000029593 001__ 29593
000029593 041__ $$aEnglish
000029593 100__ $$aGilbert, A.
000029593 245__ $$aModeling near-Surface Firn Temperature in a Cold Accumulation Zone (Col Du Dôme, French Alps): From a Physical to a Semi-Parameterized Approach
000029593 269__ $$cMay 2014
000029593 260__ $$c2014
000029593 300__ $$a689-703
000029593 507__ $$aPatrick Wagnon, ICIMOD staff, peerreviewed
000029593 511__ $$aCrysparticle
000029593 520__ $$aAnalysis of the thermal regime of glaciers is crucial for glacier hazard assessment, especially in the context of a changing climate. In particular, the transient thermal regime of cold accumulation zones needs to be modeled. A modeling approach has therefore been developed to determine this thermal regime using only near-surface boundary conditions coming from meteorological observations. In the first step, a surface energy balance (SEB) model accounting for water percolation and radiation penetration in firn was applied to identify the main processes that control the subsurface temperatures in cold firn. Results agree well with subsurface temperatures measured at Col du Dôme (4250 m above sea level (a.s.l.)), France. In the second step, a simplified model using only daily mean air temperature and potential solar radiation was developed. This model properly simulates the spatial variability of surface melting and subsurface firn temperatures and was used to accurately reconstruct the deep borehole temperature profiles measured at Col du Dôme. Results show that percolation and refreezing are efficient processes for the transfer of energy from the surface to underlying layers. However, they are not responsible for any higher energy uptake at the surface, which is exclusively triggered by increasing energy flux from the atmosphere due to SEB changes when surface temperatures reach 0 °C. The resulting enhanced energy uptake makes cold accumulation zones very vulnerable to air temperature rise.
000029593 700__ $$aVincent, C.
000029593 700__ $$aSix, D.
000029593 700__ $$aWagnon, P.
000029593 700__ $$aPiard, L.
000029593 700__ $$aGinot, P.
000029593 773__ $$pThe Cryosphere
000029593 773__ $$v8 (2)
000029593 773__ $$a10.5194/tc-8-689-2014
000029593 8564_ $$uhttp://www.the-cryosphere.net/8/689/2014/$$yExternal link
000029593 888__ $$ahttp://www.the-cryosphere.net/8/689/2014/tc-8-689-2014.pdf
000029593 980__ $$aARTICLE