Validation of MIPAS-ENVISAT NO 2 operational data

摘要: The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument was launched aboard the environmental satellite ENVISAT into its sun-synchronous orbit on 1 March 2002. short-lived species NO 2 is one of key target products MIPAS that are operationally retrieved from limb emission spectra measured in stratosphere and mesosphere. Within validation activities, a large number independent observations balloons, satellites ground-based stations have been compared to European Space Agency (ESA) version 4.61 operational data comprising time period July 2002 until 2004 where with full spectral resolution. Comparisons between balloon-borne carried out 2003 Arctic, at mid-latitudes, tropics show very good agreement below 40 km altitude mean deviation roughly 3%, virtually without any significant bias. comparison ACE exhibits only small negative bias which appears not be significant. instruments HALOE, SAGE II, POAM III confirm common spring-summer Arctic positive Antarctic middle upper exceeding frequently combined systematic error limits. In contrast ESA processor, IMK/IAA retrieval code allows accurate inference volume mixing ratios under consideration all important non-LTE processes. Large differences both results appear especially higher altitudes, above about 50 55 km. These might explained least partly by polar winter conditions but mid-latitudes. Below this region processors remain within 5% (during night) up 10% day) undisturbed (September 2002) 40% perturbed night (February 2004). intercomparison NDACC shows no FTIR measurements Kiruna (68° N) summer larger deviations autumn winter. over whole remains 10%. A 15% daytime 8% nighttime has determined UV-vis comparisons Harestua (60° N). Results pole-to-pole DOAS/UV-visible sunrise mid-morning column shown falls accuracy limit method. Altogether, it can indicated profiles yield valuable information vertical distribution lower (below 45 km) during day an overall 10–20% precision typically 5–15% such useful scientific studies. cases extremely high occurs mesosphere (polar winter) less than atmospheric conditions.