Please use this identifier to cite or link to this item:
http://hdl.handle.net/2122/4046
Authors: | Scarchilli, C.* Frezzotti, M.* Didonfrancesco, G.* Valt, M.* Urbini, S.* De Silvestri, L.* Dolci, S.* Iaccarino, A.* Grigioni, P.* |
Title: | The Impact of Precipitation and Sublimation Processes on Snow Accumulation: Preliminary Results | Journal: | Terra Antartica Reports | Series/Report no.: | / 14 (2008) | Publisher: | Terra Antartica Publication | Issue Date: | Jul-2008 | Keywords: | Sublimation processes Snow accumulation Mass balance |
Subject Classification: | 02. Cryosphere::02.02. Glaciers::02.02.02. Cryosphere/atmosphere Interaction 02. Cryosphere::02.02. Glaciers::02.02.06. Mass balance |
Abstract: | The need for climate change prediction has focused attention on the Surface Mass Balance (SMB) of the Antarctic continent and on how it influences the sea level. The SMB of the Antarctic plateau is governed by the equilibrium between precipitation and ablation processes such as sublimation and wind-borne snow redistribution. At scales of hundreds of kilometres snowfall variability dominates the snow accumulation process (Dery and Yau, 2002); at smaller scales, postdepositional process such as wind-borne redistribution, surface sublimation and snowdrift sublimation becomes more important. In recent years the sublimation phenomenon has received much attention from the glacial-meteorological community, and some theoretical studies have tried to model it (Bintanja, 1998; Dery & Yau, 2001b; Frezzotti, 2004). There are two different types of sublimation: surface sublimation and blowing snow sublimation. Surface sublimation is mostly determined by the continual exchange of water between the air (in the vapour phase) and the snow pack (in the solid phase) due to solar irradiance. Blowing snow sublimation is possibly the more effective of the two sublimation processes. It occurs when snow particles at the surface are blown by winds exceeding a certain threshold value. Particles suspended in the sub saturated Atmospheric Boundary Layer (ABL) sublimate at a relatively fast rate, cooling air mass transported by the wind and increasing the local atmospheric moisture content. When the first few meters of the ABL are completely saturated, the process is dumped. It takes a long time to meet this condition because katabatic winds transport saturated air masses to the coast, thereby reactivating sublimation. The role of sublimation in snow accumulation and its high variability at local scales are not fully understood due to the few available measurements in Antarctica. Further study and field experiments are required. |
Appears in Collections: | Article published / in press |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
TAR14_047_Scarchilli.pdf | main article | 245.07 kB | Adobe PDF | View/Open |
Page view(s) 20
289
checked on Apr 24, 2024
Download(s) 50
207
checked on Apr 24, 2024