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A state‐space model (SSM) of infiltration estimates daily groundwater recharge using time‐series of groundwater‐level altitude and meteorological inputs (liquid precipitation, snowmelt, and evapotranspiration). The model includes diffuse and preferential flow through the unsaturated zone, where preferential flow is a function of liquid precipitation and snowmelt rates and a threshold rate, above which there is direct recharge to the water table. Model parameters are estimated over seasonal periods and the SSM is coupled with the Kalman Filter (KF) to assimilate recent observations (hydraulic head) and meteorological inputs into recharge estimates. The approach can take advantage of real‐time hydrologic and meteorological data to deliver real‐time recharge estimates. The model is demonstrated on daily observations from two bedrock wells in carbonate aquifers of northwestern New York (USA) between 2013 and 2018. Meteorological inputs for liquid precipitation and snowmelt are compiled from SNODAS (2021). Results for recharge during winter and spring seasons show preferential flow events to the water table from liquid precipitation, snowmelt, or a combination of the two. Recharge estimates summed annually are consistent with previous estimates of recharge reported from groundwater flow and surface‐process models. Results from the SSM and KF point to errors in meteorological inputs, such as the snowmelt rate, that are not compatible with hydraulic head observations. Whereas liquid and solid precipitation are measured at discrete stations and extrapolated to 1‐km2 grid cells, snowmelt is a meteorological modeled outcome that may not represent conditions in the vicinity of monitoring well locations. Article Impact Statement: A state‐space model interprets time‐series of water table altitude, precipitation, and snowmelt to estimate groundwater recharge. [ABSTRACT FROM AUTHOR]

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The sixty-eighth annual business meeting of the American Economic Association was called to order in the hotel Commodore, New York. at 5:10 p.m. by president John P. Black. The minutes of the business meeting of December 30, 1954, were approved, actions of the 1955 executive committee ratified, and the reports of the officers and committees accepted. All minutes and reports are published in the "Proceedings." High lights of the year's activities were described by secretary-treasurer James Washington Bell, who also presented an account of the financial operations, investment holdings, and the present condition of the Association's finances. He called attention to the narrow balance between operating income and expenses and indicated the identity of the profit taken on sale of securities and the amount of the year's surplus income. Despite increased expenses, it still appears possible to maintain a balanced budget with $6.00 dues. The managing editor of the journal "American Economic Review," Bernard F. Haley, reviewed the operations of the Review office and the work of the editorial board. This report is presented in full in the "Proceedings."