Resumen
Direct measurements of the rate of NO2 photolysis to NO and 0(3P) are reported as photolysis frequencies J(NO2) for Mexico City. These frequencies were measured using a flow reactor, where a known concentration of NO2 was photolysed for different experimental exposure times. UV radiation was measured with an Eppley UV radiometer. Comparisons with calculated values using a radiation transfer model, and Madronich's formula are shown.