— February 13, 2018
Bruce D. Allen, Bureau of Geology field geologist, is studying the hydrology of the playa lakes in the Estancia basin in order to reconstruct major changes in climate that have affected this region in the past. Dr. Allen and researchers from the University of New Mexico have instrumented the playas with a network of meteorological stations and piezometers to track seasonal changes in climate and groundwater flow systems. By continuously collecting and interpreting data on solar radiation, atmospheric temperature, wind velocity, and changes in soil heat flux, an energy balance can be calculated that gives an estimate of evaporation. Piezometers provide information about hydraulic gradients that can be used to estimate ground-water discharge rates. From these data, hydrologic models can be calibrated for the modern drainage basin and climate system. Once these modern climatic/hydrologic analogs are created, they can be extended to simulate past climatic changes that included, during the past 20,000 years, episodes of more rainfall and colder climate which led to the expansion of an ancient lake covering 400 square miles in the basin.