back break, it could cause widespread flooding in the valley below. In 1892 the lake of the Glacier de Tête Rousse burst emptying some 200,000 m33 of water and killing 200 people in Saint Gervais. Ski areas in Austria have covered areas of the Stubai and Pitztal Glacier with plastic wrap to retard melting of the glaciers that their ski areas utilize. Since 1980, 20% of the area of Swiss glaciers has been lost. The Grosser Aletsch Glacier is the largest glacier in Switzerland and has retreated 2600 m since 1880. The rate of retreat has increased after 1980, with 800 m or 30% of the total retreat occuring in the last 25 years [5].  In the Italian Alps the percentage of retreating glaciers has increased from 34% in 1980 to 96% in 1999, and has remained above 95% through 2005.[6]. 

Scandinavia

In the Kebnekaise Mountains of Northern Sweden of sixteen glaciers examined from 1990-2001, 14 are retreating, one is advancing and one is stable [7] During the 20th century glaciers in Norway retreated as did glaciers in other parts of the world at the end of the Little Ice Age. Most Norwegian glaciers did have brief periods of advance around 1910, 1925 and in the 1990's. In the 1990s 11 of 25 Norwegian glaciers observed advanced due to several winters in a row with precipitation above normal. Since 2000, Norwegian glaciers have decreased significantly. This resulted from several consecutive years of little winter precipitation, and record-warm summers in 2002 and 2003. By 2005 Only 1 of the 25 glaciers was advancing, two were stationary and 22 were retreating. Engabreen has retreated 179 meters since 1999, while Brenndalsbreen and Rembesdalsskåka have retreated 116 and 206 meters since 2000. At Briksdalsbreen the glacier retreated 96 m in 2004, this is the largest annual retreat recorded since monitoring started in 1900. Since 1999, the glacier has retreated 176 meters. [8]

Iceland

The Breidamerkurjökull, one of the glaciers that is an outlet of the Vatnajökull, the largest ice cap in Europe, has receded by as much as 2 km since 1973. A hundred years ago Breidamerkurjokull, extended to within 250 m of the ocean, Today, Breidamerkurjokull's terminus is three kilometers from the ocean. The glacier retreat has exposed a rapidly expanding lagoon, which is filled with icebergs calved from its front. The lagoon is 350 feet deep and has nearly doubled its size during the past decade. All but one of the Vatnajokull outlet glaciers, roughly 40 named glaciers in all, are receding as of 2000. [9]

Greenland

Despite their proximity and importance to human populations, the mountain and valley glaciers of temperate latitudes amount to a small fraction of glacial ice on the earth. About 99% is in the great ice sheets of polar and subpolar Antarctica and Greenland. These continuous continental-scale ice sheets, 3 kilometers or more in thickness, cap the polar and subpolar land masses. Like rivers flowing from an enormous lake, numerous outlet glaciers transport ice from the margins of the ice sheet to the ocean.

Glacier recession has been observed in these outlet glaciers. This can increase the ice flow rate and destabilize the mass balance of the ice sheet that is their source. In Greenland the last five years has brought retreat to several very large glaciers that had long been stable. Three glaciers that have been researched, Helheim, Jakobshavns and Kangerdlugssuaq Glaciers, jointly drain more than 16% of the Greenland Ice Sheet. In the case of Helheim Glacier, researchers used satellite images to determine the movement and retreat of the glacier. Satellite images and aerial photographs from the 1950s and 1970s show that the front of the glacier has remained in the same place for decades. But in 2001 it began retreating rapidly, retreating four and a half miles (7.2 km) between 2001 and 2005. It has also accelerated from 20 m/day to 32 m/day. [21]

Jakobshavns Isbrae in west Greenland, a major outlet glacier of the Greenland Ice Sheet, is generally considered the fastest moving glacier in the world. It had been moving continuously at speeds of over 24 m/day with a stable terminus since at least 1950. In 2002, the 12 km long floating terminus entered a phase of rapid retreat. The ice front started to break up and the floating terminus disintegrated. The glacier accelerated to over 30 m/day.[22]

The rapid thinning, acceleration and retreat of these three large glaciers in close association with one another suggests a common triggering mechanism.   Since the acceleration is not seasonal and because it began at the ice front and propagated inland it cannot be due to the commonly cited meltwater lubrication of the ice sheet base.  Instead the acceleration is most pronounced in marine terminating outlet glaciers.  These glaciers have calving fronts.  The acceleration is year around.  Thinning at the terminus increases buoyancy reducing friction and back forces.  This allows acceleration [22a]. 

Africa

With almost the entire continent of Africa located in the temperate zone, the few places that glaciers do exist are restricted to two isolated peaks and the Ruwenzori Range. What has been popularized as the "snows of Kilimanjaro" on Mount Kilimanjaro, which at 19,340 feet (5,895 m) is the highest peak on the continent, may be a thing of the past in less than 30 years. Since 1912, the glacier cover on the summit of Kilimanjaro has apparently retreated 75 % and just from the period of 1984 to 1998, one section of glacier receded 300 meters vertically. A report from March 2005 indicated that there is almost no remaining glacial ice on the mountain and it is the first time much of the surface of the summit has been observable in 11,000 years. [23] Observers believe that there will be no more glacial ice on the summit of Kilimanjaro by the years 2015 to 2025. Mount Kenya which at 17,057 feet (5,199 m) is the second tallest mountain on the continent and has up to a dozen small glaciers has shown a loss of area at least 45 % since the middle part of the 20th century.

The Ruwenzori Range which rise to 16,761 ft (5,109 m), are to the west of the isolated peaks of Kilimanjaro and Kenya. These mountains are oftentimes cloud capped, making satellite imagery difficult and the political dynamics of the surrounding region have made access complicated at best over the past few decades. However, photographic evidence demostrates a marked reduction in glacially covered regions over the past century. It is expected that due to their closer distance to the heavy moisture of the Congo region, the glaciers in the Ruwenzori Range may recede at a slower rate than either Kilimanjaro or Kenya.

Himalayas

Nasa image shows the formation of numerous glacial lakes at the termini of receding glaciers in Bhutan Himalaya.

A WWF report, An Overview of Glaciers, Glacier Retreat and Subsequent Impacts in Nepal, India and China (2005), [24] concluded that 67% of Himalyan glaciers are retreating rapidly. Though the glaciers are rapidly retreating, many are still quite large and are not in danger of disappearing before 2050.  In examining 612 glaciers in China, 50% were found to be retreating in 1970 and 95% after 1990. Some of the more famous glaciers in the area indicate the trend.  Rongbuk Glacier, draining the north side of Mount Everest into Tibet, has been retreating 20 m/yr. Gangotri Glacier in India has been retreating 30 m/yr in the early 2000s and has retreated 1 km since the 1970's.  Gangotri is the head of the Bhagirahti River and is still 30 km long and has an area of 280 km2.  The rate of melting is substantial but this glacier is not in danger of disappearing any time soon.

Oceania

The vast moraine wall is evidence of the retreat of the Mueller glacier, which is covered in rubble. In the distance a further lake and moraine wall show where the glacier has retreated

In New Zealand the mountain glaciers have been in a general recession since 1890, with an acceleration of this recession after 1920. Most of the glaciers have been reduced in size and the accumulation zone had a corresponding rise to higher elevations as the 20th century progressed. During the period of 1971 to 1975, Ivory Glacier was reduced 30 m at the glacial terminus and the loss of ice during the period was 13.9 x 106 m3. 26 % of the surface area of the glacier was lost over the same period. Since 1980, numerous small glacial lakes were created behind the terminal moraines of several glaciers and the glacier thickness has been reduced. Glaciers such as Classen, Godley and Douglas now all have proglacial lakes below their new terminal locations due to the glacial retreat over the past 20 years. Satellite imagery indicates that these lakes are expanding in area as well.

Several glaciers, notably the much visited Foxx and Franz Josef Glaciers, have periodically advanced (especially during the 1990s) but the scale of these advances is small compared to 20th century retreat. These rapid flowing large glaciers with steep trunks have been very reactive to small mass-balance changes. A few years of favorable conditions are rapidly echoed in a corresponding advance, followed equally rapidly by renewed retreat when those favorable conditions end. [25]

USGS Puncak Jaya glaciers 1936 and 1972. Left to right: Northwall Firn, Meren Glacier, and Carstensz Glacier. USGS

On the large island of New Guineaa, there is photographic evidence of massive glacier recession since the region was first extensively photographed in the early 1930s. Due to the location of the island within the tropical zone, there is little to no seasonal variation in temperature. The tropical location has a predictably steady level of rain and snowfall, as well as cloud cover year round and there has been no noticeable change in the level of moisture which has fallen during the 20th century. Therefore, the glacial retreat evidenced can only be attributed to a general warming trend. The 7 km glacial cap on the mountain known as Puncak Jaya is the largest on the island, and has retreated from one larger mass into several smaller glacial bodies since 1936. Of these glaciers, between 1973 and 1976, the Meren Glacier retreated 200 m and the Carstensz Glacier retreated 50 m over the three year period. The third larger area that was once part of the icecap known as the Northwall Firn, had split into several smaller glaciers by 1972. One small icecap known to exist on the summit of Puncak Trikora completely disappeared sometime between 1939 and 1962. [26] All the glaciers on the island are located within the country of Indonesia and separatist rebels in the area led the Indonesian Government to close off most access to the region in 1995. However, research presented in 2004 of imagery from the IKONOS satellite of the New Guinean glaciers provided a dramatic update. The imagery indicated that between the years 2000 and 2002, the East Northwall Firn had lost 4.5%, the West Northwall Firn 19.4% and the Carstensz 6.8% of their glacial mass in only those two years. The presentation went on to state that "Sometime between 1994 and 2000 the Meren Glacier appears to have disappeared." [[27].  The end result is a decline in glacier area from 18.8 to 2.1 square kilometers.  

Andes

show alarming recession. More than 80 % of all glacial ice in the northern Andes is concentrated on the highest peaks in smaller glaciers of one km² in size. Chacaltaya Glacier in Bolivia and Antizana Glacier in Ecuador were examined between 1992 and 1998 showed that between 0.6 and 1.4 m of water was lost per year on each glacier. Chacaltaya Glacier lost two-thirds of its volume and 40 % of its thickness over the same period and it is expected that by 2010 to 2015, Chacaltaya Glacier will no longer exist. Chacaltaya Glacier is only 10 % of its size when first examined in 1940. The evidence also supported findings that since the mid 1980's, the rate of recession for both glaciers has also been increasing. [28]

Further south in Peruu, the Andes are much taller overall and there are 722 glaciers covering an area of 723.4 km². Research in this region of the Andes is less conclusive but indicate that between 1977 and 1983, a glacial recession of 7 % occurred. [29][30]]

A large region of population surrounding the central Andes of Argentina and Chile reside in arid areas that are dependant on water supplies from melting glaciers. The water from the glaciers also supply rivers that have in some cases been dammed for hydroelectric power. Some researchers think that by 2030, many of the large ice caps on the highest Andes will be gone, if current trends continue. In Patagonia on the southern tip of the continent, the large ice caps have been shown to have retreated a full kilometer since the early 1990s and 10 km since the late 1800s. It has also been claimed that Patagonia glaciers are receding at a faster rate than any other region in the world. [31]
 

Antarctica

The collapsing Larsen B Ice Shelf is similar in area to the U.S. state of Rhode Island.

The most dramatic glacier recession is the loss of large sections of the Larsen Ice Shelf on the Antarctic Peninsula. The collapse has been due to warmer melt season temperatures leading to surface melting and the formation of shallow ponds of water on the ice shelf. The Larsen Ice Shelf lost 2,500 square kilometers from 1995 to 2001. Then, a total of about 3,250 km2 of shelf area disintegrated in a 35-day period beginning on 31 January 2002. The ice sheet is now 40 percent the size of its previous minimum stable extent. [32].  The Wilkins Ice Shelf has experienced substantial ice losses in 2008. [35]

An examination of 244 marine glacier fronts on the Antarctic Peninsula and associated islands over the past 61 years indicates that 87% have retreated.  A clear boundary between mean advance and retreat has migrated progressively southward.[34]

Pine Island Glacier, which flows into the Amundsen Sea thinned 3.5 ± 0.9 meters per year and retreated five kilometers in 3.8 years. The end of the glacier is a floating ice shelf. The location where the glacier becomes afloat is retreating 1.2 km/year. This glacier drains a substantial portion of the West Antarctic Ice Sheet and has been called the weak underbelly of this ice sheet. [[33]. Dakshin Gangotri Glacier is a small outlet glacier of the continental ice sheet. It receded at a rate of 7 m/decade from 1983 to 2002.