Multibeam bathymetry and CTD measurements in two fjord systems in southeastern Greenland

Abstract

Abstract. We present bathymetry and hydrological observations collected in the summer of 2014 from two fjord systems in southeastern Greenland with a multibeam sonar system. Our results provide a detailed bathymetric map of the fjord complex around the island of Skjoldungen in Skjoldungen Fjord and the outer part of Timmiarmiut Fjord and show far greater depths compared to the International Bathymetric Chart of the Arctic Ocean. The hydrography collected shows different properties in the fjords with the bottom water masses below 240 m in Timmiarmiut Fjord being 1-2 • C warmer than in the two fjords around Skjoldungen, but data also illustrate the influence of sills on the exchange of deeper water masses within fjords. Moreover, evidence of subglacial discharge in Timmiarmiut Fjord, which is consistent with satellite observations of ice mélange set into motion, adds to our increasing understanding of the distribution of subglacial meltwater. Data are available through the PANGAEA website at https://doi.pangaea.de/10.1594/PANGAEA.860627.

BedMachine v3: Complete Bed Topography and Ocean Bathymetry Mapping of Greenland From Multibeam Echo Sounding Combined With Mass Conservation

“…In the region of Disko Bay, we relied on single‐beam and conductivity‐temperature‐depth data from Schumann et al (), and data from Holland et al () and Straneo et al () in Illulisat Icefjord. Bathymetry data were also available in the vicinity of Kangerdlussuaq (Sutherland et al, ), Nordvestfjord (Dowdeswell et al, ), Lille Gletscher (Chauché et al, ), Sermilik fjord (Straneo et al, ), Godthåbsfjord (Motyka et al, ), Sarqardleq fjord (Stevens et al, ), Timmiarmiut Fjord, Heimdal Glacier, and Skjoldungen Fjord (Kjeldsen et al, ); near the calving front of Bowdoin Glacier (Sugiyama et al, ); in Godthåbsfjord (S. Rysgaard, personal communication, 2017), in Young Sound fjord (Rysgaard et al, ); near Flade Isblink Ice Cap (Bendtsen et al, ); single‐beam data in northwest Greenland from the Ocean Research Project (ORP); and on the continental shelf along the southeast coast (Sutherland & Pickart, ). We also added vast amounts of single‐beam data from the Olex seabed mapping system (http://www.olex.no) as well as crowd‐sourced data from fishing and recreational vessels (MaxSea).…”

The Case for a Sustained Greenland Ice Sheet-Ocean Observing System (GrIOOS)

“…Frontal ablation at the ice-ocean interface, which includes submarine melting and iceberg calving, all influence ice sheet behavior and ice loss Kjeldsen et al, 2017). Submarine melting is largely thought to be controlled by the thermal forcing of the ocean waters reaching the glacier (Figure 2), and is amplified by large ocean velocities, such as those due to subglacial discharge driven turbulent, upwelling plumes at the glaciers' margins during the melt season (Mortensen et al, 2013;Bendtsen et al, 2015;Mankoff et al, 2016;Jackson et al, 2017).…”

“…Significant efforts have been made over the last decade to improve estimates of ice sheet bed elevation, particularly beneath the outlet glaciers of the GrIS, with airborne ice-penetrating radar (Leuschen et al, 2018). In addition, new bathymetric and airborne gravity surveys within multiple glacier fjords in Greenland have been made over the last few years as interest in ice sheet-ocean interactions has increased (e.g., Fenty et al, 2016;Rignot et al, 2016;Kjeldsen et al, 2017;Millan et al, 2018). These provide an even more detailed picture of the topography beneath glacier termini and within the fjord.…”

Grain Legumes and Fear of Salt Stress: Focus on Mechanisms and Management Strategies

“…To meet the challenge of feeding a continuous growing population and there will be an urgent need to enhance productivity around 87% or even more of what we are producing at present especially cereals and legumes by 2050 [1]. However, major abiotic constraints, which includes drought, heat, cold, and salinity critically threatens productivity and causes major yield loss in large areas [2,3,4]. Among these, salt stress (SS) is one of the major constraint to profitable crop production [5] and is likely to increase due to environmental changes and as a result of various irrigation malpractices.…”