Topographic controls on soil moisture scaling properties in polygonal ground using idealized high-resolution surface–subsurface simulations

摘要: Microtopographic features, such as polygonal ground, are characteristic sources of landscape heterogeneity in the Alaskan Arctic coastal plain. Here, we analyze hypothesis that microtopography is a dominant controller soil moisture landscapes. We perform multi-year surface–subsurface isothermal flow simulations using PFLOTRAN model for summer months at six spatial resolutions (0.25–8 m, increments factor 2). Simulations performed four study sites near Barrow, Alaska part NGEE-Arctic project. Results indicate non-linear scaling relationship statistical moments moisture. Mean all accurately captured coarser resolution simulations, but variance significantly under-estimated simulations. The decrease greater than obtained by coarsening out fine also develop relationships to estimate fine-resolution probability distribution function (PDF) coarse and topography. Although estimated PDF underestimated during very wet conditions, computed from inferred had good agreement with full solutions (bias 0.99) sites. Lastly, two spatially-explicit methods downscale coarse-resolution first downscaling method requires simulation resolution, while second approach uses only topographical information resolutions. Both approaches able patterns when compared (mean error < ± 1 %), more estimates variance.