title: Analytical solutions of travel time to a pumping well with variable evapotranspiration.
abstract: Analytical solutions of groundwater travel time to a pumping well in an unconfined aquifer have been developed in previous studies, however, the change in evapotranspiration was not considered. Here, we develop a mathematical model of unconfined flow toward a discharge well with redistribution of groundwater evapotranspiration for travel time analysis. Dependency of groundwater evapotranspiration on the depth to water table is described using a linear formula with an extinction depth. Analytical solutions of groundwater level and travel time are obtained. For a typical hypothetical example, these solutions perfectly agree with the numerical simulation results based on MODFLOW and MODPATH. As indicated in a dimensionless framework, a lumped parameter which is proportional to the pumping rate controls the distributions of groundwater evapotranspiration rate and the travel time along the radial direction.
authors.affiliation: Ministry of Education Key Laboratory of Groundwater Circulation and Evolution, China University of Geosciences, Beijing 100083, China; chentianfei1987@126.com.
authors.forename: Tian-Fei
authors.initials: TF
authors.lastname: Chen
authors.forename: Xu-Sheng
authors.initials: XS
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Wan
authors.forename: Hailong
authors.initials: H
authors.lastname: Li
mesh_terms: D060587:Groundwater; D008962:Models, Theoretical; D058438:Water Cycle; D014872:Water Movements; D060986:Water Wells