Triglavski ledenik

The Triglav Glacier lies on the southeast edge of the Alps, in the Julian Alps below Mount Triglav, Slovenia’s highest peak. Its upper edge lies at 2,500 m. The glacier has been regularly measured, observed, and studied since 1946 by the Anton Melik Geographical Institute at ZRC SAZU. When measurements began it covered 14.4 ha, but today it covers less than half a hectare. The glacier no longer has all glacial features. Thus one may only speak of a glacier because of its past, when it clearly had the basic features of an alpine glacier. Analysis of the geomorphic forms of the Triglav Mountains allows reconstruction of past glaciation. Moraine deposits above the upper edge of Mount Triglav’s North Wall indicate the glacier’s extent during the Little Ice Age. When this ended in the nineteenth century, visits to the Triglav Mountains started increasing, and so there are many written and pictorial sources available from this time. The measurement period can be divided into four parts regarding glacial fluctuation. From 1946 to 1964 there was pronounced glacial retreat. The first geodetic measurement was in 1952. Based on these measurements, one can calculate the volume of the glacier. The second period, 1965 to 1982, saw stagnation in the glacier’s retreat. In most years the glacier was also covered with snow at the end of the melting period. The third period, 1983 to 2003, saw the fastest retreat of the glacier. Measurements were updated in the 1990s. In 1999 regular photogrammetric measurements began. That year we measured the thickness of the ice with ground-penetrating radar for the first time. In the last period after 2003, the glacier’s shrinkage has again slowed.

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Triglavski ledenik od leta 1946 redno merijo, opazujejo in preučujejo sodelavci Geografskega inštituta Antona Melika ZRC SAZU. Na začetku meritev je bila njegova površina 14,4 ha, do danes pa se je skrčil na slabo polovico hektarja. Zdaj ledenik nima več vseh ledeniških značilnosti. O ledeniku lahko govorimo le še zaradi njegove preteklosti, na osnovi analize geomorfnih oblik Triglavskega pogorja ter pisnih in slikovnih virov iz 19.in 20. stoletja. Obdobje meritev z vidika kolebanja ledenika kronološko delimo na štiri dele. Prva leta do leta 1964 je zaznamovalo krčenje ledenika. Leta 1952 je bil ledenik prvič geodetsko izmerjen. Na podlagi teh meritev smo lahko izračunali tudi prostornino ledenika. Drugo obdobje od leta 1965 do leta 1982 je zaznamovala stagnacija v krčenju ledenika. V večini let je ledenik tudi ob koncu talilne dobe prekrival sneg. Tretje razdobje med letoma 1983 in 2003 je zaznamoval najhitrejši umik ledenika. V devetdesetih letih 20. stoletja smo posodobili meritve, leta 1999 smo začeli z rednimi fotogrametričnimi meritvami, tega leta smo prvič izmerili debelino ledu z georadarjem. V zadnjem razdobju po letu 2003 se je krčenje ledenika znova upočasnilo.