ETOPO1 Global Relief Model converted to PanMap layer format

ETOPO1 is a 1 arc-minute global relief model of Earth's surface that integrates land topography and ocean bathymetry. It was built from numerous global and regional data sets. Data were converted to the PanMap layer format in 14 contour lines from 500 to 7000 meter in steps of 500 m. The link provides a zip-archive (1.1 MB) with *.lay files. The PanMap Mini-GIS software is published at doi:10.1594/PANGAEA.104840.

Near-bottom zooplankton aggregations in Kongsfjorden with link to images from the optical zooplankton sensor MOKI

Near-bottom zooplankton communities have rarely been studied despite numerous reports of high zooplankton concentrations, probably due to methodological constraints. In Kongsfjorden, Svalbard, the near-bottom layer was studied for the first time by combining daytime deployments of a remotely operated vehicle (ROV), the optical zooplankton sensor moored on-sight key species investigation (MOKI), and Tucker trawl sampling. ROV data from the fjord entrance and the inner fjord showed high near-bottom abundances of euphausiids with a mean concentration of 17.3 ± 3.5 n/100 m**3. With the MOKI system, we observed varying numbers of euphausiids, amphipods, chaetognaths, and copepods on the seafloor at six stations. Light-induced zooplankton swarms reached densities in the order of 90,000 (euphausiids), 120,000 (amphipods), and 470,000 ind/m**3 (chaetognaths), whereas older copepodids of Calanus hyperboreus and C. glacialis did not respond to light. They were abundant at the seafloor and 5 m above and showed maximum abundance of 65,000 ind/m**3. Tucker trawl data provided an overview of the seasonal vertical distribution of euphausiids. The most abundant species Thysanoessa inermis reached near-bottom concentrations of 270 ind/m**3. Regional distribution was neither related to depth nor to location in the fjord. The taxa observed were all part of the pelagic community. Our observations suggest the presence of near-bottom macrozooplankton also in other regions and challenge the current view of bentho-pelagic coupling. Neglecting this community may cause severe underestimates of the stock of elagic zooplankton, especially predatory species, which link secondary production with higher trophic levels.

Orthophotokarte Vernagtferner 1979 in jpg-Format (54 MB)

For the production of the orthophoto map Vernagtferner 1979, scale I: 10000, photographs of the flight "Hintereisferner 1979" were used, which have been found to be very suitable for differential rectification. Control points were determined before the flight took place. The processing of nine stereopairs was carried out on an analytical plotter. Simultaneously with the on-line plotting of the contour lines the reference data for the computation of the profiles for the differential rectification were recorded. The orthophoto map was covered by four aerial photographs. A smooth data transfer was ensured because the same computer was used for the data acquisition and the differential rectification. Two printing originals were prepared, one for the outline drawings with contour lines and another for the orthophoto. The print was done in black for the two copies. The data acquisition, the computation of the scanning profiles for the othoprojector and the procedure of the differential rectification are described. The reason for the use of on-line drawn contour lines is explained. Further applications, also for digital contour lines, are introduced. Possibilities for the achievement of high photo quality during the reproduction are discussed.