Some Aspects of Stratospheric Chemical Response to Solar Particle Precipitations: Potential Roles of N₂(A³Σ) and Ion-Chemistry

Abstract

Large amounts of long lived N₂(A ³Σ) are created by the energy degradation of precipitating solar particles. Laboratory data suggest that in the stratosphere N₂(A³Σ) are efficiently converted into N₂O. Through reactions with O(¹D), N₂O may gradually release NO and thereby influence the long term aspects of stratospheric chemical response. During the daytime, negative ions may transform an active NO_X into an inactive HNO₃. At night both negative and positive ion chemistry generate HO_X. Omission of ionic chemistry results in considerable underestimation of O₃ depletion during the initial phases of solar particle events, and thereby introduces significant error in the estimation of the nature of the prompt response. For further progress more refined model calculations as well as additional laboratory verification of some of the key assumptions are needed.