Validation of the sea ice surface albedo scheme of the regional climate model HIRHAM–NAOSIM using aircraft measurements during the ACLOUD/PASCAL campaigns
For large-scale and long-term Arctic climate simulations appropriate parameterization of the surface albedo is required. Therefore, the sea ice surface (SIS) albedo parameterization of the coupled regional climate model HIRHAM–NAOSIM was examined against broadband surface albedo measurements perform...
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ftcopernicus:oai:publications.copernicus.org:tc73244 2023-05-15T13:10:31+02:00 Validation of the sea ice surface albedo scheme of the regional climate model HIRHAM–NAOSIM using aircraft measurements during the ACLOUD/PASCAL campaigns Jäkel, Evelyn Stapf, Johannes Wendisch, Manfred Nicolaus, Marcel Dorn, Wolfgang Rinke, Annette 2019-06-26 application/pdf https://doi.org/10.5194/tc-13-1695-2019 https://tc.copernicus.org/articles/13/1695/2019/ eng eng doi:10.5194/tc-13-1695-2019 https://tc.copernicus.org/articles/13/1695/2019/ eISSN: 1994-0424 Text 2019 ftcopernicus https://doi.org/10.5194/tc-13-1695-2019 2020-07-20T16:22:47Z For large-scale and long-term Arctic climate simulations appropriate parameterization of the surface albedo is required. Therefore, the sea ice surface (SIS) albedo parameterization of the coupled regional climate model HIRHAM–NAOSIM was examined against broadband surface albedo measurements performed during the joint ACLOUD (Arctic CLoud Observations Using airborne measurements during polar Day) and PASCAL (Physical feedbacks of Arctic boundary layer, Sea ice, Cloud and AerosoL) campaigns, which were performed in May–June 2017 north of Svalbard. The SIS albedo parameterization was tested using measured quantities of the prognostic variables surface temperature and snow depth to calculate the surface albedo and the individual fractions of the ice surface subtypes (snow-covered ice, bare ice, and melt ponds) derived from digital camera images taken on board the Polar 5 and 6 aircraft. The selected low-altitude (less than 100 m) flight sections of overall 12 flights were performed over surfaces dominated by snow-covered ice. It was found that the range of parameterized SIS albedo for individual days is smaller than that of the measurements. This was attributed to the biased functional dependence of the SIS albedo parameterization on temperature. Furthermore, a time-variable bias was observed with higher values compared to the modeled SIS albedo (0.88 compared to 0.84 for 29 May 2017) in the beginning of the campaign, and an opposite trend towards the end of the campaign (0.67 versus 0.83 for 25 June 2017). Furthermore, the surface type fraction parameterization was tested against the camera image product, which revealed an agreement within 1 %. An adjustment of the variables, defining the parameterized SIS albedo, and additionally accounting for the cloud cover could reduce the root-mean-squared error from 0.14 to 0.04 for cloud free/broken cloud situations and from 0.06 to 0.05 for overcast conditions. Text albedo Arctic Sea ice Svalbard Copernicus Publications: E-Journals Arctic Svalbard The Cryosphere 13 6 1695 1708 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
For large-scale and long-term Arctic climate simulations appropriate parameterization of the surface albedo is required. Therefore, the sea ice surface (SIS) albedo parameterization of the coupled regional climate model HIRHAM–NAOSIM was examined against broadband surface albedo measurements performed during the joint ACLOUD (Arctic CLoud Observations Using airborne measurements during polar Day) and PASCAL (Physical feedbacks of Arctic boundary layer, Sea ice, Cloud and AerosoL) campaigns, which were performed in May–June 2017 north of Svalbard. The SIS albedo parameterization was tested using measured quantities of the prognostic variables surface temperature and snow depth to calculate the surface albedo and the individual fractions of the ice surface subtypes (snow-covered ice, bare ice, and melt ponds) derived from digital camera images taken on board the Polar 5 and 6 aircraft. The selected low-altitude (less than 100 m) flight sections of overall 12 flights were performed over surfaces dominated by snow-covered ice. It was found that the range of parameterized SIS albedo for individual days is smaller than that of the measurements. This was attributed to the biased functional dependence of the SIS albedo parameterization on temperature. Furthermore, a time-variable bias was observed with higher values compared to the modeled SIS albedo (0.88 compared to 0.84 for 29 May 2017) in the beginning of the campaign, and an opposite trend towards the end of the campaign (0.67 versus 0.83 for 25 June 2017). Furthermore, the surface type fraction parameterization was tested against the camera image product, which revealed an agreement within 1 %. An adjustment of the variables, defining the parameterized SIS albedo, and additionally accounting for the cloud cover could reduce the root-mean-squared error from 0.14 to 0.04 for cloud free/broken cloud situations and from 0.06 to 0.05 for overcast conditions. |
format |
Text |
author |
Jäkel, Evelyn Stapf, Johannes Wendisch, Manfred Nicolaus, Marcel Dorn, Wolfgang Rinke, Annette |
spellingShingle |
Jäkel, Evelyn Stapf, Johannes Wendisch, Manfred Nicolaus, Marcel Dorn, Wolfgang Rinke, Annette Validation of the sea ice surface albedo scheme of the regional climate model HIRHAM–NAOSIM using aircraft measurements during the ACLOUD/PASCAL campaigns |
author_facet |
Jäkel, Evelyn Stapf, Johannes Wendisch, Manfred Nicolaus, Marcel Dorn, Wolfgang Rinke, Annette |
author_sort |
Jäkel, Evelyn |
title |
Validation of the sea ice surface albedo scheme of the regional climate model HIRHAM–NAOSIM using aircraft measurements during the ACLOUD/PASCAL campaigns |
title_short |
Validation of the sea ice surface albedo scheme of the regional climate model HIRHAM–NAOSIM using aircraft measurements during the ACLOUD/PASCAL campaigns |
title_full |
Validation of the sea ice surface albedo scheme of the regional climate model HIRHAM–NAOSIM using aircraft measurements during the ACLOUD/PASCAL campaigns |
title_fullStr |
Validation of the sea ice surface albedo scheme of the regional climate model HIRHAM–NAOSIM using aircraft measurements during the ACLOUD/PASCAL campaigns |
title_full_unstemmed |
Validation of the sea ice surface albedo scheme of the regional climate model HIRHAM–NAOSIM using aircraft measurements during the ACLOUD/PASCAL campaigns |
title_sort |
validation of the sea ice surface albedo scheme of the regional climate model hirham–naosim using aircraft measurements during the acloud/pascal campaigns |
publishDate |
2019 |
url |
https://doi.org/10.5194/tc-13-1695-2019 https://tc.copernicus.org/articles/13/1695/2019/ |
geographic |
Arctic Svalbard |
geographic_facet |
Arctic Svalbard |
genre |
albedo Arctic Sea ice Svalbard |
genre_facet |
albedo Arctic Sea ice Svalbard |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-13-1695-2019 https://tc.copernicus.org/articles/13/1695/2019/ |
op_doi |
https://doi.org/10.5194/tc-13-1695-2019 |
container_title |
The Cryosphere |
container_volume |
13 |
container_issue |
6 |
container_start_page |
1695 |
op_container_end_page |
1708 |
_version_ |
1766232261179473920 |