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Within the setup of a long‐term irrigation experiment in a Scots pine (Pinus sylvestris) forest at Pfynwald in the inner-Alpine Swiss Rhone valley, ecophysiological data were recorded from permanently irrigated trees, from trees cut off the irrigation after 11 years, and non-treated control trees. The data sets include continuous stem radius changes (automated point dendrometer at breast height), tree stem sap flow (Granier-type sap flow sensors at breast height), air temperature and humidity, vapour pressure deficit, net solar radiation, precipitation (tipping bucket), and volumetric soil water content (TDR and HS-sensors). The meteorological data were measured 2 m above the canopy in about 13 m height on top of a scaffold. The soil water sensors covered soil depth of up to 80 cm. Data resolution is 1 hour or higher and covers the years 2011-2017. Data as used and published in Zweifel, et al. (2020), Determinants of legacy effects in pine trees ‐ implications from an irrigation‐stop experiment. New Phytol. doi:10.1111/nph.16582

Computer models are necessary for understanding and predicting marine ice sheet behaviour. However, there is uncertainty over implementation of physical processes at the ice base, both for grounded and floating glacial ice. Here we implement several sliding relations in a marine ice sheet flow-line model accounting for all stress components and demonstrate that model resolution requirements are strongly dependent on both the choice of basal sliding relation and the spatial distribution of ice shelf basal melting.Sliding relations that reduce the magnitude of the step change in basal drag from grounded ice to floating ice (where basal drag is set to zero) show reduced dependence on resolution compared to a commonly used relation, in which basal drag is purely a power law function of basal ice velocity. Sliding relations in which basal drag goes smoothly to zero as the grounding line is approached from inland (due to a physically motivated incorporation of effective pressure at the bed) provide further reduction in resolution dependence.A similar issue is found with the imposition of basal melt under the floating part of the ice shelf: melt parameterisations that reduce the abruptness of change in basal melting from grounded ice (where basal melt is set to zero) to floating ice provide improved convergence with resolution compared to parameterisations in which high melt occurs adjacent to the grounding line.Thus physical processes, such as sub-glacial outflow (which could cause high melt near the grounding line), impact on capability to simulate marine ice sheets. If there exists an abrupt change across the grounding line in either basal drag or basal melting, then high resolution will be required to solve the problem. However, the plausible combination of a physical dependency of basal drag on effective pressure, and the possibility of low ice shelf basal melt rates next to the grounding line, may mean that some marine ice sheet systems can be reliably simulated at a coarser resolution than currently thought necessary.