Mass-Budget Anomalies and Geometry Signals of Three Austrian Glaciers

• Glacier mass-budget monitoring documents climate fluctuations, provides context for observed glacier-geometry changes, and can provide information on the glaciers' states. We examine the mass-budget series and available geometries of three well-documented glaciers located in the same catchment area less than 10 km from one another in the Austrian Otztal Alps. The altitudinal profiles of the 1981-2010 average specific mass budgets of each glacier serve as climatic reference. We apply these reference mass-budget profiles on all available glacier geometries, thereby retrieving for each glacier reference-climate mass budgets that reveal in a discrete way each glacier's geometric adjustment over time and its impact on mass loss; interpolation of the reference-climate mass budgets over the 1981-2010 period provides the glaciers' geometry signals. The geometric mass-budget anomalies derived with respect to these geometry signals indicate decreasing mass budgets over the 1981-2010 period by 0.020 m water equivalent (w.e.) a(-2), or 31% additional mass loss compared to the centered anomalies derived with respect to the 1981-2010 averages of the conventional mass-budget series. Reference-climate mass budgets with respect to 1981-2010 of older geometries highlight Hintereisferner's adapting geometry by almost continuous retreat since 1850. Further retreat is inevitable as Hintereisferner is the furthest from a steady state amongst the three glaciers. The relatively small Kesselwandferner has been also mostly retreating, while briefly advancing in response to short-term climatic trends. In a stable 1981-2010 climate, Kesselwandferner would relatively quickly reach a steady state. Vernagtferner's geometry since 1979 favors mass loss by thinning, primarily due to extended surge-related mass losses since 1845; this inability to retreat has led to - and will further - Vernagtferner's disintegration.

Subject headings

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Klimatforskning (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Climate Research (hsv//eng)

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Naturgeografi (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Physical Geography (hsv//eng)

Keyword

mass-budget anomalies

geometry change

geometry signal

climate forcing

glacier state

European Alps

Publication and Content Type

ref (subject category)

art (subject category)