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  • Direct Measurement of Glacier Ice Melt: Boundary Layer Details Are Critical for Submarine Melt Prediction at Near‐Vertical Ice Faces
Title: Direct Measurement of Glacier Ice Melt: Boundary Layer Details Are Critical for Submarine Melt Prediction at Near‐Vertical Ice Faces
Abstract Parameterization of submarine melting represents a large source of uncertainty in modeling ice sheet response to climate change. Here we present in situ observations of melt at near‐vertical ice faces using a novel instrument platform mounted rigidly to icebergs. We investigate boundary layer dynamics controlling melt across 31 measurement periods that span a range of momentum and thermal forcing (1–12 cm/s flows and 3–10 K). While melt generally scales with velocity and temperature, we find substantially enhanced melt linked with unsteady forcing. Several implementations of the three‐equation melt parameterization show melt can be predicted within a factor of 2 if the model is evaluated with peak near‐boundary velocities and flows are quasi‐steady. However, if flows are unsteady or the model is evaluated with low‐resolution velocities, melt is underpredicted by 2– We conclude that understanding the detailed character of near‐boundary flows is critical for submarine melt predictions.  more » « less
Award ID(s):
2319494 2138790 2528827 2023674
PAR ID:
10608233
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
52
Issue:
11
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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