Therefore, processes taking place at the termini of marine-terminating glaciers have a crucial importance and need considerable attention. Submarine melting and calving of tidewater glaciers represent a significant source of cold freshwater, hence also increasing the variability of temperature and salinity in the water column of glacial bays and fjords. Although the acceleration in their mass loss was 3 times smaller than that associated with the melting of Greenland and Antarctic ice sheets, the contribution of glaciers and ice caps to sea level rise is expected to remain substantial to the end of this century. According to recent research illustrating the scale of the phenomenon, glaciers and ice caps without peripheral ice bodies in Greenland and Antarctica lost mass at a rate of 120 ± 61 Gt yr −1 during 1961–1990, 278 ± 55 Gt yr −1 during 2001–2004, 215 ± 26 Gt yr −1 during 2003–2009 and 148 ± 30 Gt yr −1 during 2003–2010. Most glaciers around the world are losing mass and are contributing to global sea level rise. Similarly, the complete disintegration of the 15 km long ice tongue from Jakobshavn Isbræ, a marine-terminating outlet glacier in Greenland, in 2003 showed that such events are taking place in both hemispheres, in different environmental conditions. The spectacular detachment of 3200 km 2 of glacial ice from the Larsen B Ice Shelf in 2002 shed light on the importance of ice sheet stability and its relationship to climate shifts. We suggest that relatively inexpensive acoustic methods can be successfully used to provide quantitative descriptions of the various calving types. A quantitative analysis of the data reveals a robust correlation between ice impact energy and acoustic emission at frequencies below 200 Hz for subaerial calving. High-frequency underwater ambient noise recordings are combined with synchronized, high-resolution, time-lapse photography of the Hans Glacier cliff in Hornsund Fjord, Spitsbergen, to identify three types of calving events: typical subaerial, sliding subaerial, and submarine. Here we present the potential of hydroacoustic methods to investigate different modes of ice detachments. A detailed description of the mechanisms controlling the course of calving is essential for the reliable estimation and prediction of mass loss from glaciers. Tidewater glaciers lose volume through the poorly understood process of calving. Furthermore, the natural frequency and low frequency vibrations were discussed based on the interference between the detached bubbles and the air column vibrations.Climate-driven ice-water interactions in the contact zone between marine-terminating glaciers and the ocean surface show a dynamic and complex nature. In the analysis, the deformation behavior, the oscillation frequencies, sound pressure, and radius variation were discussed by comparing the numerical and experimental data. To analyze the bubble deformation process, a computational fluid dynamics (CFD) simulation was conducted using the volume of fluid (VOF) method to predict the sound emission.
In this study, the deformation of a bubble was observed, and the sound emitted upon detachment was measured experimentally. The bubble deformation and sound emission generated after detachment has been investigated in many studies, in which the breathing mode with a natural frequency was discussed based on the dynamics of the interface between the air and water.
Abstract : When a bubble detaches from a nozzle immersed in water, a sound is emitted owing to the detachment.
0 kommentar(er)
