Wintertime storage of water in buried supraglacial lakes across the Greenland Ice Sheet

Abstract

Abstract. Surface melt over the Greenland Ice Sheet (GrIS) is increasing and estimated to account for half or more of the total mass loss. Little, however, is known about the hydrologic pathways that route surface melt within the ice sheet. In this study, we present over-winter storage of water in buried supraglacial lakes as one hydrologic pathway for surface melt, referred to as buried lakes. Airborne radar echograms are used to detect the buried lakes that are distributed extensively around the margin of the GrIS. The subsurface water can persist through multiple winters and is, on average, ~4.2 + 0.4 m below the surface. The few buried lakes that are visible at the surface of the GrIS have a~unique visible signature associated with a darker blue color where subsurface water is located. The volume of retained water in the buried lakes is likely insignificant compared to the total mass loss from the GrIS but the water will have important implications locally for the development of the englacial hydrologic network, ice temperature profiles and glacial dynamics. The buried lakes represent a small but year-round source of meltwater in the GrIS hydrologic system.

Meltwater produced by wind–albedo interaction stored in an East Antarctic ice shelf

“…The meltwater lakes were delineated manually, using a combination of visible Landsat imagery and high-resolution (∼6.25 m) geo-referenced amplitude images from the L-band Synthetic Aperture Radar sensor (PALSAR) onboard ALOS satellite (level 1.5 of the Fine Beam Single polarization mode). L-band radar is ideally suited for detection of surface and buried meltwater lakes 34 . The radar images we selected date back from the 2010-2011 summer season, an average melt season ( Supplementary Fig.…”

The Generation of Mega Glacial Meltwater Floods and Their Geologic Impact

“…This was followed one Hale solar cycle later (11,549 cal yrs BP) by an almost equally large acidity spike, which coincided with an abrupt climatic cooling followed by a decade-long warming that ended the YD and heralded the beginning of the Holocene. This terminal event also appears to coincide with a small 10 Be deposition rate peak. Also, Mörner [44] has observed that around 11,550 years BP, the Earth's magnetic field intensity increased by more than fivefold.…”

“…This event occurred immediately after a dramatic rise in atmospheric 14 C concentration that dates around 12,837 years BP in the Cariaco Basin radiocarbon record. It was associated with spikes in 10 Be concentration, nitrate ion concentration, and ice acidity as seen in the GISP 2 Greenland ice core record. All of these suggest that the Earth at that time had been impacted by a super solar proton event (SPE) [43].…”

“…H5 is found to follow: a) the Laschamp geomagnetic intensity minimum and geomagnetic reversal which extended from 40.8-42.3 k cal yrs BP [81], b) a very dramatic rise in 14 C excess from 42-40 k cal yrs BP [79], and c) a very large 10 Be spike centred at 41 k cal yrs BP [82], all indicating a period of extremely high solar and galactic cosmic ray activity. Also, Heinrich event H3 is found to correlate with the Mono Lake geomagnetic minimum and geomagnetic excursion which extended from 35-32 k cal yrs BP [83].…”

“…However, Koenig et al [10] report that some lakes survive through the winter season as buried lakes located on average about 2 meters below the surface. They found that these could re-emerge as supraglacial lakes during the following melt season or in other cases can remain buried for multiple seasons before re-emerging.…”