This study analyzed summer observations of diurnal and seasonal surface energy budgets across several monitoring sites within the Arctic tundra underlain by permafrost. The Maximum Entropy Production (MEP) model was tested as a parsimonious model for estimating surface heat fluxes in data-sparse permafrost environments. Using net radiation, surface temperature, and a single parameter characterizing thermal inertia, the MEP model estimates latent, sensible, and ground heat fluxes that closely match observations at five sites with detailed flux data. The MEP potential evapotranspiration (PET) model reproduces estimates of the Penman-Monteith PET model, which requires multiple input variables. The MEP model is efficient and suitable for permafrost regions, as it does not require data on wind speed, surface roughness, or vertical gradients of temperature and vapor pressure. It also performs well in data-sparse areas, accurately estimating surface energy budgets. The study found that latent and sensible heat fluxes are nearly equal in Arctic permafrost tundra regions, with ground heat flux entering the subsurface during short summer intervals, leading to seasonal thaw. The MEP model accurately estimates surface heat fluxes and provides a complete surface energy budget partition with minimal input data. The model is particularly useful in the Arctic, where field observations are sparse and ground heat flux measurements are challenging. The MEP model is shown to be a viable alternative to traditional models for estimating surface energy budgets in data-sparse regions. The study highlights the importance of accurate measurements and constraints of ground heat flux in the Arctic. The MEP model is effective in estimating surface energy budgets and has potential for application in sparsely monitored Arctic areas.This study analyzed summer observations of diurnal and seasonal surface energy budgets across several monitoring sites within the Arctic tundra underlain by permafrost. The Maximum Entropy Production (MEP) model was tested as a parsimonious model for estimating surface heat fluxes in data-sparse permafrost environments. Using net radiation, surface temperature, and a single parameter characterizing thermal inertia, the MEP model estimates latent, sensible, and ground heat fluxes that closely match observations at five sites with detailed flux data. The MEP potential evapotranspiration (PET) model reproduces estimates of the Penman-Monteith PET model, which requires multiple input variables. The MEP model is efficient and suitable for permafrost regions, as it does not require data on wind speed, surface roughness, or vertical gradients of temperature and vapor pressure. It also performs well in data-sparse areas, accurately estimating surface energy budgets. The study found that latent and sensible heat fluxes are nearly equal in Arctic permafrost tundra regions, with ground heat flux entering the subsurface during short summer intervals, leading to seasonal thaw. The MEP model accurately estimates surface heat fluxes and provides a complete surface energy budget partition with minimal input data. The model is particularly useful in the Arctic, where field observations are sparse and ground heat flux measurements are challenging. The MEP model is shown to be a viable alternative to traditional models for estimating surface energy budgets in data-sparse regions. The study highlights the importance of accurate measurements and constraints of ground heat flux in the Arctic. The MEP model is effective in estimating surface energy budgets and has potential for application in sparsely monitored Arctic areas.