![]() ![]() Although of unrivalled interest for studying blowing snow over large temporal, horizontal and vertical scales simultaneously, satellite lidar data provide snapshots of a particular set of blowing-snow properties (frequency, layer depth, optical thickness) relative to the satellite revisit time ( Palm et al., 2011). Déry et al., 1998 Bintanja, 2000 Amory et al., 2016), model results as well as the assumptions made in the implementation of wind-driven snow physics need to be carefully assessed with independent observations.Īdvances in active lidar remote sensing of the atmosphere from space have provided recent insights into the spatial distribution and temporal variability in blowing snow over the last decade independently of modelling approaches. Considering the diversity of interactions and the non-linearity of processes involved in the onset, development and magnitude of wind-driven snow occurrences (e.g. ( 2019) exhibit a similar overall spatial pattern but are more than 3 times larger than those reported in van Wessem et al. Modelled snow mass fluxes presented in Agosta et al. The latest continent-wide estimations of wind-driven snow sublimation obtained from regional modelling ( van Wessem et al., 2018) are lower by a factor of 4 than those computed from a combination of satellite products and meteorological reanalyses ( Palm et al., 2017). Conversely, contrasting results can be found from one study to another in the absolute values attributed to the contribution of wind-driven snow processes to the large-scale mass transport. A consensus emerging from these efforts that has persisted for more than 2 decades suggests that, although significant locally, mass loss through wind redistribution and export into the ocean is of minor importance, while sublimation during transport remains the dominant sink of mass when evaluated over the whole ice sheet. Mann et al., 2000 Bintanja, 2001 Thiery et al., 2012).īecause of the widespread character of drifting and blowing snow over the vast and remote Antarctic continent, estimates of their hydrological and climatological significance at the ice-sheet scale rely on parameterized methods (e.g. ![]() Sublimation of snow particles during transport is a major component of the surface heat and moisture budgets in regions, where most of the precipitated snow is relocated by wind (e.g. In coastal areas, wind redistribution of snow is responsible for an export of mass beyond the ice-sheet margins ( Scarchilli et al., 2010 Palm et al., 2017). Erosive winds redistribute snow at the surface and can form areas of near-zero net accumulation (known as wind glaze areas) or even net ablation (known as blue ice areas), whose presence has a profound influence on the local surface energy balance ( Bintanja, 1999 Scambos et al., 2012), possibly enhancing surface melt ( Lenaerts et al., 2017). Wind-driven transport of snow in Antarctica, organized into drifting ( 2 m a.g.l.) snow, has important implications for the ice-sheet climate and surface mass balance. The dataset is freely available to the scientific community and can be used to complement satellite products and evaluate snow-transport models close to the surface and at high temporal frequency. This paper presents an assessment of drifting-snow occurrences and snow mass transport from up to 9 years (2010–2018) of half-hourly observational records collected in one of the Antarctic regions most prone to snow transport by wind. within 2 m) measurements of drifting snow currently available over the Antarctic continent. The data, provided nearly continuously so far, constitute the longest dataset of autonomous near-surface (i.e. With the aim of acquiring new data relevant to the observation and modelling of drifting snow in Antarctic conditions, two remote locations in coastal Adélie Land (East Antarctica) that are 100 km apart were instrumented in January 2010 with meteorological and second-generation IAV Engineering acoustic FlowCapt™ sensors. While field measurements are needed to evaluate and interpret model and satellite products, most drifting-snow observation campaigns in Antarctica involved data collected at a single location and over short time periods. Drifting snow is a widespread feature over the Antarctic ice sheet, whose climatological and hydrological significance at the continental scale have been consequently investigated through modelling and satellite approaches. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |