Sensitivity studies of the recent new data on O(1D) quantum yields in O3 Hartley band photolysis in the stratosphere

The production yields of excited oxygen O(D-1) atoms from the near ultraviolet O-3 photolysis are essential quantities for atmospheric chemistry calculations because of its importance as major sources of hydroxyl (OH) radicals and nitric oxide (NO). Recently, new O(D-1) quantum yields from O-3 photolysis between 230 and 305 nm in the Hartley band region were reported, which are almost independent of the photolysis wavelength (0.88-0.93) and smaller than NASA/JPL-2000 recommendations (0.95 between 240 and 300 nm). In order to assess consequences of the new data of O(D-1) quantum yields on the stratospheric chemistry, the changes in stratospheric chemical partitioning and O-3 concentration are examined using a one-dimensional atmospheric model. Our steady state model simulations for 40degrees N in March indicate that the smaller O(D-1) quantum yields result in increases of stratospheric O-3 (up to similar to2% in the upper stratosphere), which are attributed to the changes in HOx, NOx, and ClOx abundance and their catalyzed O-3 loss rates.