MIPAS: an instrument for atmospheric and climate research

[摘要] MIPAS, the Michelson Interferometer for Passive Atmospheric Sounding, is amid-infrared emission spectrometer which is part of the core payload ofENVISAT. It is a limb sounder, i.e. it scans across the horizon detectingatmospheric spectral radiances which are inverted to vertical temperature,trace species and cloud distributions. These data can be used for scientificinvestigations in various research fields including dynamics and chemistryin the altitude region between upper troposphere and lower thermosphere.

The instrument is a well calibrated and characterized Fourier transformspectrometer which is able to detect many trace constituents simultaneously.The different concepts of retrieval methods are described includingmulti-target and two-dimensional retrievals. Operationally generated datasets consist of temperature, H₂O, O₃, CH₄, N₂O,HNO₃, and NO₂ profiles. Measurement errors are investigated indetail and random and systematic errors are specified. The results arevalidated by independent instrumentation which has been operated at groundstations or aboard balloon gondolas and aircraft. Intercomparisons of MIPASmeasurements with other satellite data have been carried out, too. As aresult, it has been proven that the MIPAS data are of good quality.

MIPAS can be operated in different measurement modes in order to optimizethe scientific output. Due to the wealth of information in the MIPASspectra, many scientific results have already been published. They includeintercomparisons of temperature distributions with ECMWF data, thederivation of the whole NO_y family, the study of atmospheric processesduring the Antarctic vortex split in September~2002, the determination ofproperties of Polar Stratospheric Clouds, the downward transport of NO_x inthe middle atmosphere, the stratosphere-troposphere exchange, the influenceof solar variability on the middle atmosphere, and the observation ofNon-LTE effects in the mesosphere.

[学科分类] 大气科学