Health & Environmental Research Online (HERO)


Print Feedback Export to File
1605394 
Journal Article 
Role of NOy as a diagnostic of small-scale mixing in a denitrified polar vortex 
Gao, RS; Popp, PJ; Ray, EA; Rosenlof, KH; Northway, MJ; Fahey, DW; Tuck, AF; Webster, CR; Hurst, DF; Schauffler, SM; Jost, H; Bui, TP 
2002 
Yes 
Journal of Geophysical Research
ISSN: 0148-0227
EISSN: 2156-2202 
107 
D24 
4794 
WOS:000181259400011 
[1] Observations of three stratospheric species (N2O, CH4, and NOy) are examined for their suitability as mixing tracers in the inner Arctic vortex region between late February and mid-March 2000. NOy is highly inhomogeneous on isentropic surfaces and has little systematic vertical gradient between the 420 and 470 K potential temperature surfaces due to severe and extensive denitrification. Probability distribution functions of NOy calculated from in situ measurements do not show systematic and significant change as a function of time, indicating that mixing was too slow to substantially homogenize NOy distribution and therefore to strongly affect photochemical O-3 destruction rates during the period. We propose that the NOy inhomogeneity is useful for diagnosing small-scale, irreversible mixing rates during the measurement period. A simple kinematic model is used to show that the NOy standard deviation on an isentropic level in the vortex has desirable properties for quantifying these rates. A practical method for deriving mixing rates for chemistry and transport models has been proposed for future studies. 
small-scale mixing; NOy; polar vortex