528 resultados para 1969

em Publishing Network for Geoscientific


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Vernagtferner in the Ötztaler Alps (Tirol) has been mapped after terrestrial-photogrammetric surveying by Sebastian Finsterwalder in 1889, Otto von Gruber in 1912, and Heinrich Schatz in 1938. The new, four-colored map in the scale 1: 10.000 enclosed in this issue was composed from aerial photographs of 1969. It was conceived as topographicaI map with additional geodetic and glaciological content. The methods of survey are explained and the means of cartographic representation are discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Glacier inventories provide the basis for further studies on mass balance and volume change, relevant for local hydrological issues as well as for global calculation of sea level rise. In this study, a new Austrian glacier inventory has been compiled, updating data from 1969 (GI 1) and 1998 (GI 2) based on high-resolution lidar digital elevation models (DEMs) and orthophotos dating from 2004 to 2012 (GI 3). To expand the time series of digital glacier inventories in the past, the glacier outlines of the Little Ice Age maximum state (LIA) have been digitalized based on the lidar DEM and orthophotos. The resulting glacier area for GI 3 of 415.11 ± 11.18 km**2 is 44% of the LIA area. The annual relative area losses are 0.3%/yr for the ~119-year period GI LIA to GI 1 with one period with major glacier advances in the 1920s. From GI 1 to GI 2 (29 years, one advance period of variable length in the 1980s) glacier area decreased by 0.6% yr?1 and from GI 2 to GI 3 (10 years, no advance period) by 1.2%/yr. Regional variability of the annual relative area loss is highest in the latest period, ranging from 0.3 to 6.19%/yr. The mean glacier size decreased from 0.69 km**2 (GI 1) to 0.46 km**2 (GI 3), with 47% of the glaciers being smaller than 0.1 km**2 in GI 3 (22%).