dc.contributor.author | Dachauer, Armin | |
dc.contributor.author | Hann, Richard | |
dc.contributor.author | Hodson, Andrew | |
dc.date.accessioned | 2022-03-07T12:45:06Z | |
dc.date.available | 2022-03-07T12:45:06Z | |
dc.date.created | 2021-12-09T10:32:23Z | |
dc.date.issued | 2021 | |
dc.identifier.citation | Dachauer, A., Hann, R., & Hodson, A. J. (2021). Aerodynamic roughness length of crevassed tidewater glaciers from UAV mapping. The Cryosphere, 15(12), 5513-5528. | en_US |
dc.identifier.issn | 1994-0416 | |
dc.identifier.uri | https://hdl.handle.net/11250/2983426 | |
dc.description.abstract | The aerodynamic roughness length (z_0) is an important parameter in the bulk approach for calculating turbulent fluxes and their contribution to ice melt. However, z_0 estimates for heavily crevassed tidewater glaciers are rare or only generalised. This study used uncrewed aerial vehicles (UAVs) to map inaccessible tidewater glacier front areas. The high-resolution images were utilised in a structure-from-motion photogrammetry approach to build digital elevation models (DEMs). These DEMs were applied to five models (split across transect and raster methods) to estimate z_0 values of the mapped area. The results point out that the range of z_0 values across a crevassed glacier is large, by up to 3 orders of magnitude. The division of the mapped area into sub-grids (50 m × 50 m), each producing one z_0 value, accounts for the high spatial variability in z_0 across the glacier. The z_0 estimates from the transect method are in general greater (up to 1 order of magnitude) than the raster method estimates. Furthermore, wind direction (values parallel to the ice flow direction are greater than perpendicular values) and the chosen sub-grid size turned out to have a large impact on the z_0 values, again presenting a range of up to 1 order of magnitude each. On average, z_0 values between 0.08 and 0.88 m for a down-glacier wind direction were found. The UAV approach proved to be an ideal tool to provide distributed z_0 estimates of crevassed glaciers, which can be incorporated by models to improve the prediction of turbulent heat fluxes and ice melt rates. | en_US |
dc.language.iso | eng | en_US |
dc.publisher | Copernicus Publications | en_US |
dc.rights | Navngivelse 4.0 Internasjonal | * |
dc.rights.uri | http://creativecommons.org/licenses/by/4.0/deed.no | * |
dc.title | Aerodynamic roughness length of crevassed tidewater glaciers from UAV mapping | en_US |
dc.type | Peer reviewed | en_US |
dc.type | Journal article | en_US |
dc.description.version | publishedVersion | en_US |
dc.rights.holder | © Author(s) 2021. | en_US |
dc.source.pagenumber | 5513-5528 | en_US |
dc.source.volume | 15 | en_US |
dc.source.journal | The Cryosphere | en_US |
dc.source.issue | 12 | en_US |
dc.identifier.doi | 10.5194/tc-15-5513-2021 | |
dc.identifier.cristin | 1966558 | |
dc.relation.project | Norges forskningsråd: 223254 | en_US |
dc.relation.project | Norges forskningsråd: 294764 | en_US |
dc.relation.project | Norges forskningsråd: 296355 | en_US |
cristin.ispublished | true | |
cristin.fulltext | original | |
cristin.qualitycode | 2 | |