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

N. Taniguchi (1) , S. Hayashida (1) , K. Takahashi (2) , Y. Matsumi (2)

1 Faculty of Science
2 STEL - Solar-Terrestrial Environment Laboratory [Nagoya]

The production yields of excited oxygen O(¹D) atoms from the near ultraviolet O₃ 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(¹D) quantum yields from O₃ 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(¹D) quantum yields on the stratospheric chemistry, the changes in stratospheric chemical partitioning and O₃ concentration are examined using a one-dimensional atmospheric model. Our steady state model simulations for 40° N in March indicate that the smaller O(¹D) quantum yields result in increases of stratospheric O₃ (up to ~2% in the upper stratosphere), which are attributed to the changes in HO_x, NO_x, and ClO_x abundance and their catalyzed O₃ loss rates.

Domaines: Océan, Atmosphère

N. Taniguchi, S. Hayashida, K. Takahashi, Y. Matsumi. Sensitivity studies of the recent new data on O(¹D) quantum yields in O₃ Hartley band photolysis in the stratosphere. Atmospheric Chemistry and Physics, 2003, 3 (5), pp.1293-1300. ⟨hal-00295323⟩