The NOAA IR serves as an archival repository of NOAA-published products including scientific findings, journal articles, guidelines, recommendations, or other information authored or co-authored by NOAA or funded partners.
As a repository, the NOAA IR retains documents in their original published format to ensure public access to scientific information.
i
Firn cold content evolution at nine sites on the Greenland ice sheet between 1998 and 2017
-
2020
-
-
Source: Journal of Glaciology, 66(258), 591-602
[PDF-1.17 MB]
Details:
-
Journal Title:Journal of Glaciology
-
Personal Author:
-
NOAA Program & Office:
-
Description:Current sea-level rise partly stems from increased surface melting and meltwater runoff from the Greenland ice sheet. Multi-year snow, also known as firn, covers about 80% of the ice sheet and retains part of the surface meltwater. Since the firn cold content integrates its physical and thermal characteristics, it is a valuable tool for determining the meltwater-retention potential of firn. We use gap-filled climatological data from nine automatic weather stations in the ice-sheet accumulation area to drive a surface-energy-budget and firn model, validated against firn density and temperature observations, over the 1998–2017 period. Our results show a stable top 20 m firn cold content (CC20) at most sites. Only at the lower-elevation Dye-2 site did CC20 decrease, by 24% in 2012, before recovering to its original value by 2017. Heat conduction towards the surface is the main process feeding CC20 at all nine sites, while CC20 reduction occurs through low-cold-content fresh-snow addition at the surface during snowfall and latent-heat release when meltwater refreezes. Our simulations suggest that firn densification, while reducing pore space for meltwater retention, increases the firn cold content, enhances near-surface meltwater refreezing and potentially sets favourable conditions for ice-slab formation.
-
Keywords:
-
Source:Journal of Glaciology, 66(258), 591-602
-
DOI:
-
Document Type:
-
Place as Subject:
-
Rights Information:CC BY-NC-ND
-
Compliance:Submitted
-
Main Document Checksum:
-
Download URL:
-
File Type:
