Ozone pollution and farm profits in England and Wales

Tropospheric ozone is an air pollutant known to adversely affect crop yields across Europe. Experimental work is underway to quantify yield effects at ambient ozone levels for a number of crops. In this article, we undertake direct, farm-level evaluation of the impact of ozone by estimating a multi-output profit function using a panel dataset of cereal farms in England and Wales. A system of equations, comprising the profit function, input and output share equations is estimated using a fixed-effects seemingly unrelated regression technique, with ozone as a quasi-fixed input. Estimated parameters are used to calculate tropospheric ozone-related profit and output supply elasticities. The main findings from the profit function show that a 10% increase in average ozone levels would decrease variable profits by 1.3% and wheat output supply by 1%. These results are of a significantly lower magnitude, but qualitatively consistent with findings from similar studies carried out in North America.