Reply on RC1

Abstract

<strong class="journal-contentHeaderColor">Abstract.</strong> The climate in Northeast Greenland is shaped by complex topography and interaction with the cryosphere. To capture this complexity, we use an observational dataset from the Zackenberg region (ZR), (Northeast Greenland) to investigate the local and large-scale factors that determine the slope temperature gradients (STGs) i.e., the temperature gradient along the mountain slope. A synthesis of automated weather stations, reanalysis, and regional climate model were used. Our results show that the surface type and near fjord-ice condition are the dominating factors governing the temporal evolution of the STGs in the ZR. Considering large-scale drivers of STG, we find that shallow, i.e., more positive (inversions) or less negative than the mean condition, STGs are associated with a positive anomaly in geopotential height at 500 hPa and surface pressure over East Greenland. A strong connection between fractional sea-ice cover (SIF) in the Greenland Sea and the terrestrial climate of the ZR is found. Evidently, a positive SIF anomaly coincides with shallow STG since the temperature at the bottom of the valley decreases more than at the top. For example, the mean STG varies by ~4 &ordm;C km^&minus;1 for a corresponding ~27 % change in SIF. Changing temperatures and precipitation patterns related to SIF variability also affect the surface mass balance (SMB) of the nearby A. P. Olsen Ice Cap. During summer, days with high SIF are associated with a positive SMB anomaly in the ablation area (~16 mm w.e. day^&minus;1; indicating less melt) and a negative anomaly in the accumulation area (~&minus;0.3 mm w.e. day^&minus;1; indicating less accumulation). The decrease in temperature and snowfall related to the days with high SIF explain this opposite pattern in the ablation and accumulation area.