KAZALCI OKOLJA

You are here

Key message
Bad

The shrinking of the Triglav glacier progressed during the 1990’s. The increasingly rapid thinning of the ice sheet caused individual rock formations to appear in the middle of the glacier, finally cutting it into two completely separate parts in 1992. Shrinking and disintegration of the Triglav glacier has not ceased; the process has only been brought to a standstill during years with above-average snow cover in the late spring.


The indicator shows changes in surface area and volume of the Triglav glacier. A glacier is a perennial mass of ice on the Earth’s surface, which moves downhill under its own weight in response to gravitational force. A glacier forms above the snow level, in locations where the mass accumulation of snow and ice exceeds ablation over many years. The snow is gradually transformed into ice glacier, which moves downhill reaching far down below the snow line. The key factors of ablation are: sun radiation, air temperature, precipitation and wind.

Changes in glacier volume and extent are an illustrative indicator of climate changes. During the last decade, the trend of rapid glacier retreat has been characteristic of all Alpine glaciers. In Slovenia, there are two glaciers: the Triglav glacier and the Skuta glacier. Due to their extreme southeastern position and low elevation above sea level, both are exceptionally sensitive to climate changes. Since the above-mentioned Slovenian glaciers are small, their relative shrinkage in respect to their present extent and volume is greater than is the case with other Alpine glaciers.


Charts

Figure PS05-1: Changes in the Triglav glacier surface area
Sources: 

Anton Melik Geographical Institute at the Science and Research Centre of the Slovenian Academy of Sciences and Arts, 2007

Show data
1992 1995 1999 2003 2005 2007 2008 2009 2010
surface ha 4.3 3 1.1 0.7 1.1 0.6 1.1 2.9 2.5
Figure PS05-2: Changes in the Triglav glacier volume
Sources: 

Anton Melik Geographical Institute at the Science and Research Centre of the Slovenian Academy of Sciences and Arts, 2009

Show data
1992 1999 2005 2008
volume m3 400 60 20 10
Figure PS05-3: Extent of the Triglav glacier by individual year
Sources: 

Anton Melik Geographical Institute at the Science and Research Centre of the Slovenian Academy of Sciences and Arts, 2006

Figure PS05-4: Povprečna temperatura talilne sezone na Kredarici po obdobjih
Sources: 

Agencija RS za okolje, 2011

Show data
1961-1970 1971-1980 1981-1990 1991-2000 2001-2010
Average temperature of the melting season oC 3.3 2.7 3.7 3.8 4.2
Figure PS05-5: Kumulativna specifična masna bilanca izbranih ledenikov v Evropi za obdobje 1946-2008
Sources: 

World Glacier Monitoring Service, 2010

Show data
1946 1947 1948 1949 1950 1951 1952 1953 1954 1955
Careser (IT) mm w.e.
Gries (CH) mm w.e.
Hintereis (AT) mm w.e. 0 -540 -826 -750
Saint Sorlin (FR) mm w.e.
Sarennes (FR) mm w.e. 0 -2990 -4610 -4410 -6030 -6670 -7220 -6560
Vernagt (AT) mm w.e.
Storglaciaeren (SE) mm w.e. -1130 -3190 -3190 -2290 -3580 -4230 -4390 -5200 -6170 -6330
Nigardsbreen (NO) mm w.e.
Austre Broeggerbreen (NO) mm w.e.
Aalfotbreen (NO) mm w.e.
Hofsjokull N (IS) mm w.e.
Maladeta (ES) mm w.e.
1956 1957 1958 1959 1960 1961 1962 1963 1964 1965
Careser (IT) mm w.e.
Gries (CH) mm w.e. 0 -984 -1164 -1852 -1407
Hintereis (AT) mm w.e. -1025 -1214 -2195 -2958 -3020 -3225 -3921 -4524 -5768 -4843
Saint Sorlin (FR) mm w.e. 0 -360 -330 -1540 -1870 -1760 -2860 -2590 -4240 -3780
Sarennes (FR) mm w.e. -7160 -7680 -8350 -9610 -9490 -9880 -10790 -10600 -12430 -12400
Vernagt (AT) mm w.e. 0 751
Storglaciaeren (SE) mm w.e. -6810 -7130 -7780 -8750 -10360 -11460 -11140 -11330 -10840 -10410
Nigardsbreen (NO) mm w.e. 0 2250 2030 2980 3890
Austre Broeggerbreen (NO) mm w.e.
Aalfotbreen (NO) mm w.e. 0 -1100 -820 -340
Hofsjokull N (IS) mm w.e.
Maladeta (ES) mm w.e.
1966 1967 1968 1969 1970 1971 1972 1973 1974 1975
Careser (IT) mm w.e. 0 -390 -130 -130 -760 -1410 -1010 -2290 -2610 -2440
Gries (CH) mm w.e. -1764 -1735 -1356 -623 -1381 -1908 -1500 -2595 -2773 -2395
Hintereis (AT) mm w.e. -4499 -4479 -4141 -4572 -5124 -5724 -5798 -7027 -6972 -6907
Saint Sorlin (FR) mm w.e. -3080 -3540 -2730 -2290 -2160 -3010 -3250 -4010 -4830 -4550
Sarennes (FR) mm w.e. -11980 -12390 -12050 -12410 -12820 -13920 -14290 -15160 -16760 -16650
Vernagt (AT) mm w.e. 1383 1466 1767 1460 1236 812 949 489 719 890
Storglaciaeren (SE) mm w.e. -10940 -11170 -11270 -12310 -13830 -14020 -15070 -15020 -15360 -14190
Nigardsbreen (NO) mm w.e. 2970 5130 5350 4040 3480 4300 4160 5260 5740 6010
Austre Broeggerbreen (NO) mm w.e. 0 -650 -750 -1680 -2220 -2800 -3110 -3190 -4110 -4420
Aalfotbreen (NO) mm w.e. -1950 -670 280 -1890 -3120 -2180 -2290 -110 920 2130
Hofsjokull N (IS) mm w.e.
Maladeta (ES) mm w.e.
1976 1977 1978 1979 1980 1981 1982 1983 1984 1985
Careser (IT) mm w.e. -2710 -1720 -1640 -1820 -1810 -2650 -4330 -5120 -5710 -6470
Gries (CH) mm w.e. -3416 -2250 -1194 -2079 -1509 -1833 -3137 -3916 -3920 -4446
Hintereis (AT) mm w.e. -7221 -6461 -6050 -6269 -6319 -6492 -7732 -8312 -8280 -8854
Saint Sorlin (FR) mm w.e. -5960 -4630 -3770 -3540 -2630 -2430 -2890 -3030 -2650 -3120
Sarennes (FR) mm w.e. -18720 -17730 -17180 -17290 -16970 -16930 -17030 -17100 -17140 -18350
Vernagt (AT) mm w.e. 940 1292 1580 1624 1764 1709 864 327 347 235
Storglaciaeren (SE) mm w.e. -13920 -13720 -13800 -14010 -15280 -15470 -15210 -14930 -14810 -15530
Nigardsbreen (NO) mm w.e. 6410 5640 5510 6220 5000 5310 4890 5980 6320 6100
Austre Broeggerbreen (NO) mm w.e. -4870 -4980 -5540 -6250 -6770 -7320 -7360 -7630 -8360 -8910
Aalfotbreen (NO) mm w.e. 3660 3100 2590 2460 1850 2070 1940 3540 4860 4300
Hofsjokull N (IS) mm w.e.
Maladeta (ES) mm w.e.
1986 1987 1988 1989 1990 1991 1992 1993 1994 1995
Careser (IT) mm w.e. -7610 -9250 -10260 -11080 -12660 -14390 -15590 -15890 -17630 -18710
Gries (CH) mm w.e. -5393 -6126 -7050 -8121 -10109 -11453 -12578 -13630 -13839 -14117
Hintereis (AT) mm w.e. -9586 -10303 -11248 -11885 -12880 -14205 -15325 -15895 -17005 -17465
Saint Sorlin (FR) mm w.e. -4690 -5080 -4920 -7350 -8510 -9570 -11310 -12280 -12610 -11940
Sarennes (FR) mm w.e. -20140 -21060 -21750 -24340 -26480 -27840 -29150 -30350 -30980 -30220
Vernagt (AT) mm w.e. -573 -863 -1360 -1672 -2240 -3319 -4177 -4649 -5677 -6075
Storglaciaeren (SE) mm w.e. -15590 -15110 -15950 -14710 -14120 -13950 -13070 -12070 -12440 -11740
Nigardsbreen (NO) mm w.e. 6000 7480 6590 10060 11830 12030 13630 15480 16040 17230
Austre Broeggerbreen (NO) mm w.e. -9230 -9010 -9530 -9980 -10640 -10510 -10610 -11640 -11800 -12580
Aalfotbreen (NO) mm w.e. 3890 5960 3480 6410 8200 8990 11280 13460 14240 15440
Hofsjokull N (IS) mm w.e. 0 -740 -160 -760 -2170 -1110 -200 -120 -800
Maladeta (ES) mm w.e. 0 -327 -359 -8 -651
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
Careser (IT) mm w.e. -20030 -20960 -23200 -25000 -26610 -26860 -28009 -31326 -32888 -34893
Gries (CH) mm w.e. -14634 -15702 -17755 -18319 -19304 -19533 -20523 -23234 -24380 -25892
Hintereis (AT) mm w.e. -18292 -18883 -20115 -20976 -21609 -21782 -22429 -24243 -24910 -25971
Saint Sorlin (FR) mm w.e. -12450 -12610 -14830 -15870 -17110 -16950 -18640 -21590 -24040 -26540
Sarennes (FR) mm w.e. -30220 -30650 -32990 -34050 -35584 -35194 -37514 -40654 -43474 -46754
Vernagt (AT) mm w.e. -6488 -6975 -7978 -8086 -8373 -8597 -8863 -10996 -11403 -11926
Storglaciaeren (SE) mm w.e. -12130 -12760 -13280 -13460 -12880 -13580 -14410 -15450 -15570 -15640
Nigardsbreen (NO) mm w.e. 16820 17290 18260 18430 20150 19931 19043 17884 17841 18939
Austre Broeggerbreen (NO) mm w.e. -12750 -13460 -14320 -14680 -14700 -15180 -15760 -16660 -17780 -18780
Aalfotbreen (NO) mm w.e. 13560 13640 13750 13810 15800 13707 12177 9675 9575 10243
Hofsjokull N (IS) mm w.e. -1580 -2630 -3310 -3560 -4900 -5480 -6480 -7460 -8820 -9250
Maladeta (ES) mm w.e. -444 68 -887 -1651 -2551 -2049 -2860 -3962 -5478 -6957
2006 2007 2008
Careser (IT) mm w.e. -36986 -39731 -41683
Gries (CH) mm w.e. -27887 -29360
Hintereis (AT) mm w.e. -27487 -29284 -30519
Saint Sorlin (FR) mm w.e. -27980 -30230 -32040
Sarennes (FR) mm w.e. -49134 -51654 -53994
Vernagt (AT) mm w.e. -12808 -13774 -14617
Storglaciaeren (SE) mm w.e. -17360 -16950 -16370
Nigardsbreen (NO) mm w.e. 17540 18587 19677
Austre Broeggerbreen (NO) mm w.e. -19510 -19970 -20100
Aalfotbreen (NO) mm w.e. 7053 8323 9013
Hofsjokull N (IS) mm w.e. -9760 -10150 -10720
Maladeta (ES) mm w.e. -8744 -9691 -9728

Goals

Preparation of adjustment procedures to climatic conditions and mitigation of possible adverse effects.


Similar oscillations within the last 400 years are typical of all Alpine glaciers. Following the peak of the onset of the 17th century, glaciers remained at their maximum extents for the next 250 years, undergoing relatively insignificant changes. A majority of glaciers in the Eastern Alps reached their second peak between 1770 and 1780, and in the mid-19th century. However, the post-1920 period records a continuous retreat of glaciers; the only variations occurring between individual years and decades were those concerning the rate of glacier retreat. The shrinking of the Triglav glacier progressed during the 1990’s. The increasingly rapid thinning of the ice sheet caused individual rock formations to appear in the middle of the glacier, finally cutting it into two completely separate parts in 1992. The shrinking of the Triglav glacier is still continuing, with occasional halts in the process occurring in years with exceptionally high snow cover during late spring. The last time this occurred was in 2004, when, at the beginning of July, the snow measurement rod revealed more than 2 m of snow under the glacier. The snow cover remained in place until the end of melting season, so the glacier remained covered by snow and the measurements made no sense. The snow remained at the bottom of the glacier until the end of summer 2005, which is why the glacier’s surface in this year was greater than in 2003. The smallest glacier area was recorded in 2007, and measured 0.6 ha. At the end of the melting period in 2008, the glacier was still mainly covered with snow from the previous winter season, and its measured surface therefore amounted to 1.1 ha.

Similar trends are characteristic of all Alpine glaciers. The cause of rapidity in changes can be attributed to different elevations above sea level, position and glacier size.


Data for Slovenia

Objectives summarized by: Resolution on National Environmental Action Programme 2005-2012 (ReNPVO, Official Gazette of the RS, No. 2/06).
Source database or source: Anton Melik Geographical Institute at the Science and Research Centre of the Slovenian Academy of Sciences and Arts, the data was obtained by geodetical measurements and photogrammetric survey.
Data administrator: Anton Melik Geographical Institute at the Science and Research Centre of the Slovenian Academy of Sciences and Arts
Data acquisition date for this indicator: 10 September 2009
Methodology and frequency of data collection for the indicator: The data is presented for the 1992-2008 period.
Data processing methodology: Measurements are carried out every year at the end of the melting period – the end of August or September. Classical geodetic measurements are taken through theodolite and/or photogrammetric survey.
Information concerning data quality:
- Advantages and disadvantages of the indicator: The data is comparable with the database of the World Glacier Monitoring Service based in Zürich.
- Relevance, accuracy, robustness, uncertainty: In years when the glacier is covered by snow at the end of the melting period, it is not possible to measure the extent of ice, but only of snow, which is why the glacier's extent and volume are overrated in those years. Due to weather conditions, measurements cannot be performed each year on the same day at the end of the melting period, so the extent of the glacier is not lowest on the same day each year.
Reliability of the indicator (archive data): The data is not published in any publicly available databases, but in various scientific and expert articles.
Uncertainty of the indicator (scenarios/projections): No scenarios, projections available
-Overall estimate (1 = no major remarks, 3 = data with reservation):
Relevance: 1
Accuracy: 1
Completeness over time:1
Completeness over space: 1

Ever since 1946, the Anton Melik Geographical Institute at the Science and Research Centre of the Slovenian Academy of Sciences and Arts conducts regular annual measurements of the Triglav and Skuta glaciers.

In 1946, measuring points were set up around the Triglav glacier from which the distance to the glacier was measured with measuring tape. On the basis of these measures, glacier drawings were made by individual year as along with assessments of the glacier's surface area. With the glacier retreating, several measuring points became too remote, and subsequent years saw the establishment of new ones. Given that the locations of all measuring points are geodetically measured, it has been possible all these years to make fairly accurate calculations of the glacier's surface area. Along with performing measurements, the expert team of the Anton Melik Geographical Institute also took regular photographs of the glacier from Begunjski vrh. Moreover, these photographs serve as an excellent source for the reconstruction of the glacier's extent throughout the past decades. Since 1976, there has also been a regular monthly photographing of the glacier from two fixed locations on Kredarica. As a rule, regular annual measurements are performed in mid-September, at the end of the melting period. In some years, however, measurements were rendered impossible by early snowfall.

In 1952, 1995 and 1999, the glacier was also measured geodetically. Since 1999, an airborne photogrammetric survey has been organised every second year. This photographic material has facilitated the calculations of changes in the glacier’s surface area and volume between individual years. In 2005, an airborne photogrammetric survey was organised, whereas in 2007 and 2008 terrestrial photogrammetric surveys were carried out.

In 1999 and 2001, geo-radar measurements were carried out for the provision of data on ice layer thickness by individual cross-section.
To calculate a glacier’s volume, we need information on its surface and its rocky base. Data on surface by individual year was obtained on the basis of photogrammetric survey in individual years, while the data on the rocky base was obtained from geo-radar measurements that were carried out in 2001. However, the data on the glacier’s rocky base in particular may be problematic or not precise enough due to its karstic diversity. Data on glacier volume is therefore only an estimation.

The World Glacier Monitoring Service based in Zurich collects data on glacier oscillations. In several glaciers, the series of data dates as far back as 1894.


Related indicators