Framework (CCHF

TABLE 4.3 Process Representations Used in the Conceptual Cryosphere Hydrologic Framework (CCHF)

Process

Representation heat transfer enhanced temperature index (eti) with empirical glacier debris snow mass flux step based on temperature

ice flux ratio

snow albedo amount of incoming shortwave radiation that is absorbed at the snow or ice surface Short explanation main eti formulation follows Pellicciotti et al. (2005). impact of debris cover on ice heat transfer is an empirical representation derived from Kraaijenbrink et al. (2017). melt is allowed to occur when temperature is above an empirically derived value. heat first melts any snowpack present. if there is additional heat, the portion of the heat that melts ice is based on how much has been used to melt snow. this scales the modeled ice heat flux.

exerts a strong influence on the spatial and temporal evolution of melt rates. Based on Pellicciotti et al. (2005).

ice albedo

Black carbon impact on albedo constant

concentrations in snow and ice Debris-free and debris-covered albedos are based on broadly accepted values (DeWalle and rango 2008). empirically derived formula that modifies snow and ice albedo based on field experiments by ming et al. (2009).

snowpack moisture-holding capacity

Percentage the snowpack is modeled to hold an amount of water as an empirically derived portion of its total water-equivalent snow content. snow sublimation elevation dependent follows formulation by lutz et al. (2016). snow to ice Depth snow is assumed to become part of the ice when its depth is greater than a threshold.

snow avalanche angle snow avalanches for all spatial grid cells when the steepest angle is greater than a threshold.

runoff leaky bucket the top layer of ground acts as a “leaky bucket” with a maximum reservoir size and a set percentage that drains every time step. Based on moore, trubilowicz, and Buttle (2012).

top of atmosphere radiation DeWalle and rango method

atmospheric transmittance linear function of elevation solar radiation is modeled as a function of day of the year and grid attributes (latitude, aspect, slope). Based on DeWalle and rango (2008). more top of atmosphere radiation reaches the ground the higher the elevation. Based on coops, Wulder, and iwanicka (2009).

Source: the explanations contain the sources for each process.