Effects of water-table configuration on the planetary boundary layer over the San Joaquin River Watershed, California

While previous studies have examined the connections between soil moisture, groundwater, and the atmosphere, the atmospheric response to regional water-table drawdown has received less attention. To address this question, a coupled hydrologic-atmospheric model [Parallel Flow hydrologic model (ParFlow) and WRF] was used to simulate the San Joaquin River watershed of central California.

This study focuses specifically on the planetary boundary layer (PBL) in simulations with two imposed water-table configurations: a high water table mimicking natural conditions and a lowered water table reflecting historic groundwater extraction in California's Central Valley, although effect of irrigation was not simulated. An ensemble of simulations including three boundary layer schemes and six initial conditions was performed for both water-table conditions to assess conceptual and initial condition uncertainty.