Oxford MIPAS meeting#136
25 Mar 08

Summary extracted from the Feb08 Monthly Report

• MIPAS is back to full-time mission (100% duty cycle) since 1st December 2007.
• The MIPAS level 1 NRT processing was restarted on 1st February at Kiruna and ESRIN stations, the products are available via ftp. The daily monitoring of L1 NRT was also restarted and daily reports are available on the pcs web site.
• During the reporting month MIPAS performed very well, in fact only 2 IDU errors were recorded, however the instrument was switched off for about 9h during 11th February due to a planned OCM (see §2.2.2).
• The Baseline scenario for 100% duty cycle was planned; it consists of the following schema: 8 days NOM + 1 day MA + 1 day UA. A more detailed description of the instrument planning for the reporting month can be found in §2.2.1.
• The availability of the instrument was very high (98.25% of the planned time) due to very good performances of the interferometer. The measurement segments not processed to L0 due to failures in the PDS were less than 1% of the planned measurement time (see § 2.2.4).
• The long term analysis of L0 data availability shows the increased duty cycle since April 2006 and highlights the improved instrument performances in the last year (see §2.2.4.2).
• The availability of L1 D-PAC products with respect to the expected time is around 95% in the last months (see §2.2.5).
• The instrument temperatures are stable during the reporting month, the variations are in the range of 1 – 2 K (see § 2.3.1).
• The cooler performs well during the reporting month; the vibrations were well below the warning level of 8 mg (see § 2.3.3).
• The long term trend of ADC max counts in channel A1 shows a strong correlation with the instrument self-emission and with the detector ice contamination. During the reporting month the ADC counts slightly decrease following the variation of the instrument temperature (see §2.3.4).
• The monitoring of the spectral correction factor shows a slight decreasing trend; nevertheless the variations over more than two years of operations are really small (∼ 2 ppm). The observed spreading of the points is due to the noise in the determination of this parameter (see § 2.4.2).
• The gain weekly increase during the reporting month is nominal, the maximum of gain increase in all the MIPAS bands remains well below the acceptance criterion of 1%/week (see § 2.4.3.1).
• The analysis of the accumulated gain allows monitoring the level of detector ice contamination. During the last months we observed a decreasing slope of the gain curve, showing that the detector is more and more “ice-free”. This is due to the better performances of the cooler obtained with more frequent decontamination (see §2.4.3.2).
• The absolute mispointing is stable around a value of -25mdeg. The seasonal variations of the pointing error are small and below the fixed threshold of 8mdeg. Less and less stars are available in the last months for the LOS calibration, as a result the mispointing estimation is becoming less precise (see §2.4.4).