Abstract. Retrievals of temperature, H₂O, O₃, HNO₃, CH₄, N₂O, ClONO₂ and ClO from MIPAS reduced spectral resolution nominal mode limb emission measurements outperform retrievals from respective full spectral resolution measurements both in terms of altitude resolution and precision. The estimated precision (including measurement noise and propagation of uncertain parameters randomly varying in the time domain) and altitude resolution are typically 0.5–1.4 K and 2–3.5 km for temperature between 10 and 50 km altitude, and 5–6%, 2–4 km for H₂O below 30 km altitude, 4–5%, 2.5–4.5 km for O₃ between 15 and 40 km altitude, 3–8%, 3–5 km for HNO₃ between 10 and 35 km altitude, 5–8%, 2–3 km for CH₄ between 15 and 35 km altitude, 5–10%, 3 km for N₂O between 15 and 35 km altitude, 8–14%, 2.5–9 km for ClONO₂ below 40 km, and larger than 35%, 3–7 km for ClO in the lower stratosphere. As for the full spectral resolution measurements, the reduced spectral resolution nominal mode horizontal sampling (410 km) is coarser than the horizontal smoothing (often below 400 km), depending on species, altitude and number of tangent altitudes actually used for the retrieval. Thus, aliasing might be an issue even in the along-track domain. In order to prevent failure of convergence, it was found to be essential to consider horizontal temperature gradients during the retrieval.