Arctic sea ice sensitivity to lateral melting representation in a coupled climate model
The melting of sea ice floes from the edges (lateral melting) results in open water formation and subsequently increases absorption of solar shortwave energy. However, lateral melt plays a small role in the sea ice mass budget in both hemispheres in most climate models (Keen et al., 2020). This is l...
Main Authors: | , , |
---|---|
Format: | Text |
Language: | English |
Published: |
2021
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-2021-67 https://tc.copernicus.org/preprints/tc-2021-67/ |
id |
ftcopernicus:oai:publications.copernicus.org:tcd93115 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:tcd93115 2023-05-15T13:11:55+02:00 Arctic sea ice sensitivity to lateral melting representation in a coupled climate model Smith, Madison Holland, Marika Light, Bonnie 2021-03-05 application/pdf https://doi.org/10.5194/tc-2021-67 https://tc.copernicus.org/preprints/tc-2021-67/ eng eng doi:10.5194/tc-2021-67 https://tc.copernicus.org/preprints/tc-2021-67/ eISSN: 1994-0424 Text 2021 ftcopernicus https://doi.org/10.5194/tc-2021-67 2021-03-08T17:22:13Z The melting of sea ice floes from the edges (lateral melting) results in open water formation and subsequently increases absorption of solar shortwave energy. However, lateral melt plays a small role in the sea ice mass budget in both hemispheres in most climate models (Keen et al., 2020). This is likely influenced by simple parameterizations of this process in sea ice models that are constrained by limited observations. Here we use a coupled climate model (CESM2.0) to assess the sensitivity of modeled sea ice state to the lateral melt parameterization. The results show that sea ice is sensitive both to the parameters determining the effective lateral melt rate, as well as the nuances in how lateral melting is applied to the ice pack. Increasing the lateral melt rate within the range of reasonable values is largely compensated by decreases in the basal melt rate, but can still result in a significant decrease in sea ice concentration and thickness, particularly in the marginal ice zone. We suggest that it is important to consider the efficiency of melt processes at forming open water, which drives the majority of the ice-albedo feedback. Melt processes are more efficient at forming open water in thinner ice scenarios (as we are likely to see in the future), suggesting the importance of well representing thermodynamic evolution. Revisiting model parameterizations of lateral melting with observations will require finding new ways to represent important physical processes. Text albedo Arctic ice pack Sea ice Copernicus Publications: E-Journals Arctic |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
The melting of sea ice floes from the edges (lateral melting) results in open water formation and subsequently increases absorption of solar shortwave energy. However, lateral melt plays a small role in the sea ice mass budget in both hemispheres in most climate models (Keen et al., 2020). This is likely influenced by simple parameterizations of this process in sea ice models that are constrained by limited observations. Here we use a coupled climate model (CESM2.0) to assess the sensitivity of modeled sea ice state to the lateral melt parameterization. The results show that sea ice is sensitive both to the parameters determining the effective lateral melt rate, as well as the nuances in how lateral melting is applied to the ice pack. Increasing the lateral melt rate within the range of reasonable values is largely compensated by decreases in the basal melt rate, but can still result in a significant decrease in sea ice concentration and thickness, particularly in the marginal ice zone. We suggest that it is important to consider the efficiency of melt processes at forming open water, which drives the majority of the ice-albedo feedback. Melt processes are more efficient at forming open water in thinner ice scenarios (as we are likely to see in the future), suggesting the importance of well representing thermodynamic evolution. Revisiting model parameterizations of lateral melting with observations will require finding new ways to represent important physical processes. |
format |
Text |
author |
Smith, Madison Holland, Marika Light, Bonnie |
spellingShingle |
Smith, Madison Holland, Marika Light, Bonnie Arctic sea ice sensitivity to lateral melting representation in a coupled climate model |
author_facet |
Smith, Madison Holland, Marika Light, Bonnie |
author_sort |
Smith, Madison |
title |
Arctic sea ice sensitivity to lateral melting representation in a coupled climate model |
title_short |
Arctic sea ice sensitivity to lateral melting representation in a coupled climate model |
title_full |
Arctic sea ice sensitivity to lateral melting representation in a coupled climate model |
title_fullStr |
Arctic sea ice sensitivity to lateral melting representation in a coupled climate model |
title_full_unstemmed |
Arctic sea ice sensitivity to lateral melting representation in a coupled climate model |
title_sort |
arctic sea ice sensitivity to lateral melting representation in a coupled climate model |
publishDate |
2021 |
url |
https://doi.org/10.5194/tc-2021-67 https://tc.copernicus.org/preprints/tc-2021-67/ |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
albedo Arctic ice pack Sea ice |
genre_facet |
albedo Arctic ice pack Sea ice |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-2021-67 https://tc.copernicus.org/preprints/tc-2021-67/ |
op_doi |
https://doi.org/10.5194/tc-2021-67 |
_version_ |
1766249521797398528 |