Characterization of model errors in the calculation of tangent heights for atmospheric infrared limb measurements
- 1Dipartimento di Fisica e Astronomia, Università di Bologna, Bologna, Italy
- 2Istituto di Fisica Applicata "Carrara", Consiglio Nazionale delle Ricerche, Florence, Italy
- 3Istituto per le Applicazioni del Calcolo, Consiglio Nazionale delle Ricerche, Florence, Italy
Abstract. We review the main factors driving the calculation of the tangent height of spaceborne limb measurements: the ray-tracing method, the refractive index model and the assumed atmosphere. We find that commonly used ray tracing and refraction models are very accurate, at least in the mid-infrared. The factor with largest effect in the tangent height calculation is the assumed atmosphere. Using a climatological model in place of the real atmosphere may cause tangent height errors up to ± 200 m. Depending on the adopted retrieval scheme, these errors may have a significant impact on the derived profiles.