Modeling winter precipitation over the Juneau Icefield, Alaska, using a linear model of orographic precipitation
Assessing and modeling precipitation in mountainous areas remains a major challenge in glacier mass balance modeling. Observations are typically scarce and reanalysis data and similar climate products are too coarse to accurately capture orographic effects. Here we use the linear theory of orographi...
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ftoslouniv:oai:www.duo.uio.no:10852/71220 2023-05-15T16:20:40+02:00 Modeling winter precipitation over the Juneau Icefield, Alaska, using a linear model of orographic precipitation Roth, Aurora Hock, Regine Schuler, Thomas Bieniek, Peter A. Pelto, Mauri Aschwanden, Andy 2018-07-23T13:57:14Z http://hdl.handle.net/10852/71220 http://urn.nb.no/URN:NBN:no-74357 https://doi.org/10.3389/feart.2018.00020 EN eng Frontiers Media http://urn.nb.no/URN:NBN:no-74357 Roth, Aurora Hock, Regine Schuler, Thomas Bieniek, Peter A. Pelto, Mauri Aschwanden, Andy . Modeling winter precipitation over the Juneau Icefield, Alaska, using a linear model of orographic precipitation. Frontiers in Earth Science. 2018, 6:20, 1-19 http://hdl.handle.net/10852/71220 1598371 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Frontiers in Earth Science&rft.volume=6:20&rft.spage=1&rft.date=2018 Frontiers in Earth Science 6 https://doi.org/10.3389/feart.2018.00020 URN:NBN:no-74357 Fulltext https://www.duo.uio.no/bitstream/handle/10852/71220/1/feart-06-00020.pdf Attribution 4.0 International https://creativecommons.org/licenses/by/4.0/ CC-BY 2296-6463 Journal article Tidsskriftartikkel Peer reviewed PublishedVersion 2018 ftoslouniv https://doi.org/10.3389/feart.2018.00020 2020-06-21T08:52:52Z Assessing and modeling precipitation in mountainous areas remains a major challenge in glacier mass balance modeling. Observations are typically scarce and reanalysis data and similar climate products are too coarse to accurately capture orographic effects. Here we use the linear theory of orographic precipitation model (LT model) to downscale winter precipitation from the Weather Research and Forecasting Model (WRF) over the Juneau Icefield, one of the largest ice masses in North America (>4,000 km2), for the period 1979–2013. The LT model is physically-based yet computationally efficient, combining airflow dynamics and simple cloud microphysics. The resulting 1 km resolution precipitation fields show substantially reduced precipitation on the northeastern portion of the icefield compared to the southwestern side, a pattern that is not well captured in the coarse resolution (20 km) WRF data. Net snow accumulation derived from the LT model precipitation agrees well with point observations across the icefield. To investigate the robustness of the LT model results, we perform a series of sensitivity experiments varying hydrometeor fall speeds, the horizontal resolution of the underlying grid, and the source of the meteorological forcing data. The resulting normalized spatial precipitation pattern is similar for all sensitivity experiments, but local precipitation amounts vary strongly, with greatest sensitivity to variations in snow fall speed. Results indicate that the LT model has great potential to provide improved spatial patterns of winter precipitation for glacier mass balance modeling purposes in complex terrain, but ground observations are necessary to constrain model parameters to match total amounts. Article in Journal/Newspaper glacier Alaska Universitet i Oslo: Digitale utgivelser ved UiO (DUO) Juneau Icefield ENVELOPE(-134.254,-134.254,58.916,58.916) Frontiers in Earth Science 6 |
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Open Polar |
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Universitet i Oslo: Digitale utgivelser ved UiO (DUO) |
op_collection_id |
ftoslouniv |
language |
English |
description |
Assessing and modeling precipitation in mountainous areas remains a major challenge in glacier mass balance modeling. Observations are typically scarce and reanalysis data and similar climate products are too coarse to accurately capture orographic effects. Here we use the linear theory of orographic precipitation model (LT model) to downscale winter precipitation from the Weather Research and Forecasting Model (WRF) over the Juneau Icefield, one of the largest ice masses in North America (>4,000 km2), for the period 1979–2013. The LT model is physically-based yet computationally efficient, combining airflow dynamics and simple cloud microphysics. The resulting 1 km resolution precipitation fields show substantially reduced precipitation on the northeastern portion of the icefield compared to the southwestern side, a pattern that is not well captured in the coarse resolution (20 km) WRF data. Net snow accumulation derived from the LT model precipitation agrees well with point observations across the icefield. To investigate the robustness of the LT model results, we perform a series of sensitivity experiments varying hydrometeor fall speeds, the horizontal resolution of the underlying grid, and the source of the meteorological forcing data. The resulting normalized spatial precipitation pattern is similar for all sensitivity experiments, but local precipitation amounts vary strongly, with greatest sensitivity to variations in snow fall speed. Results indicate that the LT model has great potential to provide improved spatial patterns of winter precipitation for glacier mass balance modeling purposes in complex terrain, but ground observations are necessary to constrain model parameters to match total amounts. |
format |
Article in Journal/Newspaper |
author |
Roth, Aurora Hock, Regine Schuler, Thomas Bieniek, Peter A. Pelto, Mauri Aschwanden, Andy |
spellingShingle |
Roth, Aurora Hock, Regine Schuler, Thomas Bieniek, Peter A. Pelto, Mauri Aschwanden, Andy Modeling winter precipitation over the Juneau Icefield, Alaska, using a linear model of orographic precipitation |
author_facet |
Roth, Aurora Hock, Regine Schuler, Thomas Bieniek, Peter A. Pelto, Mauri Aschwanden, Andy |
author_sort |
Roth, Aurora |
title |
Modeling winter precipitation over the Juneau Icefield, Alaska, using a linear model of orographic precipitation |
title_short |
Modeling winter precipitation over the Juneau Icefield, Alaska, using a linear model of orographic precipitation |
title_full |
Modeling winter precipitation over the Juneau Icefield, Alaska, using a linear model of orographic precipitation |
title_fullStr |
Modeling winter precipitation over the Juneau Icefield, Alaska, using a linear model of orographic precipitation |
title_full_unstemmed |
Modeling winter precipitation over the Juneau Icefield, Alaska, using a linear model of orographic precipitation |
title_sort |
modeling winter precipitation over the juneau icefield, alaska, using a linear model of orographic precipitation |
publisher |
Frontiers Media |
publishDate |
2018 |
url |
http://hdl.handle.net/10852/71220 http://urn.nb.no/URN:NBN:no-74357 https://doi.org/10.3389/feart.2018.00020 |
long_lat |
ENVELOPE(-134.254,-134.254,58.916,58.916) |
geographic |
Juneau Icefield |
geographic_facet |
Juneau Icefield |
genre |
glacier Alaska |
genre_facet |
glacier Alaska |
op_source |
2296-6463 |
op_relation |
http://urn.nb.no/URN:NBN:no-74357 Roth, Aurora Hock, Regine Schuler, Thomas Bieniek, Peter A. Pelto, Mauri Aschwanden, Andy . Modeling winter precipitation over the Juneau Icefield, Alaska, using a linear model of orographic precipitation. Frontiers in Earth Science. 2018, 6:20, 1-19 http://hdl.handle.net/10852/71220 1598371 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Frontiers in Earth Science&rft.volume=6:20&rft.spage=1&rft.date=2018 Frontiers in Earth Science 6 https://doi.org/10.3389/feart.2018.00020 URN:NBN:no-74357 Fulltext https://www.duo.uio.no/bitstream/handle/10852/71220/1/feart-06-00020.pdf |
op_rights |
Attribution 4.0 International https://creativecommons.org/licenses/by/4.0/ |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.3389/feart.2018.00020 |
container_title |
Frontiers in Earth Science |
container_volume |
6 |
_version_ |
1766008629912141824 |