Glacier recession in Iceland and Austria

Abstract

Valley and mountain glaciers and ice caps respond to changes in regional climate on the scale of decades; thus, they can serve as indicators of regional climate change. During the last century, most valley and mountain glaciers and ice caps receded [Meier, 1984; Haeberli et al., 1989], although some advances have occurred during periods of cooling [Wood, 1988]. Glaciers in Iceland [Rist, 1975] and in the eastern Alps of Austria [Patzelt, 1980] have followed a similar pattern. Images acquired by satellite sensors can provide a regional overview for studying changes in glacier area, terminus position, glacier facies [Williams et al., 1991], and the position of the regional snow line, while insitu studies usually provide measurements at only a single point. Major changes in glaciers may be obvious from initial inspection of satellite images; however, detailed study of digital image data can reveal the presence of small changes that are useful indicators of regional trends in glacier mass balance. If observed over a long enough period of time in many different geographic settings, glacier‐terminus position changes can be related to changes in regional and even global climate.

Glacial cover mapping (1987–1996) of the Cordillera Blanca (Peru) using satellite imagery

“…For satellite imagery, this accuracy is limited by the sensor resolution: 79 m for Landsat MSS and 30 m for Landsat TM (Hall et al, 1992(Hall et al, , 1995aWilliams et al, 1997). According to Hall et al (2003), for multi-temporal measures of the glacier front position using satellite images, each position has an uncertainty that can be calculated by the following formula:…”

“…Globally, mountain glaciers generally have been retreating since the later part of the 19th century (end of the bLittle Ice AgeQ; Hall et al, 1995a). 0034 Multitemporal satellite image analysis is an important tool for monitoring land cover (LULCC, 2003), as well as variations in the total area of glaciers, the position of their front and their general facies (Hall, 2002;Hall et al, 1987Hall et al, , 1988Hall et al, , 1992Hall et al, , 1995aWilliams et al, 1991). Satellite imagery serves both as an excellent base map for regional studies of alpine glaciation and as a means of placing local field studies within their regional context (Klein & Isacks, 1998).…”

Combining satellite multispectral image data and a digital elevation model for mapping debris-covered glaciers

“…However, many valley glaciers are covered to a varying extent by supraglacial debris, which has the same spectral characteristics as the surrounding terrain and, thus, cannot be spectrally discerned from it. As a consequence, previous studies related to quantitative assessments of glacier change (area/length) applied manual delineation of debris-covered glaciers, mostly by on-screen digitizing (e.g., Bayr et al, 1994;Hall et al, 1992;Jacobs et al, 1997;Paul, 2002a,b;Williams et al, 1997). Although manual delineation of debris-covered glacier ice generally produces accurate results, it is very time-consuming and labour intensive for studying a larger number of glaciers.…”

Glacier extent and volume change (1966∼2000) on the Su-lo Mountain in northeastern Tibetan Plateau, China

“…The measurement accuracy of the glacier front position depends on the spatial resolution of the dataset and errors in imagery registration (Hall et al 1992& 1995, Williams et al 1997, Silverio et al 2005, Ye et al 2006b). The terminus change uncertainty U is estimated from (Hall et al 2003, Silverio et al 2005…”