A two-dimensional model of odd-nitrogen in the thermosphere and mesosphere

Satellite measurements of the global nitric oxide distribution
demonstrating the need for a two dimensional model of odd nitrogen
photochemistry and transport in the thermosphere and mesosphere are
reviewed. The main characteristics of a new code solving the transport
equation for N(4S), N(2D), and N0 are given. This model extends from
pole to pole between 75 and 275 km and reacts to the magnetic activity,
the ultraviolet solar flux, and the neutral wind field. The effects of
ionization and subsequent odd nitrogen production by high latitude
particle precipitation are also included. Preliminary results are
illustrated for a magnetically quiet solar minimum period with no
neutral wind.