As stated previously, there is considerable uncertainty in the input rate of odd nitrogen (N and NO) species from the martian ionosphere to the neutral atmosphere (Krasnopolsky, 1993). In his own model of the neutral atmosphere, Krasnopolsky considers cases both with and without input of odd nitrogen from the upper atmosphere (Krasnopolsky, 1993). We vary the input of N and NO into the model, using the nominal case as an upper limit. As these values are decreased, the pernitrate deposition flux drops, which is shown in Fig. 5. The lowest input of odd nitrogen corresponds to 3.5–6.1 (×10−4) wt.% N accumulated over 3 byr and mixed into 1.5–2.6 m of soil.
N
input of odd nitrogen
3.5–6.1 (×10−4) wt.%
wt.%
input of odd nitrogen
accumulated
over 3 byr
byr
soil
1.5–2.6 m
m