Integrated GroundWater Modeling Center, Department of Geology and Geological Engineering, Colorado School of Mines, Golden, CO, USA.
Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY, USA.
Science. 2016 Jul 22;353(6297):377-80. doi: 10.1126/science.aaf7891.
Understanding freshwater fluxes at continental scales will help us better predict hydrologic response and manage our terrestrial water resources. The partitioning of evapotranspiration into bare soil evaporation and plant transpiration remains a key uncertainty in the terrestrial water balance. We used integrated hydrologic simulations that couple vegetation and land-energy processes with surface and subsurface hydrology to study transpiration partitioning at the continental scale. Both latent heat flux and partitioning are connected to water table depth, and including lateral groundwater flow in the model increases transpiration partitioning from 47 ± 13 to 62 ± 12%. This suggests that lateral groundwater flow, which is generally simplified or excluded in Earth system models, may provide a missing link for reconciling observations and global models of terrestrial water fluxes.
理解大陆尺度上的淡水通量将帮助我们更好地预测水文响应并管理我们的陆地水资源。将蒸散分为裸土蒸发和植物蒸腾仍然是陆地水平衡中的一个关键不确定性。我们使用综合水文模拟，将植被和土地能量过程与地表水和地下水文结合起来，研究大陆尺度上的蒸腾分配。潜在热通量和分配都与地下水位深度有关，在模型中包括侧向地下水流动会使蒸腾分配从 47±13%增加到 62±12%。这表明侧向地下水流动，通常在地球系统模型中被简化或排除，可能为协调陆地水通量的观测和全球模型提供一个缺失的环节。
