"What's new" Archive: 2008

08 May 2008: MLS v2.2 reprocessing complete
Contact: Nathaniel Livesey

As of 02 May 2008, version 2.2 reprocessing of all Aura Microwave Limb Sounder (MLS) data has completed. This reprocessing has covers the period from the July 2004 Aura launch to the present date. v2.2 data should be used in preference to the earlier v1.5 data.

For more information on MLS v2.2 data, and on improvements over the earlier v1.5, please refer to the MLS 'Version 2.2 Level 2 Data Quality Document' available from the MLS data page, under the 'Data Documentation' link. Dedicated validation papers for the individual products have also been published in the Aura validation special issue of JGR- Atmospheres, and reprints are available from the MLS publications page.

MLS data can be downloaded from the GSFC-DISC (http://disc.gsfc.nasa.gov, or follow the 'Order MLS Data' link on the MLS home page). If you have any questions about MLS data, please contact the MLS science team member(s) responsible for the products of interest, as detailed in the data quality document.
13 April 2008: MLS data algorithm update
Contact: Nathaniel Livesey

The MLS data processing algorithms have recently been updated to version v02.23. The only changes between v02.22 and v02.23 are modifications to the level 1 (radiance calibration) software to handle two separate issues. The first modification is in response to a change in operation of the MLS THz laser local oscillator on January 28, 2008, which resulted in a dramatic reduction in the number of useful level 2 (geophysical product data) OHprofiles in v02.22 (because of data quality control screening that was too conservative). When (re)processed with v02.23 algorithms, these days will have the typical (~90%) fraction of useful profiles for OH. The second modification is better handling of occasional (0.001%) corrupted instrument data packets arising from an ongoing anomaly with the Aura spacecraft data handling system commencing on December 4, 2007. The impact of this change on level 2 data is minimal. There is no need to reprocess data prior to December 2007 unaffected by either issue, and - for simplicity - the few remaining (2004) days still to be reprocessed to v02.2x are being run using v02.22.

12 February 2008: Aura Spacecraft FMU Anomaly Dates
Contact: David Cuddy

In December 2007, the Aura Spacecraft experienced anomalies with its FMU. These anomalies effected the output of spacecraft attitude data used in standard MLS processing. The attitude data has been re-processed using S-Band data as its source and below is a table of times and dates for which we received this updated attitude data. Users of Level 2 data should see no effect.

Hour

year

DOY

Dec

2007

338

339

340

341

342

343

344

345

346

347

348

349

350

351

352