Oxford MIPAS meeting#40
30 Sep 03

Present

Instrument Status [Prev] [Next] (Some details on the Envisat Web-Site)

Instrument Reports

L2 Data [Prev] [Next]
In /home/crun/eodg/mipas/L2/ [Plots of profile locations]

30km Zonal Mean Traces (AD) [Next]
Following the change in L2 profiles due to gain problems it has been decided to monitor ESA L2 data quality on a daily rather than just a monthly, basis in order to detect similar problems more rapidly in future.
Monitoring is by plotting the time series of the zonally averaged values retrieved at the 30km nominal tangent point. Results maintained on: http://www.atm.ox.ac.uk/group/mipas/day/

OPTIMO Retrievals (CP) [Prev] [Next]
Using the Oxford processor to retrieve MIPAS pT, O3 and H2O profile data during the split Antarctic vortex period, 8Sep- mid-October.

RAL Retrievals (VJ) [Prev] [Next]
About to start processing an orbit of data with RAL code (1D) to retrieve O3 and H2O jointly (using ESA L2 pT). Looking for a suitable orbit.

Joint pT, O3, H2O Microwindows (AD) [Prev] [Next]
Still in the process of selecting sets of microwindows of 1cm-1, 2cm-1 and 3cm-1 max width for global, joint retrievals.
Results so far (solid symbols on plots are accuracy profiles, open symbols are precision)
Individual retrievals for comparison (these are the occupation matrices using existing microwindows for retrievals extended down to 6km), 14 MWs, 8177 pts, 158 bits.
It is fairly clear that, computationally, joint retrievals are much more efficient in terms of information retrieved per measurement used, (and probably that narrow microwindows are better than wide microwindows unless the computation overhead per microwindow becomes significant).

AMIL2DA [Prev]
JGR Blind Test Retrieval Intercomparison paper - Now accepted for publication

ASSFTS-11 Workshop (8-10th Oct, Bad Wildbad, Germany) [Prev] [Next]
Following MIPAS posters/presentations
Email sent to ACVT by Rob Koopman, ESA 18 Sep 2003. Email 
Dear colleagues,

As independently reported by Dominiq Fonteijn and Antje Dethof, MIPAS data from
the interval in subject suffer from significant bias (temperature bias of 5
Kelvin, propagating into errors on all trace gases). QWG analysis indicates
that this sharp discontinuity in data quality is due to the decontamination
that occurred during the unplanned payload switch off on 4 September 2003
22:52.  The operations of the MIPAS have resumed on 8 September 12:52 (orbit
7965), and subsequent higher-level data produced until the gain calibration
activated on 17 September (orbit 8090) should be discarded. The gain
calibration applied to these post-switch-off data was actually representative
of ice-deposition conditions valid only before the cooler switch off.  A
gain-calibration file
(MIP_CG1_AXVIEC20030916_150054_20030909_071411_20080916_121108) has now been
activated that will ensure correct calibration during future reprocessing of
data from this interval.