Amundsen Sea Embayment accumulation variability measured with GNSS-IR
In order to improve projections of the future ice-sheet surface mass balance and the interpretation of the isotopic signals of past accumulation preserved in ice cores, it is critical to understand the mechanisms that transport water vapor to the Antarctic continent. Global Navigation Satellite Syst...
Main Authors: | , , , , |
---|---|
Format: | Text |
Language: | English |
Published: |
2023
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-2023-114 https://tc.copernicus.org/preprints/tc-2023-114/ |
id |
ftcopernicus:oai:publications.copernicus.org:tcd113339 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:tcd113339 2023-09-05T13:11:45+02:00 Amundsen Sea Embayment accumulation variability measured with GNSS-IR Hoffman, Andrew O. Maclennan, Michelle Lenaerts, Jan Larson, Kristine M. Chrsitianson, Knut 2023-08-07 application/pdf https://doi.org/10.5194/tc-2023-114 https://tc.copernicus.org/preprints/tc-2023-114/ eng eng doi:10.5194/tc-2023-114 https://tc.copernicus.org/preprints/tc-2023-114/ eISSN: 1994-0424 Text 2023 ftcopernicus https://doi.org/10.5194/tc-2023-114 2023-08-14T16:24:22Z In order to improve projections of the future ice-sheet surface mass balance and the interpretation of the isotopic signals of past accumulation preserved in ice cores, it is critical to understand the mechanisms that transport water vapor to the Antarctic continent. Global Navigation Satellite System (GNSS) receivers distributed across Antarctica to monitor ice velocity and solid Earth motion can be used to understand accumulation, ablation, and snow redistribution at the ice-sheet surface. Here, we present a forward model for reflector height change between the GNSS antenna phase center and the snow surface and an inverse framework to determine accumulation rate and near-surface firn densification from the reflector height time series. We use this model to determine accumulation at the sites of three long-term on-ice GNSS receivers located in the Amundsen Sea Embayment (ASE) and at a network of GNSS receivers deployed in 2007–2008, 2008–2009, and 2009–2010 austral summers. From the GNSS-IR accumulation reconstructions, we find that extreme precipitation dominates total precipitation and that extreme event frequency varies seasonally. We use our GNSS-IR accumulation reconstructions together with reanalysis products to characterize the atmospheric conditions that promote extreme snowfall in the ASE. The blocking pressure systems that promote extreme accumulation on Thwaites Glacier are facilitated by tropical teleconnections, specifically convection that promotes Rossby waves trains from the Western Pacific, Indian, and Atlantic Oceans to the Amundsen and Bellingshausen Seas. Text Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Thwaites Glacier Copernicus Publications: E-Journals Antarctic The Antarctic Austral Amundsen Sea Pacific Indian Thwaites Glacier ENVELOPE(-106.750,-106.750,-75.500,-75.500) |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
In order to improve projections of the future ice-sheet surface mass balance and the interpretation of the isotopic signals of past accumulation preserved in ice cores, it is critical to understand the mechanisms that transport water vapor to the Antarctic continent. Global Navigation Satellite System (GNSS) receivers distributed across Antarctica to monitor ice velocity and solid Earth motion can be used to understand accumulation, ablation, and snow redistribution at the ice-sheet surface. Here, we present a forward model for reflector height change between the GNSS antenna phase center and the snow surface and an inverse framework to determine accumulation rate and near-surface firn densification from the reflector height time series. We use this model to determine accumulation at the sites of three long-term on-ice GNSS receivers located in the Amundsen Sea Embayment (ASE) and at a network of GNSS receivers deployed in 2007–2008, 2008–2009, and 2009–2010 austral summers. From the GNSS-IR accumulation reconstructions, we find that extreme precipitation dominates total precipitation and that extreme event frequency varies seasonally. We use our GNSS-IR accumulation reconstructions together with reanalysis products to characterize the atmospheric conditions that promote extreme snowfall in the ASE. The blocking pressure systems that promote extreme accumulation on Thwaites Glacier are facilitated by tropical teleconnections, specifically convection that promotes Rossby waves trains from the Western Pacific, Indian, and Atlantic Oceans to the Amundsen and Bellingshausen Seas. |
format |
Text |
author |
Hoffman, Andrew O. Maclennan, Michelle Lenaerts, Jan Larson, Kristine M. Chrsitianson, Knut |
spellingShingle |
Hoffman, Andrew O. Maclennan, Michelle Lenaerts, Jan Larson, Kristine M. Chrsitianson, Knut Amundsen Sea Embayment accumulation variability measured with GNSS-IR |
author_facet |
Hoffman, Andrew O. Maclennan, Michelle Lenaerts, Jan Larson, Kristine M. Chrsitianson, Knut |
author_sort |
Hoffman, Andrew O. |
title |
Amundsen Sea Embayment accumulation variability measured with GNSS-IR |
title_short |
Amundsen Sea Embayment accumulation variability measured with GNSS-IR |
title_full |
Amundsen Sea Embayment accumulation variability measured with GNSS-IR |
title_fullStr |
Amundsen Sea Embayment accumulation variability measured with GNSS-IR |
title_full_unstemmed |
Amundsen Sea Embayment accumulation variability measured with GNSS-IR |
title_sort |
amundsen sea embayment accumulation variability measured with gnss-ir |
publishDate |
2023 |
url |
https://doi.org/10.5194/tc-2023-114 https://tc.copernicus.org/preprints/tc-2023-114/ |
long_lat |
ENVELOPE(-106.750,-106.750,-75.500,-75.500) |
geographic |
Antarctic The Antarctic Austral Amundsen Sea Pacific Indian Thwaites Glacier |
geographic_facet |
Antarctic The Antarctic Austral Amundsen Sea Pacific Indian Thwaites Glacier |
genre |
Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Thwaites Glacier |
genre_facet |
Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Thwaites Glacier |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-2023-114 https://tc.copernicus.org/preprints/tc-2023-114/ |
op_doi |
https://doi.org/10.5194/tc-2023-114 |
_version_ |
1776196954034798592 |