Relationship of surface elevation changes of the Antarctic ice sheet with ice movement and subglacial water flow

Abstract

The article provides phenomenological and experimental arguments that ice sheet surface fluctuation in Antarctica is mediated by ice velocity and subglacial water flow. To understand this link we use temporal coherence to refer to the comparison between vertical profile and a shifted profile along the repeat ICESat track. A profile shift due to ice velocity is determined from cross-correlation between initial and shifted profiles. Ice velocity induced fluctuation in surface elevation and deformation of the vertical profile. The degree of coherence indicates a decrease in similarity of moving vertical profiles and their deformation. The water flow beneath the ice sheet and over the subglacial lakes generates irregular rise and fall of the surface. Observations in area of Dome A and its slope have revealed such behavior of surface, where the surface is placid and ice velocity is measly 2–5 m/y.

Keywords

• антарктида
• деформация
• когерентность
• подледниковые потоки воды
• скорость движения льда